Test Equipment Anonymous (TEA) group therapy thread

[atokhy]

At the moment there are ADCMT 7461A's and ADCMT 7351A's going for auction on Ebay from a US seller and the auction isn't as crowded so I should get better deals here.  These must be from a Japanese manufacturer in the US getting rid of their old test equipment (Toyota maybe). The idle power consumption on the 7461A is pretty low according to my kill-a-watt (about 13W).  This might be the case with the older Advantest R6581E-DC 7 1/2 digit models which I am hesitating on which could act as a calibration source.  The 8 1/2 digit advantest is beyond my budget though if I settle for 7 1/2 as my highest precision multimeter.  Idle power consumption may not be as much of a big deal for me as I have already installed a 9kW solar power system for this house so I should be able to power quite a few toys  .

The 7461A is a great choice. It's similar to 34401A/K2000 in specs and environmental characteristics (silent/fanless/sealed), and it's slightly more modern with PC-USB and internal logging/statistics capability. It also allows for 10 second integration, which is highly unusual. It uses a less conventional voltage reference if it's the same as the AD7461A. I think along with USB drivers they provide some kind of spreadsheet with VB/macros to sample directly into Excel, I don't have MS Office license so I haven't tried it. I have used the GPIB interface.

The R6871E is also silent and fanless, but not sealed. It has a bright green LED display that might outlast humanity and real banana plugs, but I'm not sure you are missing out on much. It does have a 1 Gigohm resistance range, 1 MHz ACV, and a usable* extra digit, but it's also quite bulky. They made the R6561 as well, which was optimized for smaller signals/stability/noise and only measured voltage/resistance. The R6581 was the 8.5 digit, I don't have any experience with it. ADCMT might have more modern offerings as well, I'm not familiar with them.

I wouldn't count on finding schematics for any of these, maybe the older Takeda Riken meters they were based on.

Other obscure Japanese meters would be the 6.5d Yokogawa 7561/7562/7563 with bright red LED displays, the more modern 6.5d Yokogawa DM7560, and the 7.5d Hioki DM7275/6.

So far I have not purchased the R6871E-DC yet.  It can measure up to 7 1/2 digits but they are very affordable compared to other 7 1/2 digit meters on Ebay (which also have no schematics).  The next level up are 8 1/2 digit metrology grade meters which are currently beyond my budget.  I do not have sufficient bench space for these.

EDIT: My second multimeter will be a DAQ, the Agilent 34970A, with a 34902A 16 channel multiplexer and a 34904A 4x8 matrix switch module, thanks to one of the suggestions here on performing simultaneous measurements.  It comes with RS232 which is good enough for me.

I could instead, not buy the R6871E-DC, and instead get buy a Advantest 6142 voltage/current source for about the same cost.  I want an accurate voltage/current standard that I could calibrate everything against.  It can also double as a 4-quadrant power supply for battery charge/discharge IC testing/curve tracing/etc.

However the 6142 is GBIP only, and it lacks any source-measurement functionality.  I could spend twice as much and get a newer, ADCMT 6241A source/measure unit (which provides the same feature set as the older Advantest 6142, has source/measure capability and comes with USB).  It would set me back $1000 but it would take little to no space, and it would keep the bench tidy.  As far as I'm aware, $1000 is cheap for an SMU, especially since the budget branded ones start at about $2500 new.  I'm also seriously considering building out the DIY-SMU, now that there are parts available.  I am a bit reluctant though, since there are floating high voltages in it.  I need to see if anyone has worked on a modification that does +/- 30V.  Decisions, decisions...

As for the ADCMT 7461A, it's been running for about a week measuring an AD584 (~25ppm voltage source) and I only notice the last digit fluctuating due to the slight temperature changes in the basement.  I have already figured out how most of the features work on the ADCMT 7461A, and I'm going to see if I can get a serial console (SCPI) connection to it.  I have also tested both multi meter channels and I can take 2 simultaneous measurements.  I will see if I could record/log measurements from both channel A and channel B with SCPI commands, or whether I can measure voltage in channel B, and current in channel A and log this simultaneously, dump it in XLS, and spit out a nice IV chart.  I should be getting my GPP4323-LAN today, which should act as both a source and a load to conduct this new equipment trial run.

I also don't own Microsoft Excel, I plan on dumping data directly into CSV while using MATLAB (or any OSS equivalents) to create plots and graphs.  This will all plug into one of my older Linux PCs with many freely available USB 2.0 slots.

