Test Equipment Anonymous (TEA) group therapy thread

[Neomys Sapiens]

Also, FedEx just delivered a box from Rigol in Beaverton, Oregon. A post on that acquisition is forthcoming.

This is just too much. That should be illegal!
 

[tautech]

Also, FedEx just delivered a box from Rigol in Beaverton, Oregon. A post on that acquisition is forthcoming.

This is just too much. That should be illegal!
 

Agree.
It seems so wrong that Chinese made goods now come from such an infamous location, the home of Tek and Leopold optics. 

[duckduck]

Also, FedEx just delivered a box from Rigol in Beaverton, Oregon. A post on that acquisition is forthcoming.

This is just too much. That should be illegal!
 

Agree.
It seems so wrong that Chinese made goods now come from such an infamous location, the home of Tek and Leopold optics. 

Technically, Rigol NA is located in Portland, Oregon, but they are only a 15 minute drive from the Tektronix campus. It is clear that Rigol wants to capitalize on the local talent AKA "poaching". Analog Devices has a building near the Tektronix campus. I'm sure that Tek and Rigol share some suppliers. It's probably very handy for Rigol to be able to meet with local suppliers in person. In any case, my trolling has had the desired effect 

EDIT:

Rigol says:

RIGOL’s headquarters is in Suzhou China with a R&D center in Beijing. There are three international subsidiaries in Beaverton, OR, United States, Munich, Germany and Tokyo, Japan. Some 400 employees are serving our customers in more than 60 countries and regions worldwide.

[Neomys Sapiens]

I had another look at the B1012 hybrid multimeter in order to trace the components involved with the lowest resistance range and made an interesting discovery on the side: the presence of an AD636 means that it is a RMS meter, which is not hinted in any way on the front panel. Now it must be fixed for sure! And I'm very curious whether this applies to the analogue movement too.

[Specmaster]

Merry Christmas everyone.

[TERRA Operative]

So, my boss just told me to choose something for my Christmas bonus, a substantial Christmas bonus (I've saved him a lot of money with my skills, so he's giving me some payback, in a good way).

I'm thinking of getting a Siglent scope to sit next to my Siglent spectrum analyzer. What do people think about the SDS2104X Plus?

[ch_scr]

I think (depending on the size of the bonus), the SDS2104X HD is even nicer 

[TERRA Operative]

Ooof, if only my bonus were that big....

[McBryce]

Ooof, if only my bonus were that big....

Then my suggestion of a Keysight MSOX6000 Series is probably out of the question too?

McBryce.

[TERRA Operative]

I'll get the 6GHz model.

[Mortymore]

New acquisition:

Rigol DG812 2-channel 10/5 MHz AWG

This is the 2-channel version of their cheapest DG811 model. I bought it for USD215 (delivered) from Rigol off of their clearance page, which is worth checking out every now and then if you live in the USA.

https://www.rigolna.com/clearance/

...

For Europe  Rigol has a "Promotions" page.

https://rigolshop.eu/promotions.html

I'm thinking maybe buying a Siglent SDM3055 bench meter though, but from them I'm not aware of any (current) promotions.
By any chance, anyone knows about current discounts on any European webstore for bench meters?

If not sooner, Merry Christmas to you all

[tautech]

So, my boss just told me to choose something for my Christmas bonus, a substantial Christmas bonus (I've saved him a lot of money with my skills, so he's giving me some payback, in a good way).

I'm thinking of getting a Siglent scope to sit next to my Siglent spectrum analyzer. What do people think about the SDS2104X Plus?

Bang for buck on current promotion is really good value.....$400 off ! With additional options too.

But.....if someone was offering a leg up into one the HD with additional options and BW upgrade would really tempt me, even If I had to chip in too.
Only had one HD through our hands thus far and it's a really nice DSO but unfortunately a bit of a step in price from the X Plus. 
If you do jump on any of these models do it before years end when the promo ends and grab the MSO option also on promo with a new DSO.
You might think another $220 is a stretch but at this price this the only chance as it must be bundled with a new unit.
Shit easy to hack the X Plus too, the HD not so much as it's not public yet. 

