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Products => Test Equipment => Topic started by: TheSteve on February 12, 2016, 06:22:48 am

Title: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 12, 2016, 06:22:48 am
OK, perhaps it isn't really an SMU, its certainly not 4 quadrant, but its still darn cool for the price. The Agilent 66311B Mobile Communication DC Source supplies 0 - 15 volts at up to 3 amps and can sink 0-15 volts at up to 2 amps. It also has the expected CV and CC modes, OVP, OCP, output on/off and lots of other goodies including serial and GPIB interfaces. There is some very nice software for it that I don't even want to know the price of. It looks pretty unassuming but is 18 inches deep and weighs over 9 kilos(20 pounds). Programming accuracy is 0.05% + 10mV for voltage and 0.05% + 1.33 mA for current. DC measurement accuracy is 0.03% + 5mV - the current spec are pretty darn good as well. The data sheet on the whole series can be found here:
http://www.keysight.com/upload/cmc_upload/All/66300series_datasheet_Jan07.pdf (http://www.keysight.com/upload/cmc_upload/All/66300series_datasheet_Jan07.pdf)

I picked this unit off ebay for a best offer of 55 USD (and 35 for fedex ground shipping) in the usual "has errors, not working etc" state. When I received it I powered it up and it randomly gave me every error documented in the service manual. At first I thought maybe something was loose as errors are not generally that random. Then I had better look at it and noticed it said 220 VAC on the back. A read through a service note indicated they are all shipped for 220 VAC operation but can be jumpered to 120 VAC etc. Sure enough it was jumpered to 220 VAC. To configure it for 120 VAC it requires an extra jumper. Agilent was nice enough to provide the spare jumper - it is connected to unused lugs on the transformer. Once reconfigured it powered up without error and is working perfectly. The calibration looks great - everything checks out bang on with my new 34461A. The build quality looks very nice inside, Agilent didn't cheap out at all. It uses a connector on the back for power out and has sense lines to compensate for voltage drop. There is also a version with front mounted banana jacks - a quick look at the front panel shows the plastic is molded to accept two banana jacks so mine will likely get modified with a pair pretty quick. I'll jumper the sense line to the jacks which should be good enough for my use.

The seller has more of them, no idea if some have real faults or if they are all simply configured for 220 VAC.  I have NO connection to the seller, I just like what I got for 90 USD shipped.  # 281926297815 for those who want to try their luck - maybe someone can get them to accept an even lower best offer.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TiN on February 12, 2016, 06:28:56 am
That's some real transformer beef. How about more detailed PCB shots?
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 12, 2016, 06:48:45 am
That's some real transformer beef. How about more detailed PCB shots?

Absolutely!
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 12, 2016, 06:50:39 am
more pics
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 12, 2016, 06:51:42 am
And the transformer which has a total of 20 spade lugs coming out of it.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: crispy_tofu on February 12, 2016, 10:25:21 am
Wow, looks like a nice piece of kit!  :-+
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 12, 2016, 11:17:42 am
How if the fan noise of this thing? Is the fan always on or is it temperature controlled? HP/Agilent had a habit of not caring much about fan noise.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on February 12, 2016, 02:31:14 pm
I have some 66309D versions. I'd have to check the specs to see exactly how they differ from the 66311B. The 66309D is dual output, and the 66309D vs. the 66309B also has built-in DVM capability (with some limitations on range relative to the outputs).

The fan is always on, but it ramps up and down depending on the load. You definitely hear the fan even when not loaded.

They are surprisingly heavy for their size.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: PA0PBZ on February 12, 2016, 03:06:43 pm
The seller has more of them, no idea if some have real faults or if they are all simply configured for 220 VAC.  I have NO connection to the seller, I just like what I got for 90 USD shipped.  # 281926297815 for those who want to try their luck - maybe someone can get them to accept an even lower best offer.

The global shipping program alone takes $90 from me, so I'll pass this time.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 12, 2016, 03:30:12 pm
Now I'm tempted and I've got to have one if the price is right!  :P

edit: shippings costs are high indeed...
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: HighVoltage on February 12, 2016, 04:09:31 pm
The front and inside look very similar to the 6612C, just without the front binding post.
And the 6612C is much much more expensive.

Thanks for sharing the 66311B, I was not aware of this model.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: michaeliv on February 12, 2016, 04:49:10 pm
[...] and can sink 0-15 volts at up to 2 amps. It also has the expected CV and CC modes [...]
Manual says that it doesn't have CC sink capabilities. How does the sink feature actually work ? Does it actually display the real voltage when sinking ?
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on February 12, 2016, 06:56:22 pm
[...] and can sink 0-15 volts at up to 2 amps. It also has the expected CV and CC modes [...]
Manual says that it doesn't have CC sink capabilities. How does the sink feature actually work ? Does it actually display the real voltage when sinking ?

I just tried this with a 66309D with its output 1 connected to the output of a 6632B (0-20V, 0-5A). When the 6632B is programmed for a higher output voltage than the 66309D the 66309D will sink as much current as it is capable of doing while displaying the measured voltage at its output and the measured current that it is sinking. As long as the programmed current limit of the 6632B is within the current sinking capability of the 66309D the 6632B will be in CC mode and the voltage measured and displayed by both the 66309D the 6632B will be very close to the voltage programmed into the 66309D.

Figure 2-1. Dc Source Output 1 Characteristic in the manual shows the current sinking capability of approximately 2.8A at a programmed voltage of 0 volts dropping to a current sinking capability of approximately 1.2A at 15 volts. With the 66309D programmed for 0 volts I didn't see the UNR indicator turn on until the 6632B was set for closer to 3A, and when with the 66309D programmed for 15 volts I didn't see the UNR indicator turn on until the 6632B was set for closer to 1.6A. I didn't want to experiment too much with the 66309D current beyond the ranges specified in the manual.

In contrast the negative current sinking setting of the 6632B is programmable as the same setting as the positive current sourcing.

Agilent Part No. 5964-8125
USER’S GUIDE
Agilent Model 66111A
Fast Transient DC Source
Agilent Model 66311B/D, 66309B/D
Mobile Communications DC Source

Output 1 Characteristic

Figure 2-1 also shows a single range ? two quadrant capability. This means that the dc source is capable
of sourcing as well as sinking current over the output voltage range from zero volts to the rated voltage.
This negative current sinking capability provides fast downprogramming of the output of the dc source. It
can also be used to sink current from a battery charger, thus providing battery charger test capability. The
negative current is not programmable, and varies linearly from approximately 1.2 amperes at the full
rated voltage, to approximately 2.8 amperes at zero output voltage.

NOTE: If you attempt to operate the dc source beyond its output ratings, the output of the unit
may become unregulated. This is indicated by the UNR annunciator on the front panel.
The output may also become unregulated if the ac line voltage drops below the minimum
rating specified in Appendix A.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on February 12, 2016, 10:27:09 pm
Pulled the trigger on a $55 offer that was accepted. Thanks for the heads up!

Definitely want to do the front-panel binding posts mod, if my unit works. Anyone know of a good quality suitable type for this?
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 12, 2016, 10:35:58 pm
$55 seems to be the magic number the seller is looking for indeed. I bought one as well  :palm:
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ThomasDK on February 12, 2016, 10:51:50 pm
That's some real transformer beef. How about more detailed PCB shots?

Absolutely!
Interesting to see a DSP in a power supply. What was the original purpose of these supplies?

Thomas
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 12, 2016, 11:09:35 pm
Pulled the trigger on a $55 offer that was accepted. Thanks for the heads up!

Definitely want to do the front-panel binding posts mod, if my unit works. Anyone know of a good quality suitable type for this?

The Agilent variation uses a PCB but I am thinking the right posts will fit without too much effort. The holes are covered over only by the front label. I'll try to get some pics/measurements tonight or this weekend. The mounting portion of the post may need to be longer then normal because of how the plastic is molded.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 12, 2016, 11:12:05 pm
That's some real transformer beef. How about more detailed PCB shots?

Absolutely!
Interesting to see a DSP in a power supply. What was the original purpose of these supplies?

Thomas

They were intended to be used to characterize the power usage of mobile devices such as cellphones. There are variations of the supply that have dual outputs so you can power the phone with one supply and simulate the battery(charge and discharge) with the second supply.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Muxr on February 12, 2016, 11:33:27 pm
Hey, thanks for the tip. I picked one up as well. Will report once I get it.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 12, 2016, 11:37:09 pm
Another question: which type of plug is used for the output so I can order a replacement? I guess it will be missing...
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 12, 2016, 11:47:14 pm
The Agilent part # is 0360-2604
A google search indicates someone suggesting a Phoenix Contact 1757048 but that is not confirmed.
I see people also have them on ebay but they never seem to post the part # :)
I am using alligator clips at the moment.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 12, 2016, 11:55:41 pm
It looks like a standard Phoenix plug but it would be nice to know the exact pitch (5mm or 5.08mm).
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Muxr on February 13, 2016, 12:06:04 am
Man their website is pretty unintuitive. There is no easy way to get to the shopping cart. They have an easily accessible shopping quote cart. Clearly not optimized for the small fries shopping.

I was also going to pickup some DMM probes and they list the price with the Ask for Quote button, no buy button. They are probes..! I don't get it.

Anyways it's not letting me order, perhaps I need to wait to be approved.. I dunno. If you find a compatible plug let me know.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: GAD on February 13, 2016, 12:13:05 am
Offered $50 with the stipulation that it comes with all knobs and controls intact. He countered with $65, and I countered with $55, so yeah, it seems like $55 is the magic number. I've been curious about these for a while. Hell, more Agilent on the bench looks cool either way. :)

Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Muxr on February 13, 2016, 12:45:45 am
Well they declined my account creation because I used my gmail address. I found one on Ebay that oughta work though since my money is not good for them.

http://www.ebay.com/itm/252223006400 (http://www.ebay.com/itm/252223006400)
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 13, 2016, 12:51:28 am
I found one on Ebay that oughta work though since my money is not good for them.
http://www.ebay.com/itm/252223006400 (http://www.ebay.com/itm/252223006400)
$4.99 for that plug?  :wtf: Chances are it is a cheap Chinese knock-off you can by for $0.05. These pluggable terminal blocks are amongst the most cloned/copied parts!
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Muxr on February 13, 2016, 12:55:00 am
I found one on Ebay that oughta work though since my money is not good for them.
http://www.ebay.com/itm/252223006400 (http://www.ebay.com/itm/252223006400)
$4.99 for that plug?  :wtf: Chances are it is a cheap Chinese knock-off you can by for $0.05. These pluggable terminal blocks are amongst the most cloned/copied parts!
I was going to pay $17 to Keysight for it. With Chinese new years I would get the Chinese one in a month and a half. This is a bargain.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on February 13, 2016, 12:57:44 am
Offered $50 with the stipulation that it comes with all knobs and controls intact. He countered with $65, and I countered with $55, so yeah, it seems like $55 is the magic number. I've been curious about these for a while. Hell, more Agilent on the bench looks cool either way. :)
I guess that means I'll be getting one without a knob then!  :-DD
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Muxr on February 13, 2016, 12:58:57 am
Offered $50 with the stipulation that it comes with all knobs and controls intact. He countered with $65, and I countered with $55, so yeah, it seems like $55 is the magic number. I've been curious about these for a while. Hell, more Agilent on the bench looks cool either way. :)
I guess that means I'll be getting one without a knob then!  :-DD
If I get one without a knob I will 3D print us one. It may not be ideal but it'll work :P
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 13, 2016, 01:09:14 am
I'd use any knob I have around. No need to go through a lot of hassle. Besides that the rotating knob may not be very usefull. On my HP6572A it is easier to just use the keypad to enter the numbers than to endlessly rotate a knob.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 13, 2016, 01:16:59 am
I'd use any knob I have around. No need to go through a lot of hassle. Besides that the rotating knob may not be very usefull. On my HP6572A it is easier to just use the keypad to enter the numbers than to endlessly rotate a knob.

Indeed - the knob is nice to have but typing the value in is much quicker/easier.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on February 13, 2016, 01:18:03 am
The Agilent part # is 0360-2604
A google search indicates someone suggesting a Phoenix Contact 1757048 but that is not confirmed.
I see people also have them on ebay but they never seem to post the part # :)
I am using alligator clips at the moment.

Correct, Phoenix Contact  part number 1757048
MSTB 2.5
5 Position, 5.08 mm
$4.30 quantity one at Mouser
http://www.mouser.com/Search/ProductDetail.aspx?R=1757048 (http://www.mouser.com/Search/ProductDetail.aspx?R=1757048)

If you also want the standard sense jumpers for the output plug those are Phoenix Contact part number 1733169, $0.82 quantity one at Mouser.
http://www.mouser.com/Search/ProductDetail.aspx?R=1733169 (http://www.mouser.com/Search/ProductDetail.aspx?R=1733169)
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Muxr on February 13, 2016, 01:20:43 am
I'd use any knob I have around. No need to go through a lot of hassle. Besides that the rotating knob may not be very usefull. On my HP6572A it is easier to just use the keypad to enter the numbers than to endlessly rotate a knob.

