Test Equipment Anonymous (TEA) group therapy thread

[Robert763]

I nearly bid in the inductors 

My ex MOD AVO 8 MkV turned up. Packing was very poor. itn the carry case but just a thin layer of cardboard around that. No padding whatsoever 
But it seems to have survived. Within spec on all ranges.
Generally ebay uk has no worthwhile TE at the moment. Either rubbish or grossly overpriced.
And another  "pulled from a working environment" is meaningless.  A skip is a working environment as is a scrapyard 

Robert.

[AVGresponding]

Sorry AVG, sods law the only two bidders interested in the Data Precision DMM, were us TEA addicts.

  Such is life. At least I know it went to a good home, and not some douchey clock-builder.

Even auction items sometimes go a bit silly in price, such as this HP DVM. 


David

No shit! It's incomprehensible to me, but two people bid nearly £60 for this old piece of crap:  https://www.ebay.co.uk/itm/325561595675

[tggzzz]

No shit! It's incomprehensible to me, but two people bid nearly £60 for this old piece of crap:  https://www.ebay.co.uk/itm/325561595675

Looks like a good example of the price being determined by the second/losing bidder. Personally, with rare/old kit I don't think auctions are the right way to go. Dutch auctions on fleabay seem more likely to get an indecent price.

But hey! I've got a Sinclair SC110 scope that works as well as anything Sinclair made, plus the digitising front end for it. I really ought to make up a battery compartment lid for it, and flog it for silly money.

[Specmaster]

Hmm, thats a point, I haven't seen a dutch auction on eBay for yonks, do they still have them I wonder?

[duckduck]

And another  "pulled from a working environment" is meaningless.  A skip is a working environment as is a scrapyard 

I work in IT. Every time I read that "pulled from a working environment", I just think of the closet or the large wheelie-bins where all of the worn-out / broken / replaced network and computer equipment is stored before the junk-buyer comes round to collect it. I've worked at places with tight controls on retired gear, and I've worked at places with effectively no controls (employees pick through the bins and take stuff home). The stuff in that bin may work fine, or it may have been used as a spares donor, or it may sizzle and make the overhead lights dim as soon as it's connected to the mains. I've also seen the other side, working for the people that made those junk-buys and you get nice new stuff that doesn't work, sad old stuff that is on its last leg, and everything in between.

I have purchased several items listed as "Used" on ePay that are DOA and the sellers worked with me toward an equitable outcome, but it can take a lot of time and hassle and luck to get there.

[AVGresponding]

@Terra Operative, this question would seem to be right up your street:  https://www.eevblog.com/forum/testgear/tektronix-knobbutton-panel-interchange/

[tggzzz]

Hmm, thats a point, I haven't seen a dutch auction on eBay for yonks, do they still have them I wonder?

Informally, manually. Probably tied to the period of  80% off variable fees i.e. relist every fortnight

[m k]

3rd of May came and proto boards are not what I ordered.
And holes are hardly inside pads.

So nagging on principle it is then, irritating.

[URI]

Oh, dear!

Catching up I just came across the painful discussions all around this TEA thread and the leave of many regulars that I will miss. Not all, indeed.
I know I'm just 3/4 of a year late but I feel a bit depressed currently about this thread not being the same I left when preparing the house and moving into it.

Honestly, this thread was from the beginning the connection to others suffering from TEA, too and I got so used to it, it really helped me and I still need help.   

I'll share rebuilding my bench and also will share impressions of my second HP 5370B..

One last question and then I'll leave this topic: Is the discord meeting every saturday still alive?

[factory]

:-+Very good deal on the standard inductors, they works with HP 4342A Q meter, but Boonton Q meters will give different reading from the label.

I was aware they were later than the Boonton/HP Q meters, also the eight I won are the lower frequency ones (number 5 & 10 are missing), the last owner didn't have a HP Q meter either, he had an Advance Q meter & Marconi TF868B bridge to measure the inductance, I wonder if the page of measurements is still with the HP inductor, it wasn't shown in the ePay pictures. 

The older Q meters are just as hard to find as the 4342A in the UK, HP memory project hints the Boonton 260A was quickly obsolete once it had been rebranded by HP, due to the 4342A.
https://www.hpmemoryproject.org/wb_pages/wall_b_page_09.htm

There are a few other Boonton Q meters with different frequency ranges, 160A (50kHz to 75MHz) 170A (30MHz to 200MHz) 260A (50kHz to 50MHz) 280A (210MHz to 610MHz) etc.
There are some type 103A inductors for the 160A/260A listed in this manual, along with type 513/518 Q standards, no idea how they compare.
http://hparchive.com/Boonton/Boonton-Manual-160A-260A.pdf

David

[tautech]

Oh, dear!