[Vince]

Ballantine 320A TRMS VTVM

We have great news to report at Vince's old junk lab ! 

Well to be honest it was last evening's news but it was 00H45 so I went straight to bed. As always I lose track of time quickly as soon as I am doing something at the bench.

Anyway. So after the first power up the other day, and cleaning the glass ware, it was looking half decent inside, and I knew it had life in it. The needle of the meter movement would move, although it would do all sorts of crazy shit depending on what range you selected. So it was promising but not quite there...

So last evening did some more cleaning : the front panel. Looks much engaging now. You don't feel the need to wear gloves to operate it any more. Looks quite nice actually, it's in good nick.

Then electroniks-wise, tried to check supply voltages to see if there was a gross failure anywhere. Manual covers only the type 320 which is not the same as my 320A sadly. It's close enough topology-wise, but not close enough in the details to be used for accurate troubleshooting. Number of tubes is different, types of tubes used is different for the most part, layout on the chassis is different....

So the schematic could only give me a rough idea of how things are put together, but I could not rely on it for the details. Plus, it's hard to read /decipher anyway, the quality of the scan being not that great...
Also the schematic makes zero mention of component values, only designators, which is a major pain.

So I had no clue what actual voltages levels I should get, nor where to measure them... so I could only do basic sanity checks.
I measured DC and AC/ripple voltage across all the big filter can caps in the power supply section. Found tube-compatible voltage levels, and low ripple.
Checked the voltage on all pins of all tube sockets to make sure I had some high voltage on all of them... I did.
Also, all tubes do light up / glow, which is a good start.

Then powered it off.

Removed all tubes one by one, squirting some contact cleaner into the sockets, then exercising the tubes / pins in the sockets a few times.
Some contact cleaner in the wafer switches, only two, the range switch and "mode" switch. Exercised them extensively.

Then tested the instrument....  I was well rewarded. Needle does not do any crazy shit any more. It does what you expect it to do.
Using my HP 33XXX something, I tested the instrument on all the ranges that the HP could manage, i.e not much 
I tested starting from the 100mV range because the HP can't go lower than 35mVrms or something, ridiculous. So that's 70mVrms really, because 35mV is into 50ohms... but the DUT is 10Meg impedance..
Then the HP can go only up to 3.5Vrms / 7Vrms high impedance, so I could test up to the 10V range full scale, no more.

I don't even know if the HP output is leveled or not ? I bet it's just "open loop", and you get what you get... and you do'nt get upset ?
Anyway, I don't have anything better so I went with that.

The result is incredible.... the VTVM read within spec in all the ranges that I tested ! 
It read consistently a tad low, but still within spec. ..... this thing is 60 years old, sat in storage for the past 25 at the sellers house, and the 10 or 20 years before that, most likely also in storage at Aerospatiale where it came from.... I power it up... and not only does it work, but it's within spec. That's quality engineering and build for you ! 

So imagine what it could do if I played with a trimmer or two here and there to calibrate it hmmm....

Anyhow much of that error is maybe due to the HP sig gen itself ? I don't know.

So here are the numbers. I fed a 1kHz sine wave, on ranges above 0.3mV, in which case the stated accuracy is 2%.
Depending on voltage levels and selected range, I get it looks like, accuracy between 1% and 2%... so it's in spec.

Range     Applied     Measured
          voltage     on VTVM
- - - - - - - - - - - - - - - -
100mV     100mV       98mV
300mV     300mV       295mV
1V        1V          0.99V
3V        3V          2.96V
10V       7V          6.9V


So basically I now have a cleanish instrument, that basically works out of the box... zero caps replaced, zero tube replaced, zero anything. Zero cost.
So if I can flog it for 50 Euros it would be all profit. If nobody wants it, might keep it a for little bit now that it looks nice / clean, and works fine...

Oh forgot, look how it's made underneath the chassis...it looks incredibly modern. This thing is old enough to have a shouldered rectifier tube, yet on the underside it has circuit boards, and state of the art fiber glass boards at that !    One of them even has a card edge connector.


OK so now onto the next piece of TE... what will I pick... place your bets....