Indeed - the knob is nice to have but typing the value in is much quicker/easier.
Yeah most of the time I would use the keyboard but sometimes you want the knob, for instance when you're working with LEDs or LCD displays, or analog circuits sensitive to varying voltages. This way you can observe the effect as you change the voltage by turning the knob.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on February 13, 2016, 01:29:30 am
The knob is Agilent / Keysight part number 33120-87401.

Cost you a whopping $3.11 if you can order one direct:

http://www.keysight.com/my/faces/partDetail.jspx?partNumber=33120-87401 (http://www.keysight.com/my/faces/partDetail.jspx?partNumber=33120-87401)
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on February 13, 2016, 01:59:43 am
I did some simple voltage programming accuracy tests with my 66309D supplies (same thing as a 66311B but with a second output channel and separate DVM input) and at least one of them was still pretty much spot on against the specifications for a 17 year old unit (serial number US3907xxxx), at least with zero output load.

I connected the 66309D output 1 to a 34401A (no idea when it was last calibrated, not since I acquired it quite a while ago) and swept the output voltage from 0 to the 15.535V maximum in 1 millivolt steps and compared the 66309D and 34401A measured voltages against each other and the programmed output voltage.

With a 12-bit DAC for programming the output voltage range that works out to be roughly 3.75mV programming resolution, and that is almost exactly what I was seeing, while the voltage read back from the 66309D was roughly within 1mV of the voltage read from the 34401A.


Title: Re: My poor mans SMU - The Agilent 66311B
Post by: bson on February 13, 2016, 02:41:08 am
Nice.  I have a 66312A (Dynamic Measurement Supply) I got for a good price although it has been used mainly as a spare extra supply so far.  The 66311B seems very similar despite its very different name; looks like they're very similar instruments in general.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ECEdesign on February 13, 2016, 03:41:23 am
Lucky day for the guy selling...  Seems like a cool device a regular power supply would work fine for me though.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 13, 2016, 04:51:10 am
Here is a picture from the inside showing where the binding posts will mount.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: mtdoc on February 13, 2016, 05:11:16 am
Damn you Steve and your eBay deals. You had to post this didn't you? I couldn't help myself and got one for $55 also... :P
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Scottjd on February 13, 2016, 11:43:14 am
Damn you Steve and your eBay deals. You had to post this didn't you? I couldn't help myself and got one for $55 also... :P
Well I don't know Steve or anything about his Ebay sales, but I decided to try my luck and make an offer.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Selectech on February 13, 2016, 02:54:36 pm
Decided to take a chance on this and got one last nite. Hope it's not too much fuss to get working, but for $55 worth a try.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Scottjd on February 13, 2016, 04:44:09 pm
Decided to take a chance on this and got one last nite. Hope it's not too much fuss to get working, but for $55 worth a try.
Well he counter offered, I woke up and saw the email but I guess they still sell during offers since the ad is closed. Oh well, wasn't meant to be.
So does Steve find these Ebay items like this a lot, maybe I should follow his posts. Is that even possible to follow a person on the EEVBlog?
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Scottjd on February 13, 2016, 04:53:27 pm
Decided to take a chance on this and got one last nite. Hope it's not too much fuss to get working, but for $55 worth a try.
Ah, you got the last one. Congrats..... Let me know how it goes or if I would have lost on it anyway. I still think it would have been a nice repair project even if it was more then a 220 to 110 jumper.
Do you mind if I ask how much you got it for?
It said three left when I made the offer. I think next time I shouldn't post until the offer is accepted, lol.  |O

I see he has two more, no knobs but I have a 3D printer. It's an easy print. But these specifically say does not power on so a little more risk in my mind since he still asking $99 for ones that don't power on, not just ones with errors. Repair cost in parts may be more then I can spend at this time if I need to order a power supply for the power supply.

If anyone else finds out the one they received is more then just the jumper and doesn't want to spend the time to troubleshoot further for repair please keep me in mind, I may take it off your hands. If it powers but with errors them I'm willing to fix the small parts.

Thanks,
Scott
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ECEdesign on February 13, 2016, 08:11:28 pm
New listing here might be able to haggle the price, this one is free shipping.  I can't picture what I would use this for so...

http://www.ebay.com/itm/HP-Agilent-66311B-Mobile-DC-Communications-Power-Supply-15V-3A-/151982820980?hash=item2362e1ce74:g:IuUAAOSwB4NWv4KR (http://www.ebay.com/itm/HP-Agilent-66311B-Mobile-DC-Communications-Power-Supply-15V-3A-/151982820980?hash=item2362e1ce74:g:IuUAAOSwB4NWv4KR)
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 19, 2016, 07:15:02 pm
Anyone got their unit yet? If yes: did it have a knob or not?
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: GAD on February 20, 2016, 12:14:57 am
I got mine today, and it's in rough shape, and did NOT come with a knob. Technically I believe I could return it because I specified my offer with a knob, but for the price I paid and the price of a knob I'm not sure I care. I'll take pics in a bit.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: GAD on February 20, 2016, 12:55:23 am
Opened it up with the service manual at the ready. It turns out that there is a spare jumper installed on the transformer! I pulled it, rearranged them accordingly, let it sit a bit, then fired it up and it works! The fan fired up, it self-tested, and is chugging along. The fan is noisy and needs to be replaced. This unit came not only without a knob, but also without a back bezel.

The only problem is that the VFD is so dim as to be practically unusable.


I was mildly amused because it's got 110V scribbled on top (It wasn't), and "powers on - takes 30 seconds" on the side (it didn't).

Pics:


(http://www.gad.net/GAD/Photos/TestEquipment/5D3_5724_1600.jpg)


(http://www.gad.net/GAD/Photos/TestEquipment/5D3_5725_1600.jpg)




(http://www.gad.net/GAD/Photos/TestEquipment/5D3_5730_1600.jpg)
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 20, 2016, 01:01:19 am
The spare jumper is cool - I mentioned it a while back. No rear bezel and a dim display doesn't really seem fair though. The dim display can perhaps be overlooked based on the listing but the unit should have been complete without missing hardware(other then the knob).

btw - when changing from 220 to 110 you're also supposed to install a 3.15 amp fuse. I installed a 3 amp fuse when I did the change.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on February 20, 2016, 01:24:31 am
Opened it up with the service manual at the ready. It turns out that there is a spare jumper installed on the transformer! I pulled it, rearranged them accordingly, let it sit a bit, then fired it up and it works! The fan fired up, it self-tested, and is chugging along. The fan is noisy and needs to be replaced. This unit came not only without a knob, but also without a back bezel.

According to the service manual the rear bezel part number may be 03478-88304. Listed as orderable for $19.01 if you can actually order one. I haven't ordered any Agilent/Keysight parts in quite a while. Not sure if I would bother replacing it myself. Maybe I would if I was also going to order a replacement front panel knob.

http://www.keysight.com/my/faces/partDetail.jspx?partNumber=03478-88304 (http://www.keysight.com/my/faces/partDetail.jspx?partNumber=03478-88304)
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: GAD on February 20, 2016, 01:25:55 am


Quote from: TheSteve on Today at 08:01:19 PM (https://www.eevblog.com/forum/index.php?topic=62908.msg873918#msg873918)
The spare jumper is cool - I mentioned it a while back. No rear bezel and a dim display doesn't really seem fair though. The dim display can perhaps be overlooked based on the listing but the unit should have been complete without missing hardware(other then the knob).

btw - when changing from 220 to 110 you're also supposed to install a 3.15 amp fuse. I installed a 3 amp fuse when I did the change.



Yeah, the fuse needs to be replaced. I misunderstood your post and thought that you asked Agilent for a jumper which they sent you for free. Rereading it now I see what you meant and must have completely spaced when I read it the first time.

The auction said "for parts or repair and is not working properly". It also did not show pics of the back. I doubt I'd win a dispute, and it was only $55 plus shipping, so I may just keep it and see if I can push the VFD back to brightness for a while or maybe just offer it up on eBay with an honest condition report and see what happens.

I was surprised at how heavy it is.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 20, 2016, 04:05:23 am
The fan is also loud, even when running properly. The fan speed is controlled by the current drain but they don't take into account the voltage out. I am sure not much heat is generated when it's outputting 15 volts @ 3 amps but they really rev that sucker up. Pretty sure mine will get a resistor mod at some point, or possibly even a different fan.

I did add the bottom feet and the front tilting legs as I found a new set I had ordered for a different project, gives it a great look on the bench,
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 20, 2016, 02:23:55 pm
So far I have modified all my HP power supplies with temperature controlled fans except for a 6572A which has a temperature controlled fan as standard. On the lower power ones (200W) my fan control board starts to turn the fan on when the heatsink gets to 30 deg. C and have the fan run at full speed when the heatsink is at 50 deg. C. In the higher power ones (1kW) the fan control board has the fan running at a low speed when the temperature is below 30 deg. C. On the 200W models the fan only runs slowly when the PSU is loaded to the max. On the 1kW models I don't remember the fans ever going faster than the default speed. All in all I think HP designed the fans so they provide enough cooling with the air vents clogged and the fan blades encrusted in a thick layer of dust!

If the 66311B is making lots of noise I think I'll add my standard fan control board to it.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Muxr on February 21, 2016, 01:07:56 am
Mine arrived a few days ago. No knob, but it had a sticker on it which said "working". I opened it up anyways. Looked good. Fired it up and it appears to be working. Can't really test it until my connector arrives in a few days.

The VFD is good on it, not dim. The fan is loud, will need modding.

(https://i.imgur.com/1WFqEkU.jpg)

In either case, very happy with the score, thanks TheSteve!
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 21, 2016, 01:17:19 am
Tell me how long it takes you to remove the "JRE0016" sticker. Mine came off with enough effort, but it was quicker to trouble-shoot and fix my voltage jumpers then to remove it. Unless of course you don't mind the stickers, then leave it.

I was pondering the difference between the 66311B and the 66321B last night. I can't help but wonder if they are identical hardware with just a firmware change. The service guide for the 66311B doesn't mention the 66321B that I can find. The 66321B has the same spec's but with "battery emulation". I have already used my 66311B in place of battery when testing some lithium chargers and it worked great as a load but the official feature would be nice. You can select the model # in the CAL/config menu but I don't want to risk losing my calibration as it is very good right now.

btw, mine has ROM A.02.04 and the CAL date is 09/08/06

edit - played around a little. First I dumped the config/cal eeprom (93C86) so I had a backup. I then went into the board init menu but my firmware only allows 66311B, 66311D, 66309B and 66309D to be selected. I was able to exit without losing any cal data. So there is no other model I can select that is useful.

Factory fan in mine is a 2410RL-04W-B60
When the 66311B powers on the default "low" speed runs the fan at 8.7 volts. It will ramp up as current goes up. I added a 30 ohm resistor in series with the fan and it still starts just fine and has calmed it down some. The best solution would probably be to buy a quiet fan.
I am currently running the unit limited to 2 amps into my 34461A DCI input to see if I can get any temp rise out of the exhaust air but so far feel very little  increase in temperature. Obviously sinking current will generate some heat but the fan should have no issues dealing with that.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on February 21, 2016, 02:10:45 pm

btw, mine has ROM A.02.04 and the CAL date is 09/08/06

edit - played around a little. First I dumped the config/cal eeprom (93C86) so I had a backup. I then went into the board init menu but my firmware only allows 66311B, 66311D, 66309B and 66309D to be selected. I was able to exit without losing any cal data. So there is no other model I can select that is useful.


Do you have the means to read and dump the ROM A.02.04 firmware? I think it's in either a 28- or 32-pin PLCC package.

I think I have either A.02.01 or A.02.02 in my 66309D supplies and there are some additional settings available in the A.02.04 firmware. (For example whether the dual supplies switch on/off together or independently). I don't know for sure the firmware is actually the same between the 66311B, 66311D, 66309B and 66309D models.

How did you dump the config/cal eeprom (93C86)?
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: GAD on February 21, 2016, 06:22:43 pm
Mine arrived a few days ago. No knob, but it had a sticker on it which said "working". I opened it up anyways. Looked good. Fired it up and it appears to be working. Can't really test it until my connector arrives in a few days.

The VFD is good on it, not dim. The fan is loud, will need modding.

(https://i.imgur.com/1WFqEkU.jpg)

In either case, very happy with the score, thanks TheSteve!

Yours looks positively new compared to mine. Anyone else receive one that looks as bad as mine?
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 21, 2016, 06:49:49 pm

btw, mine has ROM A.02.04 and the CAL date is 09/08/06

edit - played around a little. First I dumped the config/cal eeprom (93C86) so I had a backup. I then went into the board init menu but my firmware only allows 66311B, 66311D, 66309B and 66309D to be selected. I was able to exit without losing any cal data. So there is no other model I can select that is useful.


