Test Equipment Anonymous (TEA) group therapy thread

[AVGresponding]

      eBay auction: #115259069636

mnem
 

Hahah I have one of these, paid about a tenner shipped, useful for reminding apprentices to respect their elders amongst other things.

Paging Specmaster, Specmaster to the white courtesy phone, Discord is running

[mnementh]

Yeah, I thought it was a particularly promising looking example; should clean up very nicely. Will be interesting to see what it closes out at.

mnem
*tzzzzzzzzzzzzzt*

[AVGresponding]

Was it Cerebus who mentioned how to thin superglue down?

[nixiefreqq]

Only a box?
I have at least 5 Really Useful Box shallow tray type bins of just toroids. And a 19l one just for un-cased Variacs. I have 7 cased Variacs.  Found a 36.5V 25A C core transformer at the back of the garage too. 
On Vince's question my basis is

Don't keep ANY SMPS transformers (possible exception would be one made with a marked, known, core and has not been glued or potted.)
Don't keep any unmarked "consumer" grade transformers.
Keep any marked commercial / industrial transformers especially toroids and those from know manufacturers.
For CRT flyback I'd keep a couple if they have separate HV windings. An external rectifier is bonus too.

In all honesty, this was my reaction too.  But like I just said, I was trying to be good.

I'll take exception to your statement about "consumer" transformers... two consumer gadgets I love to rob transformers from are a) nukeboxen and 2) old stereos, even the bigger bookshelf "pregnant boombox" ones by AIWA, Panasonic and Sony, etc. Those always have a good 200-400VA continuous-duty transformer with two 25-60V secondaries. Perfect for making small homebrew linear power supplies, and if you like the result, you can turn it dual-output.

The nukeboxen transformers... ehhh... what can I say? Any way you power them, you can get into lots of interesting trouble. 

And then, let's not get started talking about my collections of wall-wart & power bricks (ranging up to 20V/12A) and my server PSU sickness, which I pared down to 2 102L storage tubs before the Great White North adventure... 

mnem
 

Ahh, one thing to remember is you are in 60 Hz land and we are in 50 Hz. Transformers that are OK at 60Hz can be marginal at 50Hz Most consumer tranasforers I've come across tend to desigined towards the 60 Hz end of the spectrum.

hmmmmmm.  strange that this has come up on the thread right now.

on thursday took a box of dry transformers (about 50 lbs) to the transfer station and tossed it into the metal recycling dumpster.

why?  had been lecturing swmbo that anything saved but not used in the last 5 years is not worth keeping.  she tossed a lot of her stuff (it surprised me how many half used rolls of xmas wrapping paper and lampshades we found).   then she pointed at my box of transformers and said "when have you ever dug thru that trip hazard and actually used one of them".  the honest answer......."never".   so it had to go.

do i risk being banned from the group for this confession?

stopped at the range on the way home and put lots of .357 inch holes in a target.  (was alone because of the sleet that was falling)  it made me feel better.

[Cerebus]

Was it Cerebus who mentioned how to thin superglue down?

Not me.

Edit: Although at a guess I'd say acetone ought to be compatible, or MEK, or methyl chloride, or anything else you might use to solvent weld PMMA (Perspex).

[AVGresponding]

Was it Cerebus who mentioned how to thin superglue down?

Not me.

Bugger...

Well, yer a hamateur chemist, wing it! Acetone? Can't get trichlorethane any more, hope it's not that.

[Robert763]

Another solution might be a nut splitter. It would definitely remove the nut although it may damage the threads in the process.

I'm sure I'll be able to loosen that nut as soon as I can get it properly clamped.

I know it probably goes without saying, and I wouldn't want to be accused of trying to teach you how to suck eggs, but I would mention that it would be best to use a 6-point socket rather than a 12-point, or indeed any other kind of spanner, excepting a 6-point box/ring.

Sometimes oxide "welding" can be broken with careful and judicious application of impact tools. A blunted automatic centre punch can be useful, also impact drivers though these are far more important to have a delicate touch with, on such small fasteners.

A "Flank-Drive" (Snap-on) or simlar ring spanner designed not to engage the points is even better than a 6 point. There are two problems:
The metal is so soft it distorts.
Even if you do break the weld, it will almost certainly re-weld as you turn it.

[Cerebus]

Was it Cerebus who mentioned how to thin superglue down?

Not me.

Bugger...

Well, yer a hamateur chemist, wing it! Acetone? Can't get trichlorethane any more, hope it's not that.

See edit above.

[Robert763]

All my old transformers, SLA bateries and even stripped chassis go to the metal re-cyclers. Last boot load raised £80 and I picked up a Time 1010 Voltage calibrator for £2 while I was there 

[AVGresponding]

Snap-On flank drive is widely copied; I've not seen a 6-point tool that doesn't have some version of it in years.

The softness of the metal is why you have to be very careful when using impact tools, though I have found they are superior.
It's a case of dynamic loading over static loading. I would also use the extended penetrating oil bath first.

[tautech]

Another solution might be a nut splitter. It would definitely remove the nut although it may damage the threads in the process.