[zepto]

I don't think the 6142 is a 4-quadrant device, but you could use it as a reference and for curve tracing when combined with a meter and some programming. The 6142 is based on the TR6142 which was based on the TR6141. The TR6141 is really interesting because it was a late 1970s PWM voltage/current reference implemented using discrete logic chips. No MCU, FPGAs, CPLDs, or (EE)PROMS, but quite a few counters, (N)AND, (N)OR, and XOR gates! It was even rebadged by an American company, perhaps solely to give it an NSN and allow for federal procurement. Takeda Riken was an early innovator in PWM references, they also made the TR6120. Fluke was maybe less eager to replace their resistors with digital logic. The remote parallel interface on the 6142 is an artifact of the old design and a large part of what made the PWM design so appealing initially.

I believe the R6145, 6146, and 6156 can source and sink. The TR6143 (SMU) is another option that can source and sink 100V/60W, but it is rather large, heavy, and loud.

[Vince]

Oh, my 49th scope... I could not help myself.

10 years ago I bought at TDS 310, defective for 60 Euros, as my first attempt at repairing TE, and because I wanted a TDS300 series scope in my vintage Tek collection, if just out of nostalgia :  I remember at school when we received a brand spanking new TDS 320 IIRC, that was so expensive at the time, that only the teachers were allowed to use it. Ah well...

Anyway, that broken TDS 310 repair didn't go smoothly so I had to call it quit and declare it uneconomically repairable.

Well last week I finally managed to get another cheap one, 60 Euros again, except this time it's a much better one, a TDS 340A. Just received it this evening.



The 310 is the very bottom of the barrel, with 60MHz and 200Ms/s, but the 340A is decent, at 100MHz and 500MS/s. Also, it's got a shit load of I/O at the back : RS-232, VGA, centronics/printer, and GPIB. I am covered...  Better yet, it comes with the floppy drive... which I tried, and believe you me, it actually still works !!  I don't know what's more surprising, the fact that it still works, or that the random 30 year old floppy I put in it, is still good as well ! 
Sadly as of recently, I don't have a floppy drive anymore in my desktop computer. I had to replace the 16 year old motherboard and all that goes on it, meaning I lost the floppy drive port (as well the centronics port, can't use my trusty 28yo LaserJet 6P printer anymore  ).  I will try and get an external USB Floppy drive...



Of course the scope was cheap for a reason : seller said it failed the self test, calibration issue, but the scope can still display traces on both channels just fine. I ran the tests myself to make sure I have current data in the error log, then looked at the log and... well see for yourself : looks like basically the only problem might be just a dead battery in the NVRAM, so the scope lost all cal constants and whatnot.



Indeed it's out of cal : channel 1 shows correct amplitude but channel 2 displays it a bit too large. Also, if I give the scope a square signal, both channels show an awful lot of ringing :



So I need to replace that NVRAM, the battery in it at least, then recalibrate the scope, assuming it's even possible. I guess one needs special S/W that might not be available...

[factory]

I'm guessing the only reason that slim floppy drive works, is that it is a direct drive version and not those crappy belt drive things I gave up on. Some replacement direct drive FDDs cured that issue for me, I noted the Yokogawa at work had the same problem , bits of belt everywhere inside.

I'm not that familiar with those TDS scopes, only one I have (2014) is a little newer, has LCD, four channel and is a lot smaller, no comms options fitted though.

David

[Vince]

Ah yeah direct drive, forgot about this... a nice improvement for sure...

[atokhy]

I don't think the 6142 is a 4-quadrant device, but you could use it as a reference and for curve tracing when combined with a meter and some programming. The 6142 is based on the TR6142 which was based on the TR6141. The TR6141 is really interesting because it was a late 1970s PWM voltage/current reference implemented using discrete logic chips. No MCU, FPGAs, CPLDs, or (EE)PROMS, but quite a few counters, (N)AND, (N)OR, and XOR gates! It was even rebadged by an American company, perhaps solely to give it an NSN and allow for federal procurement. Takeda Riken was an early innovator in PWM references, they also made the TR6120. Fluke was maybe less eager to replace their resistors with digital logic. The remote parallel interface on the 6142 is an artifact of the old design and a large part of what made the PWM design so appealing initially.

I believe the R6145, 6146, and 6156 can source and sink. The TR6143 (SMU) is another option that can source and sink 100V/60W, but it is rather large, heavy, and loud.