Catching up I just came across the painful discussions all around this TEA thread and the leave of many regulars that I will miss. Not all, indeed.
I know I'm just 3/4 of a year late but I feel a bit depressed currently about this thread not being the same I left when preparing the house and moving into it.

Honestly, this thread was from the beginning the connection to others suffering from TEA, too and I got so used to it, it really helped me and I still need help.   

I'll share rebuilding my bench and also will share impressions of my second HP 5370B..

One last question and then I'll leave this topic: Is the discord meeting every saturday still alive?

Discord is alive and well and busier than ever !

Bitseeker arranged a new home for us here:
https://teanonymous.com/f1/index.php

[vk6zgo]

Oh, dear!

Catching up I just came across the painful discussions all around this TEA thread and the leave of many regulars that I will miss. Not all, indeed.
I know I'm just 3/4 of a year late but I feel a bit depressed currently about this thread not being the same I left when preparing the house and moving into it.

Honestly, this thread was from the beginning the connection to others suffering from TEA, too and I got so used to it, it really helped me and I still need help.   

I'll share rebuilding my bench and also will share impressions of my second HP 5370B..

One last question and then I'll leave this topic: Is the discord meeting every saturday still alive?

Discord is pretty much non-stop, & has taken over most of the discussions.

[tggzzz]

I didn't realise Avo made a scope...

https://www.the-saleroom.com/en-gb/auction-catalogues/richard-winterton-auctioneers/catalogue-id-srric10345/lot-9ebf4587-acc1-43f5-ad8d-afc1009f301d

[Andrew_Debbie]

No shit! It's incomprehensible to me, but two people bid nearly £60 for this old piece of crap: 

Sentimental value perhaps? Sinclair collector?  I've got some Dana and Racal Dana gear because my first technician job was next door to Dana. 

 £58+£6.85 for a 31/2 digit meter powered by 6 C cells    .  That kind of money buys a brand new BM235 with local warranty support or a 22,000 count UT61E from AliExpress.

[Robert763]

I didn't realise Avo made a scope...

https://www.the-saleroom.com/en-gb/auction-catalogues/richard-winterton-auctioneers/catalogue-id-srric10345/lot-9ebf4587-acc1-43f5-ad8d-afc1009f301d

They didn't. That's a rebranded Scopex 4D10. Not even a change of colour....

[factory]

Spent quite a bit of time over the weekend & all day yesterday soldering some of the SMT boards for my HP counters, just left the through hole parts for when they are needed, still need to verify they work in the higher speed display decades and test the gated function in one of the timebase boards. The 74LS90 that I fitted upside down was sacrificed and replaced with another. 





Today I had a look at the early design HP 5326B I have, that has never worked properly, it had a fault where it didn't reset the count to zero and just added the next count, the DVM part was also dead.
This turned out to be a really easy fix, it was narrowed down to the function control assembly, this is two boards joined together with HP's custom square section connector, I could get it working intermittently by tapping this board, cleaning the connector & board has restored normal operation. This isn't the first time I've had trouble with these square section connectors. 





Quick check with the old battery from the Tek 2445/2465 scopes and HP 3310A function generator.





David

[HenryFeng]

103A are working coils, that are labeled with L, C, Q and frequency range. 518A are Q standards, they are labeled with Q, C and 3 frequency points, 513 is Q standard also, it labeled with L, C, Q and frequency points. 164xx are labeled with L, C and frequency range, only specified Q limit is 300.

:-+Very good deal on the standard inductors, they works with HP 4342A Q meter, but Boonton Q meters will give different reading from the label.

I was aware they were later than the Boonton/HP Q meters, also the eight I won are the lower frequency ones (number 5 & 10 are missing), the last owner didn't have a HP Q meter either, he had an Advance Q meter & Marconi TF868B bridge to measure the inductance, I wonder if the page of measurements is still with the HP inductor, it wasn't shown in the ePay pictures. 