[Swainster]

Well, I'd like to pop my TEA cherry by exclaiming "bah humbug!", while coughing on the burnt electronics haze that has suddenly invaded the lab. Once the acute stink had subsided, my nose led me to the front left side of one of my boat anchors, where sure enough, you guessed it, tantalum carnage has spontaneously erupted.

Just for fun, can anyone recognise what piece of kit the tant' is attached to?

[m k]

For Labor I ordered T727 something, from China also.
Not exactly sure how it fits since there seems to be different inserts.

T727 is here.
It has wrong width, too narrow but not a problem.
Depth seems to be correct, same with prong width, holes are too thin though.
So finally it can be used since ceramic part is correctly sized.

Two options then.
I think I'll try China side and try how their male part fits to the machine.

https://www.superbheater.com/materials-and-fitting/high-temperature-plugs/aluminium-connector-2-pin-high-temperature.html

[TERRA Operative]

So, my boss just told me to choose something for my Christmas bonus, a substantial Christmas bonus (I've saved him a lot of money with my skills, so he's giving me some payback, in a good way).

I'm thinking of getting a Siglent scope to sit next to my Siglent spectrum analyzer. What do people think about the SDS2104X Plus?

Bang for buck on current promotion is really good value.....$400 off ! With additional options too.

But.....if someone was offering a leg up into one the HD with additional options and BW upgrade would really tempt me, even If I had to chip in too.
Only had one HD through our hands thus far and it's a really nice DSO but unfortunately a bit of a step in price from the X Plus. 
If you do jump on any of these models do it before years end when the promo ends and grab the MSO option also on promo with a new DSO.
You might think another $220 is a stretch but at this price this the only chance as it must be bundled with a new unit.
Shit easy to hack the X Plus too, the HD not so much as it's not public yet. 

Ah, thanks for the heads-up, will add it to the order.

[Ice-Tea]

HP  11848A Phase Noise Interface. Powered up nicely... for a bit. 

Popping the hood after popping smoke:



The main suspect, obviously, is the mains input section, hidden behind the shield on the right. Not being able to wiggle the cover out, I was already preparing some choice curse words. No need, though, the battery of RF gizzmos blocking the extraction can be removed without any tools. Better:



And to the surprise of absolutely nobody:



Replaced and resleeved:



One completely knackered BNC. Can't be bother to source a replacement, shipping this off for auction.

[factory]

Ballantine 320A TRMS VTVM

We have great news to report at Vince's old junk lab ! 

Well to be honest it was last evening's news but it was 00H45 so I went straight to bed. As alwyas I lose track of time quickly as soon as I am doing something at the bench.

Anyway. so after the first power up the other day, and cleaning the glass ware, it was looking hald decent inside, and I knew it had life in it. The needle of the meter movement would move, although it would do all sorts of crazy shit depending on what range you selected. So it was promising but not quite there...

So last evening did some more cleaning : the front panel. Looks much engaging now. You don't feel the need to wear gloves to operate it any more. Looks quite nice actually, it's in good nick.

Then electroniks-wise, tried to checked supply voltages to see if there was a gross failure anywhere. Manual covers only the type 320 which is not the same as my 320A sadly. It's close enough topology-wise, but not close enough in the details to be used for accurate troubleshooting. Number of tubes is different, types of tubes used is different for the most part, layout on the chassis is different....

So the schematic could only give me a rough idea of how things are put together, but I could not rely on it for the details. Plus, it's hard to read /decipher anyway, the quality of the scan being not that great...
Also the schematic makes zero mention of component values, only designators, which is a major pain.

So I had no clue what actual voltages levels I should get, nor where to measure them... so I could only sanity checks.
I measured DC and AC/ripple voltage across all the big filter can caps in the pwoer supply section. Found tube-compatible voltage levels, and low ripple.
Check the voltage on all pins of all tube sockets to make sure I had some high voltage on all of them... I did.
Also, all tubes do light up / glow, which is a good start.

Then powered it off.