Do you have the means to read and dump the ROM A.02.04 firmware? I think it's in either a 28- or 32-pin PLCC package.

I think I have either A.02.01 or A.02.02 in my 66309D supplies and there are some additional settings available in the A.02.04 firmware. (For example whether the dual supplies switch on/off together or independently). I don't know for sure the firmware is actually the same between the 66311B, 66311D, 66309B and 66309D models.

How did you dump the config/cal eeprom (93C86)?

The firmware should be compatible with your model. Have you checked to see what part number the ROM is? If it's compatible with a programmer/socket I have I can dump it. I read the eeprom in circuit with a UPA-USB programmer using an SOIC clip. I don't think I'd program it in circuit though unless the processor was held in reset.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: mtdoc on February 21, 2016, 08:43:22 pm

Yours looks positively new compared to mine. Anyone else receive one that looks as bad as mine?

Mine is due to arrive on Tuesday. I'll let you know.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on February 21, 2016, 09:33:00 pm
The firmware should be compatible with your model. Have you checked to see what part number the ROM is? If it's compatible with a programmer/socket I have I can dump it. I read the eeprom in circuit with a UPA-USB programmer using an SOIC clip. I don't think I'd program it in circuit though unless the processor was held in reset.

The A2 board block diagram in the service manual shows it as a 4Mbit 256Kx16 part and it is an AMD part in a 44-pin PLCC package so that should make it an Am27C4096 on the 5064-0088 version of the A2 board in my 66309D. I haven't gone back to peel off the firmware version part number sticker on the OTP EPROM yet to verify that is the actual part number.

-Glen
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 21, 2016, 11:06:58 pm
The firmware should be compatible with your model. Have you checked to see what part number the ROM is? If it's compatible with a programmer/socket I have I can dump it. I read the eeprom in circuit with a UPA-USB programmer using an SOIC clip. I don't think I'd program it in circuit though unless the processor was held in reset.

The A2 board block diagram in the service manual shows it as a 4Mbit 256Kx16 part and it is an AMD part in a 44-pin PLCC package so that should make it an Am27C4096 on the 5064-0088 version of the A2 board in my 66309D. I haven't gone back to peel off the firmware version part number sticker on the OTP EPROM yet to verify that is the actual part number.



-Glen

Well I'm happy to give it a go if you can get me an actual part #.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on February 21, 2016, 11:26:50 pm
The firmware should be compatible with your model. Have you checked to see what part number the ROM is? If it's compatible with a programmer/socket I have I can dump it. I read the eeprom in circuit with a UPA-USB programmer using an SOIC clip. I don't think I'd program it in circuit though unless the processor was held in reset.

The A2 board block diagram in the service manual shows it as a 4Mbit 256Kx16 part and it is an AMD part in a 44-pin PLCC package so that should make it an Am27C4096 on the 5064-0088 version of the A2 board in my 66309D. I haven't gone back to peel off the firmware version part number sticker on the OTP EPROM yet to verify that is the actual part number.



-Glen

Well I'm happy to give it a go if you can get me an actual part #.

I double checked and I was not correct the first time. The A.02.02 firmware I have in my 66309D is actually in an AMD Am27C2048-120JC part. That is a 2Mbit (131,072 x 16) OTP EPROM in a 44-pin PLCC package.  Manufacturer Code 01H, Device Code 98H.

Version A.02.02 firmware binary dumped from my 66309D attached in the .ZIP file here.

Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 22, 2016, 12:13:57 am
I should be able to dump 02.04 shortly. I have a DIP40 to PLCC44 adapter that I got with my TL866CS programmer however the pin conversion is not quite correct for a 27C2048. The NC pins are connected where Vss needs to be.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Muxr on February 22, 2016, 12:24:25 am
Mine arrived a few days ago. No knob, but it had a sticker on it which said "working". I opened it up anyways. Looked good. Fired it up and it appears to be working. Can't really test it until my connector arrives in a few days.

The VFD is good on it, not dim. The fan is loud, will need modding.

(https://i.imgur.com/1WFqEkU.jpg)

In either case, very happy with the score, thanks TheSteve!

Yours looks positively new compared to mine. Anyone else receive one that looks as bad as mine?
Your image may make it a bit worse than it really is, because you got a lot of lighting in that picture. Mine looks much better than my Keithley 2015 which needs a new VFD, and it doesn't look very warn but my image is also in relative dark (btw I prefer working in the dark with just spotlights, can't stand glare on the screens)
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 22, 2016, 12:48:10 am
This is firmware version A.02.04 as dumped from my 66311B. In the init menu it lets me choose 63311B, 63311D, 66309B or 66309D so those models should be supported by it.

For anyone wanting to dump it with a TL866CS/TL866A programmer two jumpers need to be added to the DIP40 to PLCC44 adapter board to connect the Vss pins. I jumpered PLCC pins 12 to 13 and 33 to 34 on the adapter board. My 66311B uses an Atmel AT27C2048 with chip ID 001E 00F7.

As far condition of my unit the front has some small dents and marks. I removed several stickers from the front as well. The back plastic bezel is cracked but holds together and the chassis itself has had paint scraped off in a few places. I am thinking my VFD is probably 75% as bright as when new.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on February 22, 2016, 01:16:03 am
Cool, thanks for taking the time to dump the A.02.04 firmware.  AMD Am27C2048 parts are no longer available new but Mouser has the Atmel AT27C2048 in stock for around $4 each. I'll have to pick up some blank parts and give the A.02.04 firmware a try.

I do see the COUPLE:OUTPUT string in the A.02.04 firmware binary which isn't present in the A.02.02 firmware binary. That is consistent with the User's Guide part number 5964-8125. Of course that doesn't make any difference in the single output 66311B/D models.

Also I noticed "PEEK" and "POKE" strings in the firmware binary. I wonder if those could be used to read and write the cal/config 93C86 EEPROM? I'll have to try to experiment with that.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 22, 2016, 01:27:48 am
Cool, thanks for taking the time to dump the A.02.04 firmware.  AMD Am27C2048 parts are no longer available new but Mouser has the Atmel AT27C2048 in stock for around $4 each. I'll have to pick up some blank parts and give the A.02.04 firmware a try.

I do see the COUPLE:OUTPUT string in the A.02.04 firmware binary which isn't present in the A.02.02 firmware binary. That is consistent with the User's Guide part number 5964-8125. Of course that doesn't make any difference in the single output 66311B/D models.

Also I noticed "PEEK" and "POKE" strings in the firmware binary. I wonder if those could be used to read and write the cal/config 93C86 EEPROM? I'll have to try to experiment with that.

I haven't tried it but the 53131A/53132A series of frequency counters lets you read/write the calibration data via GPIB, you could always give that a shot via GPIB or the serial port for fun.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on February 22, 2016, 02:32:04 am
FWIW, it appears that the commands "DIAG:PEEK? #H0000" through "DIAG:PEEK? #HFFFF" will dump the 256KB firmware 4 bytes at a time.

If the config/cal EEPROM is also mapped somewhere in the DIAG:PEEK address space it would take some time to try to figure that out.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on February 22, 2016, 11:21:45 pm
As a simple exercise in PyVISA programming I wrote a simple script to read the firmware from a 66309D through the GPIB interface and dump it to a binary file. It took about 22 minutes to run to completion using an E2050A GPIB/LAN gateway to interface to the 66309D. I verified that the firmware binary file dumped using this method exactly matched the A.02.02 binary file produced by dumping the Am27C2048 EPROM using a device programmer.

I'm a complete novice at Python programming and I'm sure there are better and more elegant ways to implement this, but it did the job...
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 22, 2016, 11:24:31 pm
Very cool! Perhaps someone will receive a unit with newer firmware and can dump it for the rest of us without even opening it up.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 23, 2016, 08:05:06 pm
I have received my 66311B today together with the feet I ordered from Malaysia. Mine has a knob and rear bezel so at least it is complete. After setting it to 230V it worked right away. It seems my one is controlling the fan speed based on the amount of current drawn from it. My 66311B is missing the name plate and the plastic covering the display was dull (which made the VFD hard to read). I polished it back to being shiny using a strong polish for use on a car.

The unit is very heavy indeed. Not so much because of the transformer but due to the steel casing and inner frame. I wish Agilent/Keysight kept using the light weight aluminium chassis and casings.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 23, 2016, 08:24:25 pm
I believe they all control fan speed based on current sourced or sinked - in my case it was loud even at the minimum setting which starts at about 8.7 volts.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: mtdoc on February 23, 2016, 10:07:00 pm
Mine arrived today and it looks like I lucked out and got one with a knob and a bright display.  :)
(https://www.eevblog.com/forum/testgear/my-poor-mans-smu-the-agilent-66311b/?action=dlattach;attach=203445;image)
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 23, 2016, 11:26:40 pm
I checked mine against a Keysight 34461A and it seemed to be 10mV off. One of the reasons is that the setting accuracy isn't that good (a few mV per step). I performed the voltage calibration procedure and that made sure the reading on the 66311B matches the 34461A.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: mtdoc on February 24, 2016, 03:40:30 am
Well, I've fired mine up and played around with it a bit. Yes, the fan is loud!.  I think I will replace it with one of these  (http://www.newegg.com/Product/Product.aspx?Item=N82E16811999615&cm_re=vantec_thermoflow-_-11-999-615-_-Product) Vantec temp controlled fans.  I did that with my HP 6632A and it worked well. It might be a risk if it was being pushed to its power limits for extended periods but I'm not likely to do that.

Also, I think front binding posts are in order. I see the cutouts are there but no easy access output pads next to them as there is in the HP 6632A.

Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Selectech on February 24, 2016, 03:51:24 am
My unit arrived today. No knob, but blue tape on the side said it was working -- and it is working. Bright, even display, checked some current & voltage settings. Control buttons all work ok.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: mtdoc on February 24, 2016, 03:58:57 am
My unit arrived today. No knob, but blue tape on the side said it was working -- and it is working. Bright, even display, checked some current & voltage settings. Control buttons all work ok.

Yeah, mine had one of the pieces of blue tape as well.  Worked right away - no jumper change to 120V needed.
I haven't had a chance to check the accuracy yet.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: stuartk on February 25, 2016, 02:56:28 am
I received mine also today. Display at 80% brightness, no knob but otherwise cosmetically OK. Minor scuffing of the display.

It had a blue sticker on it that said working and it worked out of the box fine. The fan is noisy though.

I think I'm going to call Keysight for a set of feet and a knob.

Any suggestions for where to get a new 2410ML-04W  fan? They seem pretty pricey.

Anyone have leads on binding posts that fit into the front of the unit?

Stuart
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: macboy on February 25, 2016, 02:18:07 pm
...I think I'm going to call Keysight for a set of feet and a knob.
...
Anyone have leads on binding posts that fit into the front of the unit?

Stuart
Maybe people here would be interested in a group buy for the knob and possibly feet. That would avoid minimum order issues and probably reduce shipping costs (even after mailing out to individuals).

As for the front panel holes, those are for BNC plugs such as used with the 33120A arb generator:
(http://www.atecorp.com/ATECorp/media/ProductImages/33120A-Agilent-SignalGenerators.jpg)
As you can see, the layout of the front panel including buttons is identical. I'm not saying you won't find binding posts that fit, but I don't think they were designed for them.

Mine arrived yesterday, through the Global shipping program. It was in rough condition. The PCB of the display board was dislodged, so the buttons were all recessed and impossible to push. The display lens was very scuffed, almost like someone cleaned it with fine sandpaper, there was a large 8"x10" patch of sticker residue on the top. And the inside is completely caked with brown dust. You can't see anything through it. Just brown PCBs. Yuck. I dismantled the front panel and cleaned the switch membrane and plastics with soap and water. I removed and polished the lens the best I could (not bad). A citrus cleaner removed the giant patch of sticker residue, then IPA removed the citrus oil. I removed some dust but the rest will have to wait, that is a big job. The VFD is showing some age with slightly dimmed segments, but overall it is fine. No knob. It is HP branded, not Agilent like mtdoc's lucky score. Mine was labelled as working and it is. The output is within 0.1%. Mine did not come with the output connector, but did have the INH/FLT connector, which I re-purposed to the output (it is only 4 position, so no ground connection).
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 25, 2016, 02:44:23 pm
I have attached some 2.5mm^2 silicone leads with 4mm banana sockets to the rear plug. Front posts would be nice but to do it right you'd also want the sense connections on the front. Perhaps even a switch to select between local and remote sensing. The current is quite low to small posts would be sufficient.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: stuartk on February 25, 2016, 03:59:55 pm
I have an SMD unit manufactured in 2003. Some of the older ones are through hole construction. Much of the PCB is un-populated, presumably for better models.

I opened mine up and cleared out a small spider web near the fan and dust over the fan and heat sink. I blew some crap out of it, fan is less noisy now.

I reconfigured the transformer lugs for 120 VAC operation.