The older Q meters are just as hard to find as the 4342A in the UK, HP memory project hints the Boonton 260A was quickly obsolete once it had been rebranded by HP, due to the 4342A.
https://www.hpmemoryproject.org/wb_pages/wall_b_page_09.htm

There are a few other Boonton Q meters with different frequency ranges, 160A (50kHz to 75MHz) 170A (30MHz to 200MHz) 260A (50kHz to 50MHz) 280A (210MHz to 610MHz) etc.
There are some type 103A inductors for the 160A/260A listed in this manual, along with type 513/518 Q standards, no idea how they compare.
http://hparchive.com/Boonton/Boonton-Manual-160A-260A.pdf

David

[Ice-Tea]

I normally don't do painting but, well...



So, I probably broke every rule in the "spraypainting for dummies" book. And got this:



won't win every prizes but it ticks the 'better than before box'. I wasn't expecting the masking tape to damage the inlays, though... That was kinda unpleasant. Also unpleasant: one line of the keyboard ain't home. Need to check that, too 

[bsfeechannel]

Wanted to pass this along. I nearly got scammed with this Type G plug-in project. Something to watch out for on future TE purchases.

https://teanonymous.com/f1/viewtopic.php?t=125

Man, I need to master your asset tag removal technique. I have a bunch of old instruments full of them, most glued with epoxy. 🤮

[factory]

It depends, I prefer to keep some of the history and older asset/owner tags are part of that, but modern cal, PAT, safety test, auction stickers can go straight to the trash can.

Example below of the 5327B I've been working on this afternoon, the labels on the back indicate it was part of one of HP's automated test setups.





David

[m k]

This isn't the first time I've had trouble with these square section connectors.

From small picture I thought the connector had multiple rows.
Maybe it's an early prototype.

[factory]

It's not a prototype, it's the original late 1960s design.
They had to shuffle the innards about, when the 10544 series oven oscillator became available in the 1970s. They clearly took the opportunity to redesign the two function control boards, into one multilayer board and eliminated the square connector.
They are many other changes, hence the reference to a different manual for the older ones, I need to find the older one.


I'll try and get some better pictures of the square connector when I get a chance, they can have boards sandwiched together, or boards at right angles and the fourth side can be either soldered to a board, or have solder points for wiring.
I'm sure there is a nice write-up in one of the HP journals, just haven't come across it yet, if it exists. 
They are used in the 5326/7 counters, 8640B signal gen for the counter (again), the 5321 k21-lock.

The second HP 5327B counter (originally missing DVM control board) worked when I received it, but quickly stopped counting while I was checking the counter functions, this again turned out to be an easy repair, which was narrowed down to the function control board, took me ages to find the appropriate extender, then I noticed one of the ICs in sockets looked a bit loose & the pins a little bent, I took it out straightened the pins & refitted it, I also reseated the other two socketed ICs, this cured the no count fault.



The next problem was failed blanking on the second number readout bulb, the 7 was lit when it should be blanked, I took the set of decade counter, latch & display decoder ICs out and fitted sockets for my new 1820-0092, 1820-0116* & 1820-0119 boards, this fixed it, I run out of time to confirm if the original display decoder was to blame.
But this did allow me to test the new boards in the higher speed position, they all seem good.



*Note: the new 1820-0116 board does not have the gated (recorder) outputs yet, I found this shown in the 8443A manual, something to add to rev.B. 

One of the new 1820-0413 boards was tested in the timebase board too, this was required to make sure the gated output was working, the new DVM control board also works fine. 



Last thing to test/repair, are the 500MHz inputs of both 5327B counters, need to find/buy the top & bottom covers to complete the second 5327B too.



David

[m k]

They are many other changes, hence the reference to a different manual for the older ones, I need to find the older one.

I found a list from early '70s with many low 60k numbers, possibly the same list from where you found those chip drawings, 15 and 24 were not there.
15 has that extended edge so I guess it should be a complete part.

[TERRA Operative]

Calling all people with a National Instruments ISA GPIB-PCII/IIA GPIB card and a chip reader!

Seems my faulty card is maybe, possibly, likely due to a failed GAL16V8D. I think if someone could read out theirs and give me the file, I might be able to reprogram this chip, or a new one and maybe get this card working again...
Mine is a Rev 2.1 board with the big NAT4882D chip, not the VLSI chip. Unfortunately my other cards aren't the same revision, so the GAL image won't work..

[m k]

My guess is that NI and VLSI chips are quite same.

Can you open up your troubleshooting a bit?
Maybe a dip is not dipping correctly.

One version of NI and VLSI models seem to have equal layouts and only 3 tracks to controller chip.
Maybe it's a simple Chip Select thingy that can be guessed and hardwired.

Some cases IRQ and DMA are not mandatory.
Maybe different test program can see it differently.