I'm sure I'll be able to loosen that nut as soon as I can get it properly clamped.

I know it probably goes without saying, and I wouldn't want to be accused of trying to teach you how to suck eggs, but I would mention that it would be best to use a 6-point socket rather than a 12-point, or indeed any other kind of spanner, excepting a 6-point box/ring.

Sometimes oxide "welding" can be broken with careful and judicious application of impact tools. A blunted automatic centre punch can be useful, also impact drivers though these are far more important to have a delicate touch with, on such small fasteners.

A "Flank-Drive" (Snap-on) or simlar ring spanner designed not to engage the points is even better than a 6 point. There are two problems:
The metal is so soft it distorts.
Even if you do break the weld, it will almost certainly re-weld as you turn it.

Often yes, but you don't, instead you gently work it back and forth getting it a little more and more. Gently gently is the secret and when it looks like the threads might bind some lubricating penetrant can save the day.

[Vince]

Sorting stuff is going not too bad, lab should be operationnal in a couple weeks maybe... managed to clear a bit of space on the bench, so I thought hey, let's treat myself with a bit of early lab fun, to keep me motivated...

While sorting through lots of really ancient stuff my old friend gave me... I excavated this thing. A 1MHz crystal oscillator... a chunky one as you can see. Including its mounting base, it's 15cm high. Base is 65x65mm.  Oscillator "can" itself is 10cm high, 50x50mm cross section.

No date on it, but looking really old eh... not sure it would fit in these modern smartphone gizmos...
Has a vacuum tube-like 8 pin connector, and inside the base, an old Allen-Bradley carbon composition resistor.
There is a nice multi-turn Bourns trimmer in the base, to let you finely adjust the frequency.

The plaque on it gives no date. Says it's made by " Vectron Laboratories, Inc, Norwalk, Connecticut ".  Sounds serious ! 

Model : 204-1526

Serial Number : 41764  so quite a popular unit I guess...

Google is not very talkative on that one... needless to say it didn't find me a datasheet, spec, or wiring for it...
It barely managed to show me a few pics of more modern Vectron oscillators, and that Microchip apparently acquired Vectron at some point.
So I guess it must have been a well known  / valuable brand back in the day.

Couldn't resist the temptation of playing with it... would it still work after 50+ years ??

There are only 3 wires coming out of it... black red and a coax cable... sounds simple enough.

So I scoped the signal from the coax cable while ramping up the supply voltage slowly... 1 Volt.... 2volts.... 3 volts... 4 volts....5 Volts.... still no output whatsoever at 5V meh.... maybe it's broken 

But it's old so maybe it needs more than 5V... but how much ?! Well seeing that I had nothing to lose really, I just kept increasing the voltage slowly hoping at some point it would come to life...

At about 8.5V all a of sudden I get a signal !!!     A nice clean stable sine wave, bang on 1MHz according to the scope cursors, looking good !!
This bastard is still alive !!     At this voltage, it draws 70mA and the sine wave measures about 1 Vpp.

Then I noticed that if I kept increasing the supply voltage... amplitude of the signal would increase as well ! Eh ?!
So how do I know where to stop not to fry it ?! 

I slowly kept increasing the voltage.... until I got to about 23Volts, because I noticed that at this point, suddenly the amplitude of the sine wave stabilizes. No clipping or any bad effect that I can see on the scope... no it's just that the amplitude found its plateau. So I stopped there.  At that point, device draws 210mA and the amplitude of the sine wave is nearly 5Vpp.

That's close to 5 Watts, quite a lot, so assume there must be some heating going on, maybe some temperature regulation as well, I don't know.

Since it looked bang on 1.00MHz on the scope, and stable, I went further and measured it more accurately on my old Metrix Nixie counter. Obviously it was cold, the Vectron was barely warm, and it's just a not so accurate counter trying to measure an oscillator of completely unknown specs.... so it's fair to say it was not exactly 5 star science ! But I don't care, it's for fun eh, gimme a break, wanted to see what the counter would say anyway, and how the measurements would evolve over the course of a few minutes.

Just after power up, dead cold, the counter measured 1,000,016 Hz , going down slowly and at a constant rate. After a few minutes it reached spot on 1,000,000 Hz so obviously I had to take a picture ! 
Then a few seconds later it got to 999,999 Hz at which point I totally lost interest ! 

Now that I know it works, I just can't get myself to throw it away.. so I will keep it.
Plus hey, if the temperature is regulated, who knows, given its large size maybe it's super stable and accurate and it might well be my best time base in the lab ! 
So one more reason for keeping it...


This video was brought to you by Electro-Frog  Comment down below if you have the datasheet for this thing. Please like subscribe and don't forget to click that Bell.  You can support me on Patreon and donate via Paypal. Oh and don't forget my cool Electro-Frog merch , look at all the cool stuff available in my store ! 

OK done for the fun... now back to sorting stuff.... 

[Robert763]

Another solution might be a nut splitter. It would definitely remove the nut although it may damage the threads in the process.

I'm sure I'll be able to loosen that nut as soon as I can get it properly clamped.