There are only 2 post spots on the front panel, so to run both output and sense it would require 2 female BNC connectors as macboy is suggesting, instead of banana posts which would only give output.

I took a cursory look at the power PCB without removing the top and I didn't see any place to connect the outputs. It would require removing the PCB and soldering to the bottom of it.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: SKPang on February 25, 2016, 04:52:59 pm
Mine arrived today but it was in pretty bad shape. The plastic at the rear was bent, no knob and sticky power switch.

Cleaned the unit up and fixed the sticky power switch. Changed the input voltage to 230V and power it up.

It works fine, the fan is a bit noisy. Can't really complain much for $55. Nice addition to the lab gear.

Now time to get a new knob.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on February 25, 2016, 06:37:04 pm
Maybe people here would be interested in a group buy for the knob and possibly feet. That would avoid minimum order issues and probably reduce shipping costs (even after mailing out to individuals).
I would likely be interested, but mine hasn't arrived yet, so will have to see what kind of shape it's in...

Canada Post's tracker says it should arrive tomorrow, but they are often a day optimistic.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: bson on February 26, 2016, 08:34:35 am
The 66312 has front panel outputs (though the sense inputs are in the rear) and it should be a simple matter to install a pair of binding posts.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on February 26, 2016, 09:42:40 am
Went looking for the 66312 binding posts part numbers and figured I'd grab some others from the 66311 in case of a potential group buy or general interest for those wanting replacement parts. The binding posts are a tad on the pricey side... but I figured the information might be useful anyway. Prices in CAD.

Binding Post - 1510-0091 - $29.02
Binding Post - 1510-0090 - $15.39 - Half price, this one looks identical but isn't red or listed on the BOM

The binding posts seem to be mounted on a PCB with a couple low-value capacitors and a 1R resistor. It's not clear if the PCB is for structure or if the posts mount solidly to the chassis themselves. The PCB is available as part number 06611-60022 for $72.54.

Other useful parts, given the condition of people's units:

Fan Assy - 5065-7092 - $155 (hahahaha right)
Knob - 33120-87401 - $3.67
Rear Bezel - 03478-88304 - $22.45
Foot (x4) - 5041-8801 - $19.00
5 position terminal block (output) - 0360-2604 - $19.00 (or get two from Mouser for less, incl. shipping...)
Front window - 5080-2617 - $10.19

I'm surprised at the reasonable pricing, TBH. Not sure how painful it is to order, I think there is an automated process in the US, but in Canada it seems I need to call them...
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: stuartk on February 26, 2016, 03:10:02 pm
The software looks really interesting and would make this meter more useful:

http://www.keysight.com/en/pd-852417-pn-14565B/device-characterization-software-with-test-automation?nid=-536902309.389074.00&cc=CA&lc=eng (http://www.keysight.com/en/pd-852417-pn-14565B/device-characterization-software-with-test-automation?nid=-536902309.389074.00&cc=CA&lc=eng)

However at $2,779 CDN I'd have to be smoking crack to buy it.....  |O
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: SKPang on February 26, 2016, 03:55:08 pm
Got my terminal block today from Farnell / element 14.

5way 5.08mm Phoenix contact. Order code : 3705389 £2.69 + VAT
4way 5.08mm Phoenix contact. Order code : 3705377 £2.18 + VAT

There are some cheaper make but I like to stick with Phoenix.

Title: Re: My poor mans SMU - The Agilent 66311B
Post by: mtdoc on February 26, 2016, 05:29:46 pm
Not sure how painful it is to order, I think there is an automated process in the US, but in Canada it seems I need to call them...

To order online in the U.S. requires a valid business email domain and valid matching business address for shipping and billing. I tried once using my work email and home address for billing and they rejected it. Maybe I could have called to make it happen but it wasn't worth the effort. I'm not sure how they benefit from making it so restrictive.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on February 26, 2016, 08:58:56 pm
My unit has arrived. Looks like similar condition to others - missing rear bezel and knob, fairly dirty, and the front window is pretty badly scratched, though doesn't hamper use. There is a toggle switch on the rear marked AC-I CAL that also seems to be physically broken (the toggle just floats around). Shows -50mA with no load so probably needs calibration.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 26, 2016, 09:06:04 pm
Sounds like an interesting user added mod that needs to be removed.

I will be doing a Keysight parts order soon if you need a knob ve7xen - however I'm in Langley and with the cost of fuel/tolls it probably wouldn't be worth your time.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on February 26, 2016, 09:32:04 pm
Sounds like an interesting user added mod that needs to be removed.
It certainly doesn't look user-added, as the label seems to be printed on the same sticker as all the other rear-panel markings (see attached). I can't find any reference to it in the service or user manuals, or the current product info though. The closest thing I found was the inhibit calibration switch (I CAL), but the AC bit is confusing. Most likely this is what it is though, as it says 'hold to cal'. I wonder if this is a discontinued orderable option? My unit is HP marked so it must be fairly old.

Quote
I will be doing a Keysight parts order soon if you need a knob ve7xen - however I'm in Langley and with the cost of fuel/tolls it probably wouldn't be worth your time.
I might take you up on that if you don't mind just mailing a couple items to me by post. I'll PM you.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 26, 2016, 09:52:11 pm
Yep, that has got to be a factory option. I see you also have the local/remote sense switch. I am guessing your board is through-hole instead of surface mount.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: stuartk on February 26, 2016, 09:56:13 pm
I'm not sure when they switched from through hole to surface mount. Look at the first 2 digits of your serial number and add 1960. This gives you the year of manufacture. The next 2 digits are the week.

My first 4 digits are 4300, meaning manufactured in 2003, week 0
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on February 26, 2016, 10:02:15 pm
Mine is 1998/44.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: bson on February 27, 2016, 02:34:53 am
Not sure how painful it is to order, I think there is an automated process in the US, but in Canada it seems I need to call them...
They're a complete pain in the arse in the U.S. - you have to get a quote for the $3.67 knob, then because they don't have a checkout system you have to either telephone or telefax (yeah, right, remember those things?) payment information like a credit card.  The net result it takes someone there 15-20 min to take your order, spell out your shipping address, etc 7 times to make sure there are no errors, for a sub $5 sale.  They waste both their own and your time, either of which amounts to a lot more than than the price of a plastic knob.  They're just not in the modern epoch.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on February 28, 2016, 05:58:23 am
So I've done some additional testing/calibration, and my box does great as a power supply, well within spec per the verification procedure after calibration. However the current sink seems to have failed short. Though this would seem to short across the output rails, so perhaps it is part of the control circuitry for the 'downprogrammer' that's the problem.

In trying to track this down I'm finding this is by far the worst piece of HP test equipment to work on I've ever seen. All the component designators are hidden under the components, many of the test points called out in the service manual are unreachable with normal probes, and no schematic or component placement diagram seems to be available. It looks like I'm going to have to remove the A1 board to do further testing, which is also a much more arduous chore than most HP gear.

Ah well, at least it makes a great power supply if nothing else.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 28, 2016, 03:13:29 pm
For who still wants one: it seems the seller has another 18 pieces for sale
http://www.ebay.com/itm/HP-Agilent-Keysight-66311B-Mobile-Communications-DC-Source-/272149540406 (http://www.ebay.com/itm/HP-Agilent-Keysight-66311B-Mobile-Communications-DC-Source-/272149540406)
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: macboy on February 28, 2016, 08:18:03 pm
So I've done some additional testing/calibration, and my box does great as a power supply, well within spec per the verification procedure after calibration. However the current sink seems to have failed short. Though this would seem to short across the output rails, so perhaps it is part of the control circuitry for the 'downprogrammer' that's the problem.

In trying to track this down I'm finding this is by far the worst piece of HP test equipment to work on I've ever seen. All the component designators are hidden under the components, many of the test points called out in the service manual are unreachable with normal probes, and no schematic or component placement diagram seems to be available. It looks like I'm going to have to remove the A1 board to do further testing, which is also a much more arduous chore than most HP gear.

Ah well, at least it makes a great power supply if nothing else.
Keep in mind that while it can sink current, it is not programmable. The current sink will be around 1 to 2.5 A (depending on voltage at output terminals), regardless of programmed current limit.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: amc184 on February 29, 2016, 05:14:26 am
Quote
Keep in mind that while it can sink current, it is not programmable. The current sink will be around 1 to 2.5 A (depending on voltage at output terminals), regardless of programmed current limit.

Damn, that's pretty disappointing.

I've been following this thread after I bought a similar instrument from Keithley, the 2304A.  The 2304A's current sinking is programmable, you can set it for, say, 0V, 10mA, and it will act as a 10mA load (max sink is 3A).  They're such similar devices that I'd assumed they had the same features.  Those who are after a low power, high accuracy programmable load (a don't mind a rubbish user interface), keep the 2304A in mind, they sometimes go cheap.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on February 29, 2016, 07:24:16 am
Quote
Keep in mind that while it can sink current, it is not programmable. The current sink will be around 1 to 2.5 A (depending on voltage at output terminals), regardless of programmed current limit.

Damn, that's pretty disappointing.

I've been following this thread after I bought a similar instrument from Keithley, the 2304A.  The 2304A's current sinking is programmable, you can set it for, say, 0V, 10mA, and it will act as a 10mA load (max sink is 3A).  They're such similar devices that I'd assumed they had the same features.  Those who are after a low power, high accuracy programmable load (a don't mind a rubbish user interface), keep the 2304A in mind, they sometimes go cheap.

There are other HP/Agilent supplies which are programmable for the current sink level. For example the 6632B which is 20V / 5A, where the current sink level isn't separately programmable from the current source level, the sink level matches the programmed source level. Yes it's too bad the 66309/66311 do not also have that feature.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: stuartk on February 29, 2016, 02:58:28 pm
So it seems that Keysight Canada has a minimum $50 order.   :(
I'm not certain what shipping is

The parts I need are:

Feet: 5041-8801 $19 CAD (I'm assuming that it contains 4 feet, not 1 foot although you never know) The fellow at Keysight told me he didn't know if it was 1 foot or 4 feet as the parts don't show up on their system. He said it's an Agilent product and referred me to Agilent who said that it's a Keysight device and part and they don't sell parts.... |O

Knob:33120-87401 $3.67

Is anyone coordinating a group buy to get over the minimum?

I'm certainly happy to pay for a share of the order + shipping + handling + pain and suffering

Stuart
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on February 29, 2016, 03:02:21 pm
Feet can be bought from Ebay for less money then Keysight is asking. Isn't there some generic knob which will fit?
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: SKPang on February 29, 2016, 03:37:00 pm
I've ordered the knob from Keysight UK. £2.16 + VAT with free delivery.

Paid by credit card and thats it. No minimum order. Should be here this week.

Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on February 29, 2016, 04:31:45 pm
So I've done some additional testing/calibration, and my box does great as a power supply, well within spec per the verification procedure after calibration. However the current sink seems to have failed short. Though this would seem to short across the output rails, so perhaps it is part of the control circuitry for the 'downprogrammer' that's the problem.

In trying to track this down I'm finding this is by far the worst piece of HP test equipment to work on I've ever seen. All the component designators are hidden under the components, many of the test points called out in the service manual are unreachable with normal probes, and no schematic or component placement diagram seems to be available. It looks like I'm going to have to remove the A1 board to do further testing, which is also a much more arduous chore than most HP gear.

Ah well, at least it makes a great power supply if nothing else.
Keep in mind that while it can sink current, it is not programmable. The current sink will be around 1 to 2.5 A (depending on voltage at output terminals), regardless of programmed current limit.

Thanks I will look into this when I return home next week. From my reading of the verification procedure it seemed that it was programmable, and the block diagram does seem to show a constant current loop around the downprogramming regulator, so I'm not so sure that's the case, but you're probably right. I was seeing the 66311B put my 3.5A power supply into CC mode at 3.5A, while the display on the 66311B would show the setpoint on the current readback, which seemed a bit weird to me.

@stuartk Not willing to coordinate, but if you are I'm in for a couple of items ;).
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: macboy on February 29, 2016, 05:23:49 pm
So I've done some additional testing/calibration, and my box does great as a power supply, well within spec per the verification procedure after calibration. However the current sink seems to have failed short. Though this would seem to short across the output rails, so perhaps it is part of the control circuitry for the 'downprogrammer' that's the problem.

In trying to track this down I'm finding this is by far the worst piece of HP test equipment to work on I've ever seen. All the component designators are hidden under the components, many of the test points called out in the service manual are unreachable with normal probes, and no schematic or component placement diagram seems to be available. It looks like I'm going to have to remove the A1 board to do further testing, which is also a much more arduous chore than most HP gear.

Ah well, at least it makes a great power supply if nothing else.
Keep in mind that while it can sink current, it is not programmable. The current sink will be around 1 to 2.5 A (depending on voltage at output terminals), regardless of programmed current limit.