Removed all tubes one by one, squirting some contact cleaner into the sockets, then exercising the tube / pins in the sockets a few times.
Some contact cleaned int eh wafer switches, only two, the range switch and "mode" switch. Exercised them extensively.

Then tested the instrument....  I was well rewarded. Needle does not do any crazy shit any more. It does what you expect it to do.
Using my HP 33XXX something, I tested the instrument on all the ranges that the HP could manage, i.e not much 
I test from the 100mV range because the HP can't go lower than 35mVrms or something, ridiculous. SO that 70mVrms really, because 35mV is inot 50ohms... the DUT is 10Meg impedance..
Then the HP can go only up to 3.5Vrms / 7Vrms high impedance, so I could test up to the 10V range full scale.

I don't even know if the HP output is leveled or not ? I bet it's just "open loop", and you get what you get... and you do'nt get upset ?
Anyway, I don't have nay better so I went with that.

The result is incredible.... the VTVM read within spec in all the ranges that I tested ! 
It read consistently a tad low, but still within spec. ..... this thing is 60 years old, sat in storage for the past 25 at the sellers house, and the 10 or 20 years before that in storage at Aerospatiale where it came from.... I power it up... and not only does it work, but it's within spec. That's quality engineering and build for you ! 

So imagine what it could do if I played wit ha trimmer or two here and there to calibrate it hmmm....

Anyhow much of that error is due to the HP itself ? I don't know.

So here are the numbers. I fed a 1kHz sinwe wave, on ranges above 0.3mV, i which case the stated accuracy is 2%.
Depending on voltage levels and selected range, I get it looks like, accuracy between 1% and 2%... so it's in spec.

Range     Applied     Measured
          voltage     on VTVM
- - - - - - - - - - - - - - - -
100mV     100mV       98mV
300mV     300mV       295mV
1V        1V          0.99V
3V        3V          2.96V
10V       7V          6.9V


So basically IO now have a cleanish instrument, that basically works out of the box... zero caps replaced, zero tube replaced, zero anything. Zero cost.
So if I can flog it for 50 Euros it would be all profit. If nobody wants it, might keep it a for little bit now that it looks nice / clean, and works fine...

Oh forgot, look how it's made underneath the chassis...it looks incredibly modern. This thing is old enough to have a shouldered rectifier tube, yet on the underside it has circuit boards, and state of the art fiber glass boards at that !    One of them even has a card edge connector.


OK so now onto the next piece of TE... what will I pick... place your bets....

I'm impressed, the last couple of HP VTVM I worked on needed a few caps (some were open) changing, had a worn out choob in one of them too, it had grid leakage (even after the paper cap was changed).
I would leave it as is, unless you had equipment to check all ranges, plus the manual gives little away about calibration, except sending it back to them.  Did you try it with any non sine waveforms.

Let us know if you don't get any takers locally.

My guess of the on the next TE is the Philips PM2440, which will either be full of good film caps, or if it's old enough, full of tar covered paper crap. 

David

[factory]

For Labor I ordered T727 something, from China also.
Not exactly sure how it fits since there seems to be different inserts.

T727 is here.
It has wrong width, too narrow but not a problem.
Depth seems to be correct, same with prong width, holes are too thin though.
So finally it can be used since ceramic part is correctly sized.

Two options then.
I think I'll try China side and try how their male part fits to the machine.

https://www.superbheater.com/materials-and-fitting/high-temperature-plugs/aluminium-connector-2-pin-high-temperature.html

I'm surprized any of it fits, given the 35A rating  (which I find hard to believe knowing the usual over-inflated ratings on china stuff).
Guessing it's one of the old connectors on here (which has probably already been mentioned); https://www.plugsocketmuseum.nl/PowerCord2.html or here: https://www.plugsocketmuseum.nl/ApplConn_classic2.html.

David

[factory]

An update on the Advance DMM2 with defective custom IC (IC3).

Part 1, testing the inverting latch and multiplexer stages, using some BCD switches acquired from the last junk-fest.
This sort of worked, but I had the numbers in the wrong order on the display.





This was traced to the differences between the PQ output sequence & the 74x153 BCD sequence.



Bit of wiring correction later.





