Test Equipment Anonymous (TEA) group therapy thread

[mansaxel]

5440 update:

I have (had) a trace!

The scope is definitely not sick in simple ways. The trick to coax a trace out of it was to put it in single sweep.    Then it works. Sometimes.  Somehow, I think I should clean out the time base switch and the trigger selection switches with lots of IPA or something, and then go forward from there.  It seems almost like that most things that actually are needed likely work, but that signals don't get where they should.

Edited to clarify: The scope sweeps in "single sweep mode". That's what I mean "with signals don't get where they should. " ... 

5245L update:

IEC inlets arrived. Seller had forgot to ship. Once they remembered, it was quick. Now, I'll go forth with that too.

Meinberg GPSDO update:

Vendor suspects TXCO. I'll make a test of the TXCO against another, known good one, and make my dispositions according to results obtained from that.

[tggzzz]

That’s definitely the best HP aesthetic era. The 606 sig gen was my favourite from around there. Would love to get my hands on one.

https://www.hpmemoryproject.org/timeline/art_fong/hp606_01.htm


Also random really good and still really applicable video. Wish they made stuff like this now rather than the YouTube trash you get these days:

That's because creating distributing and showing such materials was difficult and expensive - so people put thought into the content, and compressed it to remove extraneous trivia. Much the same can be said about books, including fiction and software shovelware.

I still direct people to the Pace soldering videos, since they clearly show what you should and shouldn't do https://www.youtube.com/playlist?list=PL926EC0F1F93C1837

[med6753]

5440 update:

I have (had) a trace!

The scope is definitely not sick in simple ways. The trick to coax a trace out of it was to put it in single sweep.    Then it works. Sometimes.  Somehow, I think I should clean out the time base switch and the trigger selection switches with lots of IPA or something, and then go forward from there.  It seems almost like that most things that actually are needed likely work, but that signals don't get where they should.

Edited to clarify: The scope sweeps in "single sweep mode". That's what I mean "with signals don't get where they should. " ... 

Make sure the trigger is set to "Auto" which should make the sweep free run. Hang a probe at the input of the horizontal amp. There should be a sweep waveform. If not, work back from there.

[tggzzz]

Since only pictures are believed, here are some of the two 1960s Solatron DVM. Summary: remarkably good.

The 1420.2 does have one nasty feature: when the count is too low it presumes the polarity is wrong and flips relays to invert the input. That's a problem when doing the tweaks to set the zero voltage and (short term only) zero input current, since if the trimpots are too far out it sits there oscillating and/or showing both 2 and 1 in the most significant digit.

The first picture shows something completely unexpected. The DVMs use an ~80V-82V neon "valve" as a voltage reference, which isn't too accurate. To get around that they contain an unsaturated weston standard cell, and you tweak the gain so it shows 1.019V. The small one is clearly buggered, but the 1420's isn't - which is remarkable given the expected life is 7-14 years. No, I can't measure it directly since it is buried deep inside where I can't access it without too much disassembly.

I haven't seen a nixie indicating ACvolts in that rather nice way.

[Specmaster]

Well, that is a promising start, you can never be sure of what you are going to find when the seller does not show photos of them powered. So far you have an excellent score there, well worth the trip to collect them. Nixies are sought after in meters these days.

[Zucca]

Futch...
mnem
 

mnem
*toddles off to ded*

question is if your heart has only one or more cracks now.

[tggzzz]

Well, that is a promising start, you can never be sure of what you are going to find when the seller does not show photos of them powered. So far you have an excellent score there, well worth the trip to collect them. Nixies are sought after in meters these days.

Probably a promising finish too. I can't even find the weston standard cell in the schematics!

I haven't found a manual for the True RMS AC Unit, and I'm not sure I can be bothered to randomly twiddle pots without knowing what they do.

I've already flipped one nixie DVM and I'll probably flip these, leaving me only a Fluke 8300A

[mnementh]

Very loooooong (but also very rewarding) day today - one that had been in the making for at least three years now..  Several years ago I met a gentleman at a swap meet who, when he learned I collect old test gear and have a special affinity for nixie counters, told me he had a pair of old 524s in his basement that he wanted to give me.  I repeatedly offered to pay him something, anything for them, but he refused, just wanting them to go to a good home.  Between work travel and weather, the meetup never happened that first year, but we kept in touch.  Planned something after my early 2020 trip out west, but then of course the Coof hit and put the kibosh on everything for 2020 and 2021.  After things dried out this spring he was finally able to get them out of his basement and loaded into his car, so today I made a 330 mile (~530 km) round trip up to New Hampshire and retrieved them.