Thanks I will look into this when I return home next week. From my reading of the verification procedure it seemed that it was programmable, and the block diagram does seem to show a constant current loop around the downprogramming regulator, so I'm not so sure that's the case, but you're probably right. I was seeing the 66311B put my 3.5A power supply into CC mode at 3.5A, while the display on the 66311B would show the setpoint on the current readback, which seemed a bit weird to me.
...
I'm looking at the user manual, "USER’S GUIDE Agilent Model 66111A Fast Transient DC Source Agilent Model 66311B/D, 66309B/D Mobile Communications DC Source", Agilent Part No. 5964-8125, Page 144 "Supplemental Characteristics". The note given for the sink current states:
Quote
1 The sink current decreases linearly from 2.8A @ 0 V to 1.2 A @ 15 V. Sink current does not track the programmed current.
Also on page 26,
Quote
Figure 2-1 also shows a single range ? two quadrant capability. This means that the dc source is capable
of sourcing as well as sinking current over the output voltage range from zero volts to the rated voltage.
This negative current sinking capability provides fast downprogramming of the output of the dc source. It
can also be used to sink current from a battery charger, thus providing battery charger test capability. The
negative current is not programmable, and varies linearly from approximately 1.2 amperes at the full
rated voltage, to approximately 2.8 amperes at zero output voltage.".
This really is too bad.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: mtdoc on February 29, 2016, 06:40:52 pm
It is too bad about the lack of programmable current sinking.

Yesterday I replaced the loud fan with a quiet Vantec temp controlled fan. Much better!

I also ordered the Phoenix connector from Digikey. I think I'll hold off on front terminals.

I noticed NI makes a driver for this unit.  I wonder if anyone has developed a LabView VI for this?  The Keysight software looks nice but just way too expensive.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on February 29, 2016, 06:45:02 pm
So it seems that Keysight Canada has a minimum $50 order.   :(
I'm not certain what shipping is

The parts I need are:

Feet: 5041-8801 $19 CAD (I'm assuming that it contains 4 feet, not 1 foot although you never know) The fellow at Keysight told me he didn't know if it was 1 foot or 4 feet as the parts don't show up on their system. He said it's an Agilent product and referred me to Agilent who said that it's a Keysight device and part and they don't sell parts.... |O

Knob:33120-87401 $3.67

Is anyone coordinating a group buy to get over the minimum?

I'm certainly happy to pay for a share of the order + shipping + handling + pain and suffering

Stuart

Once you hit 50 dollars the shipping is free from Keysight Canada.
This is the foot package I bought for something else but ended up using with the 66311B - check out ebay # 151996686789
The metal flip out legs work very nicely, and you need the locking tabs.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: stuartk on February 29, 2016, 08:08:18 pm
Quote
Yesterday I replaced the loud fan with a quiet Vantec temp controlled fan. Much better!

Out of curiosity, what do you do with the 3rd wire (yellow) on the Vantec fan?
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: mtdoc on February 29, 2016, 08:14:36 pm
Quote
Yesterday I replaced the loud fan with a quiet Vantec temp controlled fan. Much better!

Out of curiosity, what do you do with the 3rd wire (yellow) on the Vantec fan?

Coiled it and zip tied it out of the way. Could also be cut off but just in case I re-purpose the fan at some point.  The yellow wire is for RPM detection on a computer motherboard I believe. It is not involved in the temp control.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: samofab on March 02, 2016, 09:03:30 pm
Mine arrived today. It was described as "doesn't power on". Two fuses later (one soldered) and some TLC and it works as new. Sometime in its history it fell hard on the front panel. Miraculously, there was no permanent damage. Only transformer retaining sheet metal was slightly bent.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: SKPang on March 03, 2016, 01:51:58 pm
The knob has arrived. They shipped it in a massive box.

The unit looks a bit nicer now.  :)

Title: Re: My poor mans SMU - The Agilent 66311B
Post by: gslick on March 03, 2016, 04:55:22 pm
The knob has arrived. They shipped it in a massive box.

The unit looks a bit nicer now.  :)

You only paid £2.16 + VAT with free delivery for the knob in an antistatic bag in that huge box? How much did they lose on that transaction?  :)
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: SKPang on March 03, 2016, 05:01:19 pm
Yes, a total of £2.59 I think the shipping cost is more then that.

Title: Re: My poor mans SMU - The Agilent 66311B
Post by: Muxr on March 03, 2016, 05:11:40 pm
I am going to have to 3D print mine since Agilent won't sell me one.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: MountainEEV on March 04, 2016, 03:14:25 am
Mine just arrived today and appears to be intact.  Powers on without errors but fan is not spinning at all. :--  I have done limited testing so far as I'm waiting for phoenix connectors to arrive.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on March 04, 2016, 10:39:31 pm
The 0.05% accuracy spec seems to be driven by the limited voltage setting resolution and probably also the large output current but I wanted to know how stable it is over a longer time period like one hour with a very light load attached. I took two measurements. The first one is at 5V where the measurement is started after the 66311B has been on for 15 minutes, the second measurement is at 500mV and includes the 66311B heating up. The measurement is taken with a 2200uf capacitor across the DVM inputs.

At 5V the variation is less than 165uV:
(https://www.eevblog.com/forum/testgear/my-poor-mans-smu-the-agilent-66311b/?action=dlattach;attach=206016;image)

At 500mV the variation is less than 125uV:
(https://www.eevblog.com/forum/testgear/my-poor-mans-smu-the-agilent-66311b/?action=dlattach;attach=206018;image)

At least the drift doesn't get significantly better or worse with higher or lower output settings. Still I wonder if the temperature drift could be improved by putting a small heater on top of the voltage reference in the 66311B or that the drift is mainly due to temperature dependant offset voltage drift in other components.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on March 05, 2016, 12:08:13 am
Looks like I have an 66319D coming. It has dual outputs and the volt meter option. It can also do battery emulation. Should be fun to compare it to the 66311B to see what the differences are. I will also post the firmware.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on March 06, 2016, 12:53:22 am
So a lesson in getting too overzealous with repairs...

Today I decided to poke around the front panel board and try and get a bit more brightness out of my VFD by running the filaments hot for a few minutes. While probing around looking for the filament supply, I accidentally shorted the last two pins in one of the groups on the VFD - something at +12V and a driver output or micro pin or something. Killed the whole front panel, just junk on the display.

Of course I couldn't put it down and think clearly or be patient, so i attempted to use a heat gun to desolder the VFD and inspect the circuits on the other side, with the intent of replacing whatever part I'd fed 12V up the backside of. Of course the heat gun is not the correct tool for the job, and I now have a ruined FFC connector and several random parts unintentionally desoldered - but the VFD remains.

If anyone has a picture of the top side of the front panel PCB, without the VFD installed, or a schematic, or even a BOM with part designators, that would be extremely helpful. I don't think there is component level information available on this box, but maybe there are other models using the same front panel? Also knowing what 8-pin FFC connector would work would be nice, though there is an unused one on the mainboard I can steal.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: stuartk on March 06, 2016, 01:50:01 am
I know how you feel. A few days ago I trashed a $60 TFT touch panel and a 100 pin Pic32MX while probing voltages not realizing that my multi meter probes were in the current slot instead of a voltage slot.  :palm:
Desoldering the pic and 5 blown SMD IC's was a real joy

I think it's worthwhile to fire off an email to the guy on ebay we bought these units from. For all we know he might have some junk units too bad to sell that may have parts. He seems to have acquired dozens of them anyways. You should post a pic of the damage.


Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on March 08, 2016, 04:36:23 am
And the sad story continues...

After painstakingly removing the VFD properly, I began the process of determining where the parts that fell off might live, there are no silkscreens, and which parts were likely damaged and would need to be replaced.

The board consists primarily of an Intel TN87C196 16-bit microprocessor (OTP) and two Allegro UCN5812 VFD drivers. There is also a MAX773 DC-DC converter (to generate the 12V rail), and some other miscellaneous components. I decided to power up the front-panel board from a bench PSU and try to determine which part was bad. This was easy enough, it's just a 5V rail. At 1A, the supply was still in CC mode at about 2V so I figure there must be a short. Not finding anything obviously getting hot other than the DC-DC converter, which made me suspect one of the 5812s (which I would have guessed anyway), I decided to proceed with resoldering the components that fell off.

The ICL7660 was one of the desoldered parts, and studying its pinout it was pretty easy to determine which space it went in due to the boost capacitor's placement. It was replaced. As I did not want to fully reverse engineer the circuit, I thought I would power the board up again to measure around the pads for the dual FET and determine its orientation. In the process of doing so, Mr Bozo struck again, and I reversed the power supply to the board. Unlike many of HP's well engineered products, the board has no reverse power protection, not that it would normally need it. Getting that dreaded feeling, I went to steal the "spare" FFC connector on the main board to connect it back up. I had previously noticed that the main fan doesn't start for 15s or so when the front panel is disconnected, so I could test the board that way.  I now suspect the main controller has been killed too, as when it's connected to the main board, I get the same delayed startup that happens when the front panel was disconnected, so it seems that the main board can't communicate with it anymore (this was, I think, still working after my initial blunder).

So I'm left in a difficult position on repairing this. I might be able to get a new TN87C196, there seem to be some on eBay that are claimed to be new, however getting the code is likely impossible. I think it's nearly certain that it's dead, so my options are more or less to find a replacement front-panel board from a donor unit, or reassemble it and sell it on as for parts. I don't think it's worth ordering the likely parts I killed the first time around at this point, unless someone can give a story where a 1990s microcontroller survived a reverse voltage for 30s.

I'm still going to try repairing the front panel board as best I can to take some high-res photos for anyone else that may come across having to repair one in the future. Stay tuned.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on March 08, 2016, 06:02:56 am
So I might have actually been saved on this one...the main power supply to the MCU runs through one of the passives that fell off the board and I hadn't reinstalled yet. I realized that I couldn't have tested the front panel board that way after my initial blunder, since the FFC connector was fried. After replacing the passives in the correct spots and powering up through the main unit, I don't get the long fan start delay any longer, it's a more typical 2-3s. The box still doesn't respond on RS232, which is a bit odd to me, but progress!

After powering up that way, I found the lower-left 5812 gets hot, and it was the part I suspected based on what I'd shorted anyway, so a definite direction now. I will order all the candidate ICs - I think they are all pretty easily obtainable and proceed with a repair attempt. The reverse voltage might have fried one of the other bits, but they're cheap and easy to replace compared to the MCU.

Attached is an annotated photo of the board for anyone who comes across this thread in the future.

I've posted the full resolution of that image, plus some other photos, at http://www.gotroot.ca/66311b (http://www.gotroot.ca/66311b) . A blog post will probably come eventually, if I get this thing working again.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on March 10, 2016, 09:16:34 am
I gather everyone is probably tired of my blunders and repair attempts, but one final post...

tl;dr after 6 hours of work tonight, my 66311B is fully operational and now has front-panel outputs!

(http://gotroot.ca/66311b/P1040411-thumb.JPG)

The longer story is that the first thing to replace was the FFC cable, since I ripped that. Parlex 100R8-305B worked, though it's slightly shorter than the stock cable and more care was needed when re-attaching the front panel. Yet another thing I don't really like about the mechanical design of this box is that the flex has to go around a fairly sharp bend as it leaves the front panel, which created a kink at the stiffener and made it easy to break.

First things first, I replaced the obviously burnt UCN5812 with a new HV5812. Having never soldered PLCC by hand before, I didn't realize that this package is the spawn of Satan. After some fiddling around I got that installed. Added two bodge wires to the VFD pins in place of the pads I had damaged while removing the dead IC with a poor technique. A lot of hassle would have been saved if I had a hot air station...

At this point I also elected to replace the MAX773 DC-DC driver (which actually creates a 40V supply, not 12V as I had originally thought), because I thought it was also dead since there was no output on the regulated output pins. In hindsight the removed part may be functional, since the DC-DC in this design uses an external drive transistor and the internal outputs are not used.

These being the parts I suspected most strongly, I decided to give the board another try at this point. With the VFD sitting free and some pressure applied, I could now get all segments to light when powered on. There didn't seem to be any indication of activity on the display, just all segments lit. An hour or two of probing later I was pretty positive that the power supplies, drivers, and microcontroller were working properly. So being stupid, I decided to try soldering the VFD back on, just in case some pins weren't making contact and causing the all-segments issue. Of course this failed, and I had to desolder the thing again.

Now we're here:

(http://gotroot.ca/66311b/P1040397-thumb.JPG)

I should have just replaced the pesky LM339 to begin with, I purchased one and it was cheap and easy insurance. The one on the board seemed to be working, but I replaced it anyway. Immediately the VFD showed signs of life, though I wasn't able to get a proper display until it was soldered down. There wasn't much else left to do. During my previous probing I had already determined that I was pretty sure the transistors and other ICs on the board were working perfectly, so pretty much the last ditch was to power it up and cross my fingers. And lo and behold! It's alive!