Oh I see, it looks like the Advantest R6142/R6144 cannot sink current, it can only source current with +/- voltage.  This would make it a 2-quadrant unit then.  In that case I could get a Agilent 66319B/D instead.  I am mixing up Advantest R6142 and ADCMT 6241A in thinking they're similar...

I have been eyeing the ADCMT 6241A/6251A for quite some time.  I think I could get one for around $950 (this would have been around $1500 a few years ago) with the current Yen/USD exchange rate.  I'm thinking about buying one, and making a video about it.  I see no information online about these.  I found a bunch of broken Advantest equipment from a Japanese used item reseller, I could bulk order some known, broken items and see if I can get it to work.  They appear to do international shipping, but I'll have to ask them how much it would cost.

So far I've found:
1x Advantest 6243 (6 bad buttons) - $270
1x Advantest 7461A (dim VFD) - $125
1x Advantest TR5824A Frequency Counter - $82
1x Advantest 6122 voltage/current source - $118

[TERRA Operative]

Looks like the TDS340A cal just needs a few basic bits of gear and can be done in the scope itself, no extra software needed.

https://w140.com/tekwiki/images/b/b4/070-9435-03.pdf

https://w140.com/tekwiki/wiki/TDS340


Might be worth throwing a Gotek USB floppy emulator in. I put them in my TDS784D and TDS794D scopes and they work great.

[Vince]

Looks like the TDS340A cal just needs a few basic bits of gear and can be done in the scope itself, no extra software needed.

https://w140.com/tekwiki/images/b/b4/070-9435-03.pdf
https://w140.com/tekwiki/wiki/TDS340

Oh great !! 
Had a quick look at the manual, can't find any detailed instructions on how to perform the calibration, but I did spot a quick mention that said one can enable hidden calibration menus by fiddlnig with a jumper on the main board. I guess then one just has to follow the instructions given by the scope itself on the screen...

The Wiki article fails to explain the differences between the 340 and 340A ... maybe there aren't any and it's just marketing...

So, I guess I now need to actively hunt for a levelled sine wave generator ! Preferably not a boat anchor nor full width rack size thing, and preferably well below 500 Euros... any suggestions ?
Would like it to go to 1GHz hopefully, so I can test or calibrate all my scopes but the TDS694C, for a 3+ GHz gen is out of my budget I imagine.

Might be worth throwing a Gotek USB floppy emulator in. I put them in my TDS784D and TDS794D scopes and they work great.

Oh no I prefer to keep the scope original in this regard ! 
It preserves the vintage charm, and consistency, of the scope.
It love all floppies, brings me back 35+ years back when I was little, makes me feel younger ! 
It's not like I were using the scope 7 hours a day every day, doing tens or hundreds of screen captures all day long... so I don't care if I have to wait a few seconds for the scope to write to the floppy.

I hope you kept the original floppy drive of that 784D ? Please put it back in !
How much of a discount do I get if I buy it with the original floppy drive ?! 

[factory]

So, I guess I now need to actively hunt for a level sine wave generator ! Preferably not a boat anchor nor full width rack size thing, and preferably well below 500 Euros... any suggestions ?
Would like it to go to 1GHz hopefully, so I can test or calibrate all my scopes but the TDS694C, for a 3+ GHz gen is out of my budget I imagine.

The older Tek cal fixtures had constant amplitude signal generators, no idea why they changed to calling them levelled sine wave generators. 

The one I have does up 65 to 500MHz, mine is the 067-0532-00, but there is also slightly newer looking 01 version.
https://w140.com/tekwiki/wiki/067-0532-00

They didn't quite go up to the 1GHz, but the other one 067-0650-00, does 220 to 900MHz.
https://w140.com/tekwiki/wiki/067-0650-00

David

[atokhy]

Looks like I won't be able to get that old Advantest gear.  Buying equipment from Japan directly is providing to be difficult as there are export controls over even the most basic lab bench equipment.  I asked before I ordered anything and they pointed at this law.

https://www.japaneselawtranslation.go.jp/en/laws/view/3389

[Hydron]

Hmm, I wonder if it applies if you're leaving Japan with TE in your luggage (I see there's stuff in that law about "occupational tools" but I have no hope of actually understanding the legalese gibberish properly).

Might be there for work later this year and something like a Advantest R6243 would be mighty temping, especially if they are available for $270 (where did you see that sort of price?)