524B:      524C:      Model 64 DVM      -Pat

Awesome score, Pat. We look forwards to lots of tired iron pr0n pics, as we all know you do so very well! 

mnem
*raises a glass to fellow TEAs who are gone but not forgotten*

[Cerebus]

There is no such thing as too many oscilloscopes.

That's what I USED to think... but I have now 40/45 scopes and I am starting to change my mind.... lack of storage space mainly.

Then you need to buy a lot more storage scopes

Oowwww! That was too painful for just a groan.

Please report to the back of the bike sheds for your midday humour correctional kicking. Your school bullies for today are Paul "glass jaw hardman" Harding and Ian "give him the canteen lunch menu at breakfast and he might have it all figured out by lunchtime" Quick.

[bd139]

Yes you were right... but that Agilent still looks effing ugly to me, plus it was yellowed and had broken or missing CRT  bezel keys, no thanks.

Zero regret for not buying it, but very happy I bought that beautiful, lovely, Gorgeous proper original HP one instead.

A THOUSAND LASHES WITH A WET NOODLE! 

Haven't you learned where you are yet, Vince...? The only correct answer is "Of course, I want BOTH!"

mnem
There is no such thing as too many oscilloscopes.

That's what I USED to think... but I have now 40/45 scopes and I am starting to change my mind.... lack of storage space mainly.

I want a few more scope models or brands I have not yet, sure but.... I have now decided that every new scope will  only be allowed if I get rid of an existing one, constant sum.
IOW I am getting more and more critical about my TE. I don't just buy the first vaguely interesting thing. I need to really want it.
I also try to diversify my TE to other types of TE than just scopes.. so for every new TE that comes in, a scope must go in the process.

I am trying to become half reasonable in my TE delirium...not saying it's easy, but I am trying....

I've had more than 45 scopes. But never at the same time. That's the trick 

[Cerebus]

33.5 ºC (93 frankenstein) in the shade outside here at the moment. I ought to go out and wash the (filthy) car, but that ain't happening, and I've got minced beef in the fridge that has to be cooked today. Cook? In this weather? Better go and get it started; at least it means tacos for tea.

That was the grumpy old man weather report. We now return you to your normal programming...

[bd139]

I'm getting some poor bastard to deliver me a pizza today 

[mnementh]

Futch...

mnem
 

   

Oh look a cracked front panel. Seen that before      Why the fuck did they use FR2 for those panels I don't know 

Edit: here's a picture of what happens if the right bit of the panel goes open circuit:      diode to deadode transition...

   

Fortunately it's a pretty simple fix in most cases; this isn't my first rodeo. Remember too, that mine survived being smashed all to fuck in somebody's WEEE-Cycle bin without fault, so they are in fact pretty durable nonetheless. That damage was caused by the BumbleButt Incident after I fixed it up. 

Besides... the real design flaw is not the cheap Paxolin PCB; it's obviously more than adequate for this particular task, as we have how many of them at 20+ years old now and still working after a basic cleaning. Yes, I'd prefer FR4, sure... but the flip side of the "flaw" is we who know how to fix can make great deals on bust-ass 546xxx, like this 54600A I'm working on now for $30.

   

THIS is the real design flaw: That thin piece of steel butted right up against that PCB. Same exact damage in the same exact place on all 3 of these that I've fixed, and as soon as you look at it, quite obvious that it is what made your short-circuit.

It should've never gotten past pre-production vetting.

mnem
 

[mnementh]

Yes you were right... but that Agilent still looks effing ugly to me, plus it was yellowed and had broken or missing CRT  bezel keys, no thanks.

Zero regret for not buying it, but very happy I bought that beautiful, lovely, Gorgeous proper original HP one instead.

A THOUSAND LASHES WITH A WET NOODLE! 

Haven't you learned where you are yet, Vince...? The only correct answer is "Of course, I want BOTH!"

mnem
There is no such thing as too many oscilloscopes.

That's what I USED to think... but I have now 40/45 scopes and I am starting to change my mind.... lack of storage space mainly.

I want a few more scope models or brands I have not yet, sure but.... I have now decided that every new scope will  only be allowed if I get rid of an existing one, constant sum.
IOW I am getting more and more critical about my TE. I don't just buy the first vaguely interesting thing. I need to really want it.
I also try to diversify my TE to other types of TE than just scopes.. so for every new TE that comes in, a scope must go in the process.

I am trying to become half reasonable in my TE delirium...not saying it's easy, but I am trying....