(http://gotroot.ca/66311b/P1040402-thumb.JPG)

So on to the front panel output mod. In my rummaging looking for replacement parts, I had found a pair of these Pomona 72913 jacks in red and black from a long abandoned project:

(http://ca.mouser.com/images/fluke/lrg/72913-2_01a_c.jpg)

They were very close to fitting perfectly in the existing front panel cutouts. I did have to enlarge the holes by 1mm or so, but it was an easy fit. Somewhat unfortunate that they are 'safety' jacks, but I felt I would have a hard time mounting the traditional type due to the depth and size of the holes in the plastic. Plus I had them on hand. With the holes enlarged, they mounted easily. I chose to solder directly to the bottom pads of the rear output connector. My first whack at this had the wires interfering with one of the mounting standoffs, so I had to redo it to avoid that. My choice was to bring the 'remote' sense lines from the connector to the front panel and short them directly to the output there. Without adding a switch, this means I won't have remote sense capability, but that was a feature I was unlikely to ever use anyway.

With these jacks there is not much clearance between the chassis and the bottom jack, but it's enough. I would recommend filing the sharp edges off the chassis or adding some rubber or something to avoid damage to the wire.

(http://gotroot.ca/66311b/P1040406-thumb.JPG)

Finally I replaced the broken switch on the rear panel for calibration inhibit. And now I think I'm done breaking things. Time for an Old Fashioned ;). Perhaps a fancy knob will be in my future.

Hope this helps or that someone has enjoyed my repair log, even if maybe I should have created my own thread ;).
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: stuartk on March 10, 2016, 12:01:05 pm
Ve7xen That's a really impressive save :)

I'll likely organize a group buy for knobs and any other Keysight parts when I'm back to the office in a week..

Don't bother getting the feet from Keysight. I contacted them and they are 19$ Cad per FOOT..  Buy them on eBay instead..

More details to come. You can pm me if you are interested. My apologies if I don't respond for a week. Canada is a bit expensive to ship from, so probably this group buy would be best for USA and Canada
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: macboy on March 10, 2016, 01:09:00 pm
...Having never soldered PLCC by hand before, I didn't realize that this package is the spawn of Satan. After some fiddling around I got that installed. Added two bodge wires to the VFD pins in place of the pads I had damaged while removing the dead IC with a poor technique. A lot of hassle would have been saved if I had a hot air station...
Good work on the successful repair.
Next time that you need to replace a PLCC, remember that you are trying to save the board, not the dead device. Clip all the leads off close to the package, remove the legless black blob, then desolder pins one by one easy as pie. Use some braid the clean up the pads, and you are ready to solder on the replacement, which is a much easier task than removal.

stuartk: I am definitely in for one knob in a group buy.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on March 10, 2016, 05:34:25 pm
...Having never soldered PLCC by hand before, I didn't realize that this package is the spawn of Satan. After some fiddling around I got that installed. Added two bodge wires to the VFD pins in place of the pads I had damaged while removing the dead IC with a poor technique. A lot of hassle would have been saved if I had a hot air station...
Good work on the successful repair.
Next time that you need to replace a PLCC, remember that you are trying to save the board, not the dead device. Clip all the leads off close to the package, remove the legless black blob, then desolder pins one by one easy as pie. Use some braid the clean up the pads, and you are ready to solder on the replacement, which is a much easier task than removal.

stuartk: I am definitely in for one knob in a group buy.
Thanks for the tip. This is actually what I tried, but using a sharp x-acto knife to cut the leads, which has worked well for me before on (T)SO packages. The cutting pressure was a bit much and a couple pads tore off, so I switched to heat shielding the rest of the board and using the heat gun... I didn't think to try side cutters which there might just have been enough room for. Next time :).

I actually found soldering the new part quite challenging also. Because of the way the pins curl under the package, there's quite a large gap at the edge of the part between the pin and the pad. Guess I need more practice, so now to find some other stuff to repair.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on March 10, 2016, 06:02:18 pm
I did some further testing on my 66311B regarding the temperature sensitivity. The reference is pretty much stable after a few minutes and doesn't vary much with a changing room temperature so the conclusion is that the rest of the circuitry causes most of the temperature drift and therefore it doesn't make sense to put a better reference chip in the 66311B. Mine has an MC1403 2.5V reference by the way.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on March 10, 2016, 09:36:00 pm
ve7xen - nice job on the repair, and the power jack install. If you have hot air to remove a PLCC device they are quite nice to work with. Installing them can be a bit of a pain if you don't have a fine enough tip or can't get the soldering iron angle needed.

I just got an Agilent 6632A which uses the same controller board as the 66311B, but it allows for full control over current sinking. I dream of finding a firmware rev that allows the same for the 66311B.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: edavid on March 10, 2016, 09:48:06 pm
My choice was to bring the 'remote' sense lines from the connector to the front panel and short them directly to the output there. Without adding a switch, this means I won't have remote sense capability, but that was a feature I was unlikely to ever use anyway.

It's usual to connect the front panel jacks to the sense lines through "small" resistors - then you can still hook up remote sense wires, which apply the real remote load voltage to the sense inputs.

Depending on the design, it can be tricky to figure out an appropriate value of small.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on March 11, 2016, 05:52:01 am
I noticed this in reading the user manual:
Quote
Although the dc source can operate in either mode, it is designed as a constant voltage source. This means that the unit turns on in constant voltage mode with the output voltage rising to its Vset value. There is no command for constant current operation. The only way to turn the unit on in constant current mode is by placing a short across the output and then enabling or turning the output on.

So I decided to do some captures of the turn on behaviour, which might be of interest here. All measurements are done with a 1X probe, and all done with the output enable switch. I don't think that will cause any measurement issues for these, but let me know if I'm wrong about that.

Let's start with unloaded 15V:

(http://gotroot.ca/66311b/66311b-unloaded-15v-riseglitch.png)

Hmm curious glitch there before the supply comes online. I wonder if it's related to the program voltage or load, and if it might be a problem powering very sensitive...stuff that can't handle a ~2.5Vpp 100us spike.

(http://gotroot.ca/66311b/66311b-50R-1A-100mV-riseclose.png)

Nope, doesn't seem to be. Very similar with a 50R load and 100mV program voltage. Looks to be almost exactly 8ms before the main loop starts, during which time the output goes negative, and looks the same regardless of parameters or load (I assume subject to the supply's drive capability). It seems to be related to the output enable/disable switching, as it doesn't appear when going from 0V to 5V with the output enabled. The overshoot also seems to be much more prominent here compared to with a higher output voltage, though it's not quite constant.

On to the 'start in constant current mode' tests. First I decided to test a capacitor directly hooked up to the supply, figuring this would be a challenge for the output amplifier. I selected a nice beefy 6800uF cap from the junk box and set the supply to 14V / 100mA:

(http://gotroot.ca/66311b/66311b-6800uf-100ma-14V-riseclose.png)

So with this load, it looks like it takes 6-7ms for the current loop to kick in and regulate to a constant current. Not shown is charging, which looks nice and linear, and the switch back to CV mode after charging the cap also looks nice and clean, no hint of oscillation or ringing.

Next up is intended to simulate a high-power LED, as 4 1N4007 in series across the supply at 100mA and a 5V set point:

(http://gotroot.ca/66311b/66311b-4x1n4007-100ma-5V-riseclose.png)

This one is very similar, as it takes 6ms for the current loop to kick in. Then we get what looks like a discharge curve down to the constant current. I guess this might be related to diode capacitance or maybe Vf changing as I goes down when we go into CC mode.

Finally the supply into a purely resistive 50R load, first in constant current configuration set for 100mA @ 14V:

(http://gotroot.ca/66311b/66311b-50R-100ma-14V-rise.png)

Wow it's really slow to kick into CC mode with a resistive load! 220ms. My hypothesis is that the loads above would appear as nearly a dead short to the supply, pulling enough current to hit the 'peak' current limiter, and then ending up in CC mode after that. With the resistor, 14V/50R is only 280mA, so it runs that way for a while before the regular loop notices.

Finally a close up of CV mode into 50R, set to 5V/1A (the filenames are wrong on these, oops):

(http://gotroot.ca/66311b/66311b-50R-1A-7V-riseclose.png)

There are a couple more captures with my repair photos at http://gotroot.ca/66311b/ (http://gotroot.ca/66311b/)
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on March 13, 2016, 01:07:33 am
Finally received my banana jacks from china. Did a quick install this afternoon, so far I am pleased with them for $1.48 shipped. I ran the 4 wires and soldered them directly to the back of the banana jacks. Because of the depth of the front plastic face I used a pair of larger washers on the back side along with lock washers and one set of nuts instead of the backing plate included with the banana jacks. The jacks I bought were from ebay # 321513366620 but the price has since gone up. Removing the main board is quick and easy, just make a note/take pics of where all of the connectors plug in.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: stuartk on March 13, 2016, 02:09:15 am
Hi Steve,

Nice banana jacks for the output. Where did you route the sense wires to?
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on March 13, 2016, 02:12:41 am
Hi Steve,

Nice banana jacks for the output. Where did you route the sense wires to?

The sense wires and main current wires are both connected to the banana jacks. So any voltage loss after the jacks will not be compensated for which is fine with me. I used much smaller gauge wire for the sense leads.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: mtdoc on March 13, 2016, 06:25:21 am
Ve7xen and TheSteve -Excellent mods!. 

I'd decided not to add front panel jacks but now I'm tempted.

I especially like the recessed Pomona Jacks. Any ideas of a good source for these?
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on March 13, 2016, 06:54:05 am
You can buy a chinese 10 pack no noname ones for 3.89, ebay # 262238741920
Of course they might be decent, they might be total crap.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: mtdoc on March 13, 2016, 08:21:54 am
You can buy a chinese 10 pack no noname ones for 3.89, ebay # 262238741920
Of course they might be decent, they might be total crap.
Thanks for the link. For that price they are surely low quality. On the other hand, how bad can it be given the very simple function?

I was able to find genuine Pomonas on Digikey (http://www.digikey.com/product-detail/en/pomona-electronics/72930-2/501-1228-ND/1196362) for 2.60 each. I think I'll throw a couple in with my next Digikey order.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on March 13, 2016, 08:49:28 am
At that price I'd go for the real Pomona's too.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: SKPang on March 13, 2016, 10:02:23 am
Quote
I was able to find genuine Pomonas on Digikey (http://www.digikey.com/product-detail/en/pomona-electronics/72930-2/501-1228-ND/1196362) for 2.60 each. I think I'll throw a couple in with my next Digikey order.

The problem with the Pomonas one is you can't attach bare wire to it. For a PSU I would prefer a version that allows bare wire.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: mtdoc on March 13, 2016, 08:02:40 pm
Quote
I was able to find genuine Pomonas on Digikey (http://www.digikey.com/product-detail/en/pomona-electronics/72930-2/501-1228-ND/1196362) for 2.60 each. I think I'll throw a couple in with my next Digikey order.

The problem with the Pomonas one is you can't attach bare wire to it. For a PSU I would prefer a version that allows bare wire.

That's a good point I hadn't considered. I suppose a short banana alligator lead would solve the issue but is less elegant. There's still the Phoenix connector on the back as well.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: timb on March 14, 2016, 01:28:20 am

Quote
I was able to find genuine Pomonas on Digikey (http://www.digikey.com/product-detail/en/pomona-electronics/72930-2/501-1228-ND/1196362) for 2.60 each. I think I'll throw a couple in with my next Digikey order.

The problem with the Pomonas one is you can't attach bare wire to it. For a PSU I would prefer a version that allows bare wire.

Sure you can! Just grab one of these: Pomona MDP Double Banana Plug (http://www.pomonaelectronics.com/pdf/d_MDP-4892-4898_102.pdf)

Simply insert wire and tighten screw. I use them with a few of my power supplies that have banana jacks instead of binding posts. They work great!
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on March 14, 2016, 03:12:24 pm
Quote
I was able to find genuine Pomonas on Digikey (http://www.digikey.com/product-detail/en/pomona-electronics/72930-2/501-1228-ND/1196362) for 2.60 each. I think I'll throw a couple in with my next Digikey order.
The problem with the Pomonas one is you can't attach bare wire to it. For a PSU I would prefer a version that allows bare wire.
Sure you can! Just grab one of these: Pomona MDP Double Banana Plug (http://www.pomonaelectronics.com/pdf/d_MDP-4892-4898_102.pdf)
I don't like these at all. I rather have proper binding posts which take bare wire and 4mm banana. I have modified various pieces of equipment to have such binding posts.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: SKPang on March 14, 2016, 03:37:19 pm
Some of the binding post I've seen doesn't have the hole for the bare wire. I'm tempted to drill a small hole through the thread for the wire myself.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: FrankE on March 26, 2016, 10:50:47 am
I was looking at those earlier for cellphone test and repair and as a general PSU. I found one at £170. I logged in here to look for opinions on the kit and I've saved half of that.

Nice one, thanks
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: SKPang on April 06, 2016, 07:11:52 pm
Got some binding post but it didn't have a hole for the bare wire so I drilled a hole myself.