[TERRA Operative]

Looks like I won't be able to get that old Advantest gear.  Buying equipment from Japan directly is providing to be difficult as there are export controls over even the most basic lab bench equipment.  I asked before I ordered anything and they pointed at this law.

https://www.japaneselawtranslation.go.jp/en/laws/view/3389

What seller are you dealing with? I know most just won't post international, those that do can be hit or miss, and at lest one seller makes even local buyers pinkie promise not to send the gear they buy international, even for the most basic BNC cable....

I ignore all of that crap. As long as there are no obvious batteries (that's all that Japan Post care about), it's not using current encryption or a 50GHz scope, and it's not going to Iran or North Korea, there's no real problem sending stuff.


Ive come in and out of Japan with test gear. Besides a 'what's that!?' out of curiosity (because it's not yet another laptop or Gameboy) no-one gave a single care what it was.


PM me, maybe we can work something out.

Looks like the TDS340A cal just needs a few basic bits of gear and can be done in the scope itself, no extra software needed.

https://w140.com/tekwiki/images/b/b4/070-9435-03.pdf
https://w140.com/tekwiki/wiki/TDS340

Oh great !! 
Had a quick look at the manual, can't find any detailed instructions on how to perform the calibration, but I did spot a quick mention that said one can enable hidden calibration menus by fiddlnig with a jumper on the main board. I guess then one just has to follow the instructions given by the scope itself on the screen...

The Wiki article fails to explain the differences between the 340 and 340A ... maybe there aren't any and it's just marketing...

So, I guess I now need to actively hunt for a levelled sine wave generator ! Preferably not a boat anchor nor full width rack size thing, and preferably well below 500 Euros... any suggestions ?
Would like it to go to 1GHz hopefully, so I can test or calibrate all my scopes but the TDS694C, for a 3+ GHz gen is out of my budget I imagine.

Might be worth throwing a Gotek USB floppy emulator in. I put them in my TDS784D and TDS794D scopes and they work great.

Oh no I prefer to keep the scope original in this regard ! 
It preserves the vintage charm, and consistency, of the scope.
It love all floppies, brings me back 35+ years back when I was little, makes me feel younger ! 
It's not like I were using the scope 7 hours a day every day, doing tens or hundreds of screen captures all day long... so I don't care if I have to wait a few seconds for the scope to write to the floppy.

I hope you kept the original floppy drive of that 784D ? Please put it back in !
How much of a discount do I get if I buy it with the original floppy drive ?! 

Section 5 on page 74, it runs through the entire adjustment procedure including diagrams.


Don't worry, I have a second TDS784D here that will remain a floppy drive virgin. I just gotta get new NVRAM's installed (but I'm currently waiting for the Chinese New Year to finish...), and once it's working then you can give me your shipping address.

My TDS784D/TDS794D will likely get to see some paid production time soon, so converting the FDD to USB makes for a smoother work experience.

[atokhy]

Looks like I won't be able to get that old Advantest gear.  Buying equipment from Japan directly is providing to be difficult as there are export controls over even the most basic lab bench equipment.  I asked before I ordered anything and they pointed at this law.

https://www.japaneselawtranslation.go.jp/en/laws/view/3389

What seller are you dealing with? I know most just won't post international, those that do can be hit or miss, and at lest one seller makes even local buyers pinkie promise not to send the gear they buy international, even for the most basic BNC cable....

I ignore all of that crap. As long as there are no obvious batteries (that's all that Japan Post care about), it's not using current encryption or a 50GHz scope, and it's not going to Iran or North Korea, there's no real problem sending stuff.


Ive come in and out of Japan with test gear. Besides a 'what's that!?' out of curiosity (because it's not yet another laptop or Gameboy) no-one gave a single care what it was.


PM me, maybe we can work something out.

I was trying to use the buyee.jp service, a proxy service for buying from Japanese auction sites.  It provides a translation service so I am able to mostly use it.  The stuff I was trying to buy is partially broken equipment anyway.

[factory]

The past year has given, in memory of himself, an Englishman in a box condition.
I found the technical manual for it, but I did not find the operating manual. Does anyone have a scan?

Yes it seems all manuals on the web are the technical, there are 3 separate scans on the web archive, one of which is the Guildline 9575/9576 branded version of the Solartron Schlumberger 7055/7065.

According to my notes I have an original ops manual, but didn't note which part it was (I think it's in storage, but won't have time to go there this weekend), guess it's never going to be any use to me, seeing as MJ keeps buying up the affordable parts ones & destroying them.
Two spares/repair 7065 in overall good condition, were sold for approx £124 in Dec; https://www.ebay.co.uk/itm/395998305213 I spent too much in Dec & couldn't bid.
Some boards appeared on feeBay a day or two ago.   :'(

David

Part 1 of the operating manual for the Solartron 7055/7065 has been scanned and is now available to download from Bama:

https://bama.edebris.com/manuals/solartron/7065/

I've not got the other two parts, maybe others have.