I've had more than 45 scopes. But never at the same time. That's the trick 

Now now, bd... don't poke the frog with a stick. too hard.

Vince is coming around, I think... as he is exposed to better and better gear with a little help from his friends, it's pretty clear that his definition of what actually qualifies as an oscilloscope, etc is also being readjusted a wee bit, and he's realizing that a lot of those units he's been "gonna get round tuit" really aren't worth the "round tuits" they'll cost him.

Remember, I've also had to reevaluate similarly... it's a painful reckoning, to be sure. 

mnem
*tinker-tinker... putter-putter*

[Kosmic]

Yes you were right... but that Agilent still looks effing ugly to me, plus it was yellowed and had broken or missing CRT  bezel keys, no thanks.

Zero regret for not buying it, but very happy I bought that beautiful, lovely, Gorgeous proper original HP one instead.

A THOUSAND LASHES WITH A WET NOODLE! 

Haven't you learned where you are yet, Vince...? The only correct answer is "Of course, I want BOTH!"

mnem
There is no such thing as too many oscilloscopes.

That's what I USED to think... but I have now 40/45 scopes and I am starting to change my mind.... lack of storage space mainly.

I want a few more scope models or brands I have not yet, sure but.... I have now decided that every new scope will  only be allowed if I get rid of an existing one, constant sum.
IOW I am getting more and more critical about my TE. I don't just buy the first vaguely interesting thing. I need to really want it.
I also try to diversify my TE to other types of TE than just scopes.. so for every new TE that comes in, a scope must go in the process.

I am trying to become half reasonable in my TE delirium...not saying it's easy, but I am trying....

I've had more than 45 scopes. But never at the same time. That's the trick 

Now now, bd... don't poke the frog with a stick. too hard.

Video of Vince being poked:

https://youtu.be/HBxn56l9WcU?t=16

[mnementh]

ah yes, for those who are interested in the details ...      (you don't just screw stuff into the playfield ... fixing that kind of damage is an incredible amount of work.

I'll have to admit... I have been guilty of a similar "quick & dirty band-aid fix" on several occasions back when I did arcade repairs after school; the owner of course was not interested in paying to "do the job right".

In my defense, even then I did know enough to at least make sure the screws I used were small enough and too short to possibly in any way delaminate the upper layers of the plywood.

mnem
I have been a very bad tinkerdwagon... I must be pew-nished...

[Specmaster]

Well, that is a promising start, you can never be sure of what you are going to find when the seller does not show photos of them powered. So far you have an excellent score there, well worth the trip to collect them. Nixies are sought after in meters these days.

Probably a promising finish too. I can't even find the weston standard cell in the schematics!

I haven't found a manual for the True RMS AC Unit, and I'm not sure I can be bothered to randomly twiddle pots without knowing what they do.

I've already flipped one nixie DVM and I'll probably flip these, leaving me only a Fluke 8300A

Well, either way it should be a win as you should be well able to get back more than you paid for the lot 

[Specmaster]

Very loooooong (but also very rewarding) day today - one that had been in the making for at least three years now..  Several years ago I met a gentleman at a swap meet who, when he learned I collect old test gear and have a special affinity for nixie counters, told me he had a pair of old 524s in his basement that he wanted to give me.  I repeatedly offered to pay him something, anything for them, but he refused, just wanting them to go to a good home.  Between work travel and weather, the meetup never happened that first year, but we kept in touch.  Planned something after my early 2020 trip out west, but then of course the Coof hit and put the kibosh on everything for 2020 and 2021.  After things dried out this spring he was finally able to get them out of his basement and loaded into his car, so today I made a 330 mile (~530 km) round trip up to New Hampshire and retrieved them.

524B:      524C:      Model 64 DVM      -Pat

Awesome score, Pat. We look forwards to lots of tired iron pr0n pics, as we all know you do so very well! 

mnem
*raises a glass to fellow TEAs who are gone but not forgotten*

Thinking about Neo, has anyone heard of him lately?

[Specmaster]

<snip>
I've had more than 45 scopes. But never at the same time. That's the trick 

Using that system, I've had in the realm of 23, if I had them all at once, I would have had to build myself a shelter from them as I'd have been banished to sleeping in the garden sure by SWMBO 

[Robert763]

A small TEA
Bought this little digital thermometer kit on ebay for £19.95 including postage. I already have the similar looking MM2000 meter and some probes but no clamp probes. This MM2020 has two inputs so does differential and dual readings. It also has Kelvin indication.
I quite like the TME equipment. Not well known but british made and fully supported. Not cheap though. This is a current model. The meter is £140 and the complete kit is £330.
Happy at <£20.