Didn't want to solder the wires to the PCB so I routed it to the outside. Not as neat but it will do.

Title: Re: My poor mans SMU - The Agilent 66311B
Post by: rrinker on April 06, 2016, 08:12:42 pm
 Are those actual HP binding posts or are they the look-alikes that were posted a few posts back? Now seen on the unit itself, if those are the fakes, they sure seem to have the right look and color to match the rest of the design.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: SKPang on April 06, 2016, 08:18:24 pm
They are not real HP ones. They are from Rapid electronics:

http://www.rapidonline.com/truconnect-24-827-1-grey-4mm-test-socket-solder-connection-60v-24a-red-17-3270 (http://www.rapidonline.com/truconnect-24-827-1-grey-4mm-test-socket-solder-connection-60v-24a-red-17-3270)
http://www.rapidonline.com/truconnect-24-827-2-grey-4mm-test-socket-solder-connection-60v-24a-black-17-3271 (http://www.rapidonline.com/truconnect-24-827-2-grey-4mm-test-socket-solder-connection-60v-24a-black-17-3271)

I like them because the colour matches a bit.


Title: Re: My poor mans SMU - The Agilent 66311B
Post by: FrankE on April 06, 2016, 08:32:37 pm
Good grief! How many tracking numbers can one package have. It cleared customs at CDG (Paris) on Monday.

Tomorrow, maybe.
I've got the missing Phoenix terminals. My one is also missing a front panel.
I had binding posts in my RS order but I took them out to put in my Digikey order but I'm not quite at £50 threshold for  free delivery yet.
I hope there's not too much wrong with it electronically or if there is, it's something I can handle.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on April 06, 2016, 08:40:22 pm
I like the look of the binding posts as well, very much a factory look to them.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: macboy on April 07, 2016, 12:40:12 pm
Got some binding post but it didn't have a hole for the bare wire so I drilled a hole myself.

Didn't want to solder the wires to the PCB so I routed it to the outside. Not as neat but it will do.

...
(https://www.eevblog.com/forum/testgear/my-poor-mans-smu-the-agilent-66311b/?action=dlattach;attach=215211;image)
...
Your sense wires should twist around each other, not around the current-carrying wires. Likewise, the current carrying wires should also be twisted with each other. They way you have done this, current fluctuations will induce voltages in the sense wires, messing with voltage regulation and possibly even causing stability issues.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: SKPang on April 07, 2016, 12:44:17 pm
Thank you macboy, good point. I will take it apart and re do the wiring.

Title: Re: My poor mans SMU - The Agilent 66311B
Post by: FrankE on April 08, 2016, 11:33:57 pm
Got mine today. No front panel, no knob. I already had ordered the Phoenix connectors
I've no supply rails. +15V -15V. The 5V rails are fine, front display.

F308 (5AM), F310 (5AM)  F303 (5AM) F306 (5AM) seem to have blown. I blew the chassis fuse with my DMM lead, d'oh but at least it was at the mains switch so I won't have blown anything in the DC stages  I've put Littelfuse axial fuses on my next RS order  What do they mean by M suffix on their fuse ratings?
Fuse speed is rated on RS by either T  (time delay), F (fast), FF (very fast)

I think I might have 15V, 5V and +15V regulators somewhere, just in case.

Table 3.3 p32 states to use the R431-4 on A1 board as a common. It's not evident which pin that is because there's no pinout marking on the component or board.

The fan is quite loud isn't it? The Papst is rated at 33m3/h 20CFM. Similar sized case fans are up to 16, so I wonder if the volume is a function of the pitch of the  impeller blades or if a lower air change fan would be sufficient.
 
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: FrankE on April 10, 2016, 07:07:38 am
I like the look of the binding posts as well, very much a factory look to them.
Yeah, me too. I don't mind a trailing lead from the back but there isn't strain relief unless one cable ties the test lead to the fan grille.
I found 'binding posts' [they are not binding posts just sockets] , that take shrouded leads Hirschmann SAB 2600 series (M4 thread), 2630 (solder pin), 2640 (solder bucket) , Multi Contact XUB (?M4)  Probably others, though I couldn't see Pomona ones Hope they are a proper 5 way and have the transverse hole for hook up wire.
[EDIT: No they are only sockets, i.e no threading to secure spaded leads, or bind hook up wire, no transverse hole for on the fly hook up wire.
If they can't take binding they ain't binding posts.]

If so, saves having duplicate sets of shrouded and bare leads
Seems odd that these have to be hunted down, I would have thought these would be the norm these days, not the exception.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on April 10, 2016, 07:16:57 am
I used a Pomona # 6883 on a different power supply. They look very similar to what I used on the 63311B but are made of nylon, only 3 dollars or so from Digikey etc and the quality is very nice. They work great for binding posts/banana jacks but certainly do not have a factory look to them.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: FrankE on April 14, 2016, 05:57:51 am
It's back in the game again (well, at least to diagnose).  I replaced the 5A PCB fuses I blew late last night.  I replaced the Papst 12V fan which itself looks like a retrofit with a  San Ace 60 S Series 12V fan (from Farnell). Rated 0.4m³/min (14.1cu.ft/min) 16dBA. It is much quieter and I haven't yet fitted an isolation gasket.
It didn't come with a molex connector attached, (it's a 3 wire BTW) so I had to bodge it on with a connector block as I don't have a Molex crimper yet.
It soon ramps up full tilt despite no/low load i.e having 13.9V across it. Seriously, HP/Agilent is that fan speed really necessary
Input rails are fine.
No idea where to use as the common for the crowbar and reverse. My scope is broke so I can't see the gating. My 289 is away to Fluke, so it's getting a bit of a nuisanse swapping leads.

Now I can't get the output to shift from 8.000V.
I set it there after not previously being able to shift it from some other nominal voltage.
Perhaps it's on remote. "Address 0" is displayed in the boot sequence and I was fiddling in that menu.
I can't see the firmware option
Hmm, RTFM etc.

edit: oops, I forgot one of the 125mA  fuses had popped

I can't see any full schematics anywhere so there's a lot of guesswork
Once I get it fully working, would I get any better precision/ performance if I replaced the LM 78xx CGT and LM 79xxCGT the +/- 4% with LM 78xxACTG and LM79xxACTG the +/- 2% versions or are the subsequent stages taking care of the precision?

Title: Re: My poor mans SMU - The Agilent 66311B
Post by: FrankE on April 24, 2016, 10:48:05 am
Yay, repaired it. The crowbar circuit was gone (broken trace). Oh well, didn;t need those 2% LM 78xx LM79xx ACTG regulators. Might use them to build a 5680 10MHz Rb frequency standard.
It's running nice and quietly with a new fan
It has firmware A01.08.
What's to be gained from changing to a later ROM revision e.g. A 02.04 Any additional functionality?
I don't have a GPIB converter and they are horrendously expensive second-hand, so I'd need to buy an Atmel AT27C2048 and see if the local hackspace has an EEPROM programmer.
What can I do with the serial port? Is there any freeware one can use to control the 63311B or log?
I'm not sure how the calibration is but I get my 289 back from Fluke within a couple of days, which I assume will come with some sort of post repair/board change factory cal.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on April 24, 2016, 04:12:15 pm
Nice to hear you've brought it back to life!
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: FrankE on April 29, 2016, 06:58:16 pm
Nice to hear you've brought it back to life!

Many thanks for the heads up on the deal.
It was my own fault, I might have broken it by allowing a scalpel to drop in it.
It's running really quietly 15.386V 2.6A powering a screenless laptop I found, so worth changing the fan.

This firmware upgrade. Is it worth it? I have the through hole version A01.08. I read SMT was introduced in 1999. Is 02.04 even compatible?
I got an Atmel IC today from RS, I don't have an EEPROM programmer and I couldn't justify buying even a TL866 this month but someone said they could do it with an Arduino. Whether 'could' is 'will' is yet to be seen.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: TheSteve on April 29, 2016, 07:10:53 pm
No idea on the firmware update - I'd be tempted to leave it though, especially if you don't have a programmer handy. I love updating firmware on stuff but there is always the risk/reward factor. I'd also backup the calibration data before messing with it if you do attempt it.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nidlaX on June 10, 2016, 06:59:40 pm
Does anyone know how to remove the front panel board from the front panel chassis? The service manual suggests I pull the board back 1/8th of an inch near the encoder, but I can't feel any compliance and fear breaking the board if I do so.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: feedback.loop on June 10, 2016, 08:34:35 pm
Does anyone know how to remove the front panel board from the front panel chassis? The service manual suggests I pull the board back 1/8th of an inch near the encoder, but I can't feel any compliance and fear breaking the board if I do so.

First you need to undo the nut on the encoder, then bend the tab on the board (see the pic) slightly so that it can go past the plastic stop, then you must be able to slide the board a few millimeters from under the hooks.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nidlaX on June 10, 2016, 09:03:58 pm
Does anyone know how to remove the front panel board from the front panel chassis? The service manual suggests I pull the board back 1/8th of an inch near the encoder, but I can't feel any compliance and fear breaking the board if I do so.

First you need to undo the nut on the encoder, then bend the tab on the board (see the pic) slightly so that it can go past the plastic stop, then you must be able to slide the board a few millimeters from under the hooks.
Thanks! Not sure how I missed the encoder being secured to the front panel chassis (although it's not mentioned in the disassembly procedure). :palm:
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: ve7xen on July 06, 2016, 04:10:03 am
I decided that not having a knob was unacceptable, and have been wanting to try having small parts printed by a 3D printing house, so figured modelling and having a knob printed would be a good exercise.

Based on the photos here and at the Agilent Find-A-Part, plus some measurements of my actual unit, I did my best at a model in OnShape (shown is not exactly what was printed, I made some refinements):
(http://gotroot.ca/media/agilent_knob_model.jpeg)

I had the design printed by Sculpteo, using their SLS process, in 'polished beige plastic'. With express shipping it cost about $15 and arrived in a week.

Overall I am happy with the result. The only flaw was that the printing process left about 0.1mm extra clearance around the knob shaft. I had expected 'expansion' and not 'shrinkage' so had modeled to exactly the shaft dimensions, so now it's a bit sloppy. The STL I exported was also somewhat 'low res', resulting in the stepped appearance. I have changed the model to make the knob about 1mm taller, since it seems a bit shorter than the real one, added 0.1mm total interference on the shaft dimensions to make it tighter, and exported at a higher fidelity. I don't intend to reprint, as I think what I've got will be perfectly functional.

(http://gotroot.ca/media/agilent_knob_photo1.jpg)
(http://gotroot.ca/media/agilent_knob_photo2.jpg)

I have made the model public on OnShape, so you can copy it to your own workspace and modify as you see fit:

https://cad.onshape.com/documents/2770017399f21096171bcc75/w/82d82831cbaa64cec2e5b5a7/e/d79452ab36c21b057637b9b5 (https://cad.onshape.com/documents/2770017399f21096171bcc75/w/82d82831cbaa64cec2e5b5a7/e/d79452ab36c21b057637b9b5)

You can also download an STL file for direct printing here (note this is a refined model that I have not myself printed):

http://gotroot.ca/media/agilent_knob_model.stl (http://gotroot.ca/media/agilent_knob_model.stl)
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: pigrew on October 03, 2016, 04:52:22 pm
I started trying to learn about Windows Presentation Framework over the weekend. I mostly can do the GUI part now, but data binding is still a mystery. Maybe next week I'll figure that stuff out.

Anyway, the software is able to talk to my 66309D pretty well.

<https://github.com/pigrew/HP663xxCtrl>

I'm not yet posting any builds, as there are a few small issues that need to be fixed (like adding a Save button). But, it's in a somewhat usable state. It'll probably work with any of the 663xx series (but I forgot to tell it about the 66312A and 66332A). If you find issues with its ability to talk to other models, let me know or send me a pull request on GitHub.

I tried to replicate Agilent's "data log" feature, but I'm not able to see most of my advertisement packets, so I'm not sure how useful it would be for me to estimate energy usage. Their software restricted it to the 66319/66321, but I'm not sure why. The user manual didn't describe any commands supported by the newer hardware or firmware v3 that would seem to be required.

The attached is the current draw of a TI BLE microprocessor. I've triggered it on an advertisement packet. It's transmitting on three different channels.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: pigrew on October 03, 2016, 04:55:11 pm
One other request:

My SMU's front panel lets me select "AUTO" current ranging. What's the SCPI command to enter and leave auto-range mode? I couldn't find it in the manual.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: samofab on October 03, 2016, 07:23:24 pm
I can report that the software compiles and connects to my 66309D.
Few bugs to iron out... in mine the decimal points for the display of current voltage and current on the left are missing (displaying 100000 instead of 1.0V)
Otherwise it looks totally great! Finally an easy way to use our 66309's & Co to their full potential!