Part 2, testing the counter stage, for some reason I forgot to order any 74HCT390s in through hole form.  Had to make do with 7490s, which somehow worked OK with the +5V rail loaded down to about 4V, a bit more searching found three out of the four LS versions required, now had +4.6V, still a bit low.





Part 3, connecting up the count, carry, load & reset lines to the mainboard, not a 100% success, the inputs are functioning, but the display is reading ten times the measured value, example shown of the 20kΩ range with 890Ω on the decade resistor and a leak-A-cell™ D cell was reading 15V instead of 1.5V.





Still to do, check the count, carry, load & reset lines with a DSO at the weekend and compare with the logic analyzer results from another thread, I don't have a working logic analyzer at the moment. 

P.S. I'm, glad I didn't send my gerbers off to JCBPCB, would have wasted my money.

David

[factory]

Extra pic for above.

P.S. why is the quick edit now borked?  It returns to page one without saving changes.

[Vince]

I'm impressed, the last couple of HP VTVM I worked on needed a few caps (some were open) changing, had a worn out choob in one of them too, it had grid leakage (even after the paper cap was changed).

You jinxed it ! Now the needle sometimes gets agitated ! 
It still reads fine, but every other second it gets agitated and jumps around, almost always toward full scale, never toward a lower value.
Yeah... of course some cap somewhere needs replacing for sure...

I would leave it as is, unless you had equipment to check all ranges

I could use my old '70s Philips analog sig gen. it can go up to 20Vpp and has a 60dB attenuator, so I could go much higher and lower than with the HP.
Of course the Philips doesn't have an accurate or calibrated amplitude indication... but who cares, I could just measure its output with my Metrix MX56C TRMS DMM, it's good for 100kHz and super accurate, so would do it.

The highest range of the VTVM is 300Vrms.... so I guess I could simply measure MAINS with it ?! 
That idea gives me the creeps... but if we look at it from a cold, objective perspective.... mains is 240Vrms, so well within range 
Then I could cobble together a voltage divider to lower mains voltage so I could then test the 100V range.
Yeah.... where there is a will there is a way ! 

Did you try it with any non sine waveforms.

No I didn't...but now I have, you made me put it back on the bench ! 

First I tested the HP sig gen itself to make sure it actually maintains a constant RMS value if I switch waveforms....
Measured it with my MX56C DMM.  I set the HP to 500mV so I can get 1Vrms into the 10Meg DMM.
DMM reads 1.01Vrms. Then I switched to square and triangle, and phew, the rms voltage does remain constant.. almost. It does increase a bit, to maybe 1.013 or 1.014.... so not very significant. Good enough for Vince.

So I then fed that into the VTVM... and when I change waveform the needle, once stabilized, reliably ends up exactly where it was in sine wave at the beginning.  Spot on. 

Let us know if you don't get any takers locally.

OK will do. Will let it sit for 3 months or so, it's usually enough to sell, if there is a buyer. If there is zero contact / interest within 3 months, it's unlikely there ever will be. I won't be greedy and will advertise it at 50 Euros straight away, not some silly 100 or 150 like others on Leboncoin would...

My guess of the on the next TE is the Philips PM2440, which will either be full of good film caps, or if it's old enough, full of tar covered paper crap. 

You almost got that right, congratulations ! 

I did fancy picking that one, as I quite like it and was curious to see how it's made inside, and if it worked... but then I changed plan and went for the BEEEEP instead ! 

Stay tuned....

I started playing with it yesterday, will try spending 30 minutes on it again this evening before going to bed....I am already feeling tired.
Most likely I will be able to post about it tomorrow evening.

[factory]

Just found this HP protoytpe plug-in for the the 180 series, too bad the seller hates overseas. 
https://www.ebay.com/itm/134368000692

Probably totally useless without documentation, also seems to have a couple of empty transistor sockets.

David

[wkb]

I think I never posted my "for now it seems to work" repair of my pre-historic Systron Donner SA?

It is more, IMHO, suitable for staring at signals than for actual measurements but ok, it has well passed its retirement age by now.

Wilko

[Robert763]

image borked. try puiing it as the second image