David

[Cyclotron]

I have a new girlfriend named Madonna. You should be able to tell from her photos how she got that name.
I've gotten her all cleaned up and her numbers are spot on.  But how could they not be? "This one goes to eleven."

[tggzzz]

I have a new girlfriend named Madonna. You should be able to tell from her photos how she got that name.
I've gotten her all cleaned up and her numbers are spot on.  But how could they not be? "This one goes to eleven."

Pictures can never indicate the almost pornographic way the dials move and clack.

[Cyclotron]

Pictures can never indicate the almost pornographic way the dials move and clack.

I see you've had your had your hands on a madonna. 

My wife came by while I was cleaning and testing it. She said, "I'm jealous now," laughed....  Then she got a bit ticked when I said, "You should be."

[tggzzz]

Pictures can never indicate the almost pornographic way the dials move and clack.

I see you've had your had your hands on a madonna. 

Two actually, one for each hand. 

One a 1kohm dekapot, the other a 121.1ohm dekastat.

[timeandfrequency]

Pictures can never indicate the almost pornographic way the dials move and clack.

I see you've had your had your hands on a madonna. 

Two actually, one for each hand. 

One a 1kohm dekapot, the other a 121.1ohm dekastat.

You are takling about a precision device

[tggzzz]

Pictures can never indicate the almost pornographic way the dials move and clack.

I see you've had your had your hands on a madonna. 

Two actually, one for each hand. 

One a 1kohm dekapot, the other a 121.1ohm dekastat.

You are takling about a precision device

Here's a roundabout near a regional shopping centre, created not too long after that "concept" was widely publicised:
https://www.google.com/maps/@51.5240816,-2.6041261,27a,35y,3.25h,76.18t/data=!3m1!1e3?entry=ttu&g_ep=EgoyMDI1MDEyOS4xIKXMDSoASAFQAw%3D%3D


To complement it, just down the road is:
https://www.google.com/maps/@51.5229488,-2.5909584,71a,35y,214.92h,59.52t/data=


Followed by
https://www.google.com/maps/@51.5262154,-2.5874815,37a,35y,211.05h,72.34t/data=


All three are best seen in gurgle 3d view, rotating the picture to get the full effect.

[Robert763]

Nice,
I have a DB877 a DB655 two Dekatrans and a Dekavider.
Have you checked the specification of the DB877? It's a 0.01% device, 8 decades and it's not 2 foot long.
About the best decade box you can get.

Technically it's not a decade box though because: A. Each dial goes from 0 - 11 and B. It's a R / 2R network so only 6 resistors per section.
They cost thousands of dollars when new.

Robert.

[tggzzz]

Nice,
I have a DB877 a DB655 two Dekatrans and a Dekavider.
Have you checked the specification of the DB877? It's a 0.01% device, 8 decades and it's not 2 foot long.
About the best decade box you can get.

Technically it's not a decade box though because: A. Each dial goes from 0 - 11 and B. It's a R / 2R network so only 6 resistors per section.
They cost thousands of dollars when new.

Sweet.

What's the "B" setting? I don't see any reference to that in the db877 manual.

[factory]

You've misread the post, it's point A and point B, not part of the decade box.

David

[tggzzz]

You've misread the post, it's point A and point B, not part of the decade box.

Ah. Eats shoots and leaves

Sexy box, though.

[eevcandies]

Finally...got a 200MHz 4 chan TPS2024B Oscilloscope in perfect shape including 2 perfect batteries for $550.  Will use occasionally on high voltage work.  The individually gnd isolated channels will be a welcome treat. 

Two plastic BNC insulator shields were cracked, but don't affect performance (watch your fingers).  I gonna 3D print some  (or buy an official Tek set for $50....must be 10cents worth of plastic!!!)...they mount in about 30 seconds, the plastic bnc cover snaps off to reveal a nut (at first thought you needed to take scope apart to access, NOPE!).  No one else makes these replaceable BNC insulators--they were apparently patented by Tek around 2004.  This has software rev 11.09 from 2012.  Does anyone know if that is REALLY the latest (shows that on Tek site) ? 

There is apparently a snap on scope cover, don't have, but may look for one.  If the power key application pak was cheap would get that too.