[Vince]

Now now, bd... don't poke the frog with a stick. too hard.

Vince is coming around, I think... as he is exposed to better and better gear with a little help from his friends, it's pretty clear that his definition of what actually qualifies as an oscilloscope, etc is also being readjusted a wee bit, and he's realizing that a lot of those units he's been "gonna get round tuit" really aren't worth the "round tuits" they'll cost him.

Remember, I've also had to reevaluate similarly... it's a painful reckoning, to be sure. 

mnem
*tinker-tinker... putter-putter*

No not quite.... I didn't say I was seeking "better" and better gear, as in "moder modern and capable "...  though it's nice as well.

No I meant I was getting more critical in the sense that my "taste" for OLD stuff  is evolving, but it's still old "junk" in the grand scheme of things...

Out of my 40/45 scopes, the vast majority are scopes I REALLY like, and that I am extremely unlikely to ever part with.
Point is, these old scopes aren't plentiful nor cheap. Modern stuff is disposable :  want one ? Just spend the money and go on-line to get one, job done, a few clicks away.
Not so with older stuff. So every time I manage to lay my hands on some old piece gear that I like, it makes no sense to sell it later, because it's worth much more to me, as an emotional object, and the history behind it, and the fun I get out of playing with it, the joy of simply being able to look at it in the flesh up close... than the few bucks I could get, if at all, from selling it.

Half of my scopes are the glowing Tek scopes, they aren't going anywhere.  A third will be restored, the rest are invaluable as parts mules. Infinitely more useful to me for parts than the few bucks I would get from selling them.

There are only a very few scopes I would be OK to get rid of, and only a couple that I actually WANT to get rid of, because I don't like them and only bought them because they were cheap and I am hoping to make 50 Euros of profit once fixed. 

So the plan is to try to contain my scope "collection" / inventory to the current level, possibly lower it a bit by 3 or 4 maybe, but I don't see how it could ever get much lower than that.
All the parts mules are very valuable to me, bang for buck, so the plan I think, what makes most sense, is to keep them all for as long as technically / practically possible, and resort to selling as few as possible of them, only when I really, really need the space for something else. But for now I just keep gathering them.

[Vince]

Video of Vince being poked:

https://youtu.be/HBxn56l9WcU?t=16

I told you I agreed for an interview, fine, I enjoyed our conversation, but I never said I allowed you to upload it to freaking YT !!!   

[factory]

Well, that is a promising start, you can never be sure of what you are going to find when the seller does not show photos of them powered. So far you have an excellent score there, well worth the trip to collect them. N%*&s are sought after in meters these days.

Probably a promising finish too. I can't even find the weston standard cell in the schematics!

I haven't found a manual for the True RMS AC Unit, and I'm not sure I can be bothered to randomly twiddle pots without knowing what they do.

I've already flipped one n%*&e DVM and I'll probably flip these, leaving me only a Fluke 8300A

The Weston cell in the 1619 & 1620 is a tiny thing, in the 1619 it's hidden under a small cover behind the range switch, almost could be confused with a fuse, but it isn't one. And yes it's dead too. 











If you want to flip the 1420 DVM, then I would be very interested, I have to say they both look in much nicer condition then what I've found locally. 

Edit: Different version of Muirhead miniature standard cell used in some of these DVMs. Picture from here http://dexterslab2013.blogspot.com/2015/10/teardown-vintage-solartron-lm1619-volt.html


David

[factory]

OK thanks, will be looking at that.... can't buy anything right now but will see if I have some suitable cap in my stock...

I have new RIFAs, i.e. Kemet caps of same construction. Bought new, from Mouser, so OK now and well into my retirement. 100n, raster measurement ~15mm. 2 of those in an envelope is not a problem.

Wow, that's very kind of you, offer accepted, thank you very much !

I just zoomed on the picture I took of the PSU in my scope. Looks like the RIFA in it is marked 47nF, so replacing it with 100nF should be OK I guess...

See you in your PM ! 

Someone will correct me if I'm wrong, but I'm sure the RIFAmadness paper crap is in-between, the main DC filter cap and the switching transistor.  Not part of the mains input suppression, or filtering where they normally are fitted. The camera was on holiday when I pulled the board, to change the RIFA crap, so can't be certain of it's function.


Also be aware the power switch rod is quite fragile, mine broke despite following the manual.  Ended up with a zip tie bodge, round it to hold it in place.

David

[tggzzz]

Well, since we have reached page 2465, here's my "8 traces should be enough for anybody" picture.