Info for somebody else who'll try to compile it: VisaComLib is in file
GlobMgr.dll found in C:\Program Files (x86)\IVI Foundation\VISA\VisaCom
at least on my computer.

thumbs up!
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: samofab on October 03, 2016, 08:37:27 pm
My SMU's front panel lets me select "AUTO" current ranging. What's the SCPI command to enter and leave auto-range mode? I couldn't find it in the manual.

Perhaps you can look in strings section of the firmware if there's an undocumented SCPI command.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: pigrew on October 03, 2016, 09:22:08 pm
My SMU's front panel lets me select "AUTO" current ranging. What's the SCPI command to enter and leave auto-range mode? I couldn't find it in the manual.

Perhaps you can look in strings section of the firmware if there's an undocumented SCPI command.
I tried downloading the firmware image posted in this thread, but couldn't find any strings in it. Is the image obfuscated or compressed?

Sent from my LG-D850 using Tapatalk

Title: Re: My poor mans SMU - The Agilent 66311B
Post by: pigrew on October 04, 2016, 03:30:31 am
Few bugs to iron out... in mine the decimal points for the display of current voltage and current on the left are missing (displaying 100000 instead of 1.0V)

I think this must have to do with my assumption that everywhere is like the America, and uses periods as decimal points.

I just tweaked a few things, and more things will now show up as commas for you...

But, for storing data files (like CSV), I assume that you would want to use periods as decimal points?

Were there issues with parsing numerical responses from the instrument? I probably should tell it to use the InvariantCulture more often....

(And yes, it still has quite a few small bugs that I can think of, but it nearly working well enough for my needs)
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on October 04, 2016, 08:17:33 pm
But, for storing data files (like CSV), I assume that you would want to use periods as decimal points?
Getting that right is a study in it's own. The quickest solution is to make sure you use the local language setting. This may require extra initialisation in your software.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: pigrew on October 04, 2016, 11:35:15 pm
But, for storing data files (like CSV), I assume that you would want to use periods as decimal points?
Getting that right is a study in it's own. The quickest solution is to make sure you use the local language setting. This may require extra initialisation in your software.

I've made the GUI and the communication with the instrument better respect the system's culture.

However, my question was regarding data files. I'm thinking that the data files should be independent of what computer wrote them? Also, I usually expect commas to separate fields in CSV files, but this would conflict with using a comma as a decimal point.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on October 04, 2016, 11:46:03 pm
What works for me when dealing with CSV, configuration, XML, etc files is using a semi-colon to seperate fields and a period as a decimal seperator. In order for this to work I wrote a some C/C++ routines which override the locale setting and process/print numbers with periods as decimal seperators. Displaying is another thing. If all goes well the programming language should detect the selected locale and format numbers accordingly.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: samofab on October 05, 2016, 07:17:51 am
Your last commit has a bug in ApplyProgram_Click.

you replaced
if (!Double.TryParse(CH1VTextBox.Text, out details.V1)) {
with
if (Validation.GetHasError(CH1VTextBox) || Validation.GetHasError(CH1ITextBox)) {

so you don't actually populate the details with values in textbox fields.

If you give me commit rights, I can fix small errors like this.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: pigrew on October 05, 2016, 01:50:35 pm
Your last commit has a bug in ApplyProgram_Click.

......

so you don't actually populate the details with values in textbox fields.


Too late at night. Committed untested code. I think that it's fixed now, and I found a number of other bugs. I was trying to switch the fields over to using a ViewModel (I've never used one before), as the easiest fix for handling number formatting issues. It also let me add range validation checks somewhat more easily.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: samofab on October 05, 2016, 02:33:22 pm
yea, it works now.
found another bug.. if you try to acquire much more than 3000 points the read operation timeouts at ReadIEEEBlock
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on October 05, 2016, 10:25:35 pm
@pigrew: your software looks interesting. When I have some time I'll try it.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: pigrew on November 09, 2016, 10:14:44 pm
I've put the software on the back-burner for the last few weeks. I ended up buying a similar Keithley supply (2304A), and will write a driver to also control that instrument with the same software. In the mean time, I'm fixing a few minor bugs I've found.

I also found that there is a native .Net driver interface for visa (ivi.net). I had been using IVI VISA COM. It looks like IVI VISA.Net has been supported for the last year or so, and makes it much more clear how to write drivers that don't have memory leaks and other issues. So, unless there are objections, I'll transition to using Ivi.net. It looks like it is supported on all recent versions of Windows (NI Visa 15+, Keysight IO 17.2+).

I promise to post a build of the software in the next week, once known issues are fixed and Keithley support is added.

Since it'll support other instruments, I'll make a new thread for the software (and post a link here).
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: kaz911 on November 09, 2016, 11:45:45 pm
I decided that not having a knob was unacceptable, and have been wanting to try having small parts printed by a 3D printing house, so figured modelling and having a knob printed would be a good exercise.

Based on the photos here and at the Agilent Find-A-Part, plus some measurements of my actual unit, I did my best at a model in OnShape (shown is not exactly what was printed, I made some refinements):
(http://gotroot.ca/media/agilent_knob_model.jpeg)

I had the design printed by Sculpteo, using their SLS process, in 'polished beige plastic'. With express shipping it cost about $15 and arrived in a week.

Overall I am happy with the result. The only flaw was that the printing process left about 0.1mm extra clearance around the knob shaft. I had expected 'expansion' and not 'shrinkage' so had modeled to exactly the shaft dimensions, so now it's a bit sloppy. The STL I exported was also somewhat 'low res', resulting in the stepped appearance. I have changed the model to make the knob about 1mm taller, since it seems a bit shorter than the real one, added 0.1mm total interference on the shaft dimensions to make it tighter, and exported at a higher fidelity. I don't intend to reprint, as I think what I've got will be perfectly functional.

(http://gotroot.ca/media/agilent_knob_photo1.jpg)
(http://gotroot.ca/media/agilent_knob_photo2.jpg)

I have made the model public on OnShape, so you can copy it to your own workspace and modify as you see fit:

https://cad.onshape.com/documents/2770017399f21096171bcc75/w/82d82831cbaa64cec2e5b5a7/e/d79452ab36c21b057637b9b5 (https://cad.onshape.com/documents/2770017399f21096171bcc75/w/82d82831cbaa64cec2e5b5a7/e/d79452ab36c21b057637b9b5)

You can also download an STL file for direct printing here (note this is a refined model that I have not myself printed):

http://gotroot.ca/media/agilent_knob_model.stl (http://gotroot.ca/media/agilent_knob_model.stl)

Hmm - I think Keysight spares quotes about $3.86 for the dial :) when you look for spares using the part number. I got 66311b from Ian for GBP 40,- without Dial knob - so I looked it up. But I then remembered i had an old E3610 panel in the scrap pile - and that has the same dial/knob so I solved it. But nice work making one - I'll try and print it on my Zortrax next time I turn it on to see how it does on ABS.

The 66311b I got from Ian was non functional - and it was a 120v unit - someone had probably plugged into 230/240 V uk supply. 1 main fuse and one onboard through hole 5A fuse later - the thing is now spinning but noisy as h.. :) But very precise and works well.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: HighVoltage on November 10, 2016, 09:52:36 am
- the thing is now spinning but noisy as h.. :) But very precise and works well.

If you add a 100 Ohm resistor in line with the fan supply, it gets much quieter and still has plenty of air flow.
Or you use an ultra quiet fan with built in temperature control.
I have two of these and they are both very quiet now.

Title: Re: My poor mans SMU - The Agilent 66311B
Post by: georgd on July 07, 2018, 07:16:05 am
As owner of a 66311B unit with dim display finally decided to replace it with a new one. A seller on ebay offers many types of VFD
 replacement displays for HP power supplies.

The 1st one is for $130:
https://www.ebay.com/itm/HP-Agilent-Keysight-VFD-For-66311A-66312A-6632A-Vacuum-Fluorescence-Display/123034228542?hash=item1ca569573e:g:meYAAOSwhktas22x (https://www.ebay.com/itm/HP-Agilent-Keysight-VFD-For-66311A-66312A-6632A-Vacuum-Fluorescence-Display/123034228542?hash=item1ca569573e:g:meYAAOSwhktas22x)

The 2nd one is for $85:
https://www.ebay.com/itm/HP-Agilent-Keysight-VFD-For-6634B-Vacuum-Fluorescence-Display/122895199356?hash=item1c9d1fec7c:g:cy0AAOSw4PxaTZug (https://www.ebay.com/itm/HP-Agilent-Keysight-VFD-For-6634B-Vacuum-Fluorescence-Display/122895199356?hash=item1c9d1fec7c:g:cy0AAOSw4PxaTZug)

Only differences I observed is a tiny  bars under sign "OUTPUT AC +DC" in the rightmost lowest corner.
The 66311A version's sign "AC +DC" are underscored but on 6634 version I do not see it.

Do I have to pay 50% for dedicated display?

Georg

Title: Re: My poor mans SMU - The Agilent 66311B
Post by: hakko on October 05, 2019, 02:06:03 pm
Hi! Anyone knows a hack to enable rs232 interface on 66309D series?
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: nctnico on December 25, 2019, 10:21:42 pm
I finally did some hacking on my Agilent 66311B. The biggest let down is the loud fan but no binding posts on the front panel was also lowering the apeal of this otherwise very nice PSU. The PSU is just too good to leave it sitting unused in a corner so I decided to do some hacking to it. First I put some standard binding posts on the front panel and made a cable which connects the bindings posts to the front. I used seperate sense wires which connect at the binding posts.
[attachimg=1 width=800]
I used white braided sleeving (cheap from Ebay) and glue lined heatshrink tubing (also cheap from Ebay) to make a nice wire loom which I then snaked through the PSU. The green plug goes into the output header at the rear of the PSU.
[attachimg=3 width=800]

Last but not least I replaced the fan. I used a Noctua NF-A6x25 FLX (60x60x25mm) fan which has half the airflow and pressure compared to the original fan. But since my PSU only has 1 channel and HP/Agilent tends to oversize the fans anyway I'm sure it won't be a problem. The fan is a direct replacement which plugs in with the supplied cable.
[attachimg=2 width=800]
The original fan has a piece of FR4 sitting between the heatsink and the fan. My guess is that this is to protect the wires from the fan. The Noctua fan however has the wires deeper into the fan's housing to they can't touch the heatsink.

The end result is very good. The noise from the power supply went from obnoxious to almost whisper quiet. At full load the fan spins at the maximum RPM and at that point it becomes audible but the amount of noise is very low.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: JxR on December 26, 2019, 07:41:20 am
Last but not least I replaced the fan. I used a Noctua NF-A6x25 FLX (60x60x25mm) fan which has half the airflow and pressure compared to the original fan. But since my PSU only has 1 channel and HP/Agilent tends to oversize the fans anyway I'm sure it won't be a problem.

I have the same fan in my 66321B.  It is so quiet the first time I turned it on I thought it must have gotten disconnected during the reassembly.  It really does make a huge difference.  I never did an extended load test at 3A to see if it would overheat with the loss in airflow.  I did test it at 1.5A for about 15mins after I first installed it, and it performed fine.

Now if I could just find a solution to the fan in my Keithley 238.  All attempts to quiet that monster have failed.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: JxR on December 26, 2019, 10:38:03 pm
I took the 66321B up to a 30W load today with the Noctua NF-A6x25 FLX installed.  This was over the course of about 30mins, with a load of 30W for about 10mins.  The overtemp protection did not kick in.  So, it seems in a room at ~21C 30W is fine. 

I don't plan to test it up to the max @45W since it exceeds my personal needs for the supply.  This unit is not my main power supply and I rarely would need more than 15W out of it.  I think most people with a supply in the 663xx family would be very happy with this fan.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: mark03 on December 27, 2019, 02:12:50 am
I have a couple of this model's big brother, the 66332A (20V, 5A).  They are more of a pizza-box size but have the same wind-tunnel heat sink and deafening fan noise.

You have inspired me to investigate a slower/quieter fan.  I would definitely use them more if they weren't so loud.
Title: Re: My poor mans SMU - The Agilent 66311B
Post by: kirill_ka on September 25, 2020, 09:43:12 pm
Wow it's really slow to kick into CC mode with a resistive load! 220ms. My hypothesis is that the loads above would appear as nearly a dead short to the supply, pulling enough current to hit the 'peak' current limiter, and then ending up in CC mode after that. With the resistor, 14V/50R is only 280mA, so it runs that way for a while before the regular loop notices.
I know that post is 4.5 years old... I've bought an older version of 66311B (which is called "through hole pcb" in the service manual). Initially I thought that slow switching to CC mode is a fault of my unit. Especially after the seller confirmed that his 66311B is faster. Then it appeared that he was using a newer revision for the test.
While trying to solve the "issue" I found that the main analogue PCB is identical to the HP 66312B. And it does have schematics in the service manual! It looks like HP engineers deliberately sacrificed CC mode  in favor of peak current performance. The attached picture shows the main differences in current control circuit.