I know it probably goes without saying, and I wouldn't want to be accused of trying to teach you how to suck eggs, but I would mention that it would be best to use a 6-point socket rather than a 12-point, or indeed any other kind of spanner, excepting a 6-point box/ring.

Sometimes oxide "welding" can be broken with careful and judicious application of impact tools. A blunted automatic centre punch can be useful, also impact drivers though these are far more important to have a delicate touch with, on such small fasteners.

A "Flank-Drive" (Snap-on) or simlar ring spanner designed not to engage the points is even better than a 6 point. There are two problems:
The metal is so soft it distorts.
Even if you do break the weld, it will almost certainly re-weld as you turn it.

Often yes, but you don't, instead you gently work it back and forth getting it a little more and more. Gently gently is the secret and when it looks like the threads might bind some lubricating penetrant can save the day.

That is true for corrosion or sealant but not galling. Back and forth movment allows release of corrosion products but just promotes galling. It's actually the aluminium oxide layer that stops galling, working back and forth breaks that layer down and allows galling. Normal lubricants don't help much unfortunatly.

[Robert763]

Sorting stuff is going not too bad, lab should be operationnal in a couple weeks maybe... managed to clear a bit of space on the bench, so I thought hey, let's treat myself with a bit of early lab fun, to keep me motivated...

While sorting through lots of really ancient stuff my old friend gave me... I excavated this thing. A 1MHz crystal oscillator... a chunky one as you can see. Including its mounting base, it's 15cm high. Base is 65x65mm.  Oscillator "can" itself is 10cm high, 50x50mm cross section.

No date on it, but looking really old eh... not sure it would fit in these modern smartphone gizmos...
Has a vacuum tube-like 8 pin connector, and inside the base, an old Allen-Bradley carbon composition resistor.
There is a nice multi-turn Bourns trimmer in the base, to let you finely adjust the frequency.

The plaque on it gives no date. Says it's made by " Vectron Laboratories, Inc, Norwalk, Connecticut ".  Sounds serious ! 

Model : 204-1526

Serial Number : 41764  so quite a popular unit I guess...

Google is not very talkative on that one... needless to say it didn't find me a datasheet, spec, or wiring for it...
It barely managed to show me a few pics of more modern Vectron oscillators, and that Microchip apparently acquired Vectron at some point.
So I guess it must have been a well known  / valuable brand back in the day.

Couldn't resist the temptation of playing with it... would it still work after 50+ years ??

There are only 3 wires coming out of it... black red and a coax cable... sounds simple enough.

So I scoped the signal from the coax cable while ramping up the supply voltage slowly... 1 Volt.... 2volts.... 3 volts... 4 volts....5 Volts.... still no output whatsoever at 5V meh.... maybe it's broken 

But it's old so maybe it needs more than 5V... but how much ?! Well seeing that I had nothing to lose really, I just kept increasing the voltage slowly hoping at some point it would come to life...

At about 8.5V all a of sudden I get a signal !!!     A nice clean stable sine wave, bang on 1MHz according to the scope cursors, looking good !!
This bastard is still alive !!     At this voltage, it draws 70mA and the sine wave measures about 1 Vpp.

Then I noticed that if I kept increasing the supply voltage... amplitude of the signal would increase as well ! Eh ?!
So how do I know where to stop not to fry it ?! 

I slowly kept increasing the voltage.... until I got to about 23Volts, because I noticed that at this point, suddenly the amplitude of the sine wave stabilizes. No clipping or any bad effect that I can see on the scope... no it's just that the amplitude found its plateau. So I stopped there.  At that point, device draws 210mA and the amplitude of the sine wave is nearly 5Vpp.

That's close to 5 Watts, quite a lot, so assume there must be some heating going on, maybe some temperature regulation as well, I don't know.

Since it looked bang on 1.00MHz on the scope, and stable, I went further and measured it more accurately on my old Metrix Nixie counter. Obviously it was cold, the Vectron was barely warm, and it's just a not so accurate counter trying to measure an oscillator of completely unknown specs.... so it's fair to say it was not exactly 5 star science ! But I don't care, it's for fun eh, gimme a break, wanted to see what the counter would say anyway, and how the measurements would evolve over the course of a few minutes.

Just after power up, dead cold, the counter measured 1,000,016 Hz , going down slowly and at a constant rate. After a few minutes it reached spot on 1,000,000 Hz so obviously I had to take a picture ! 
Then a few seconds later it got to 999,999 Hz at which point I totally lost interest ! 

Now that I know it works, I just can't get myself to throw it away.. so I will keep it.
Plus hey, if the temperature is regulated, who knows, given its large size maybe it's super stable and accurate and it might well be my best time base in the lab ! 
So one more reason for keeping it...


This video was brought to you by Electro-Frog  Comment down below if you have the datasheet for this thing. Please like subscribe and don't forget to click that Bell.  You can support me on Patreon and donate via Paypal. Oh and don't forget my cool Electro-Frog merch , look at all the cool stuff available in my store ! 

OK done for the fun... now back to sorting stuff.... 

That is a very nice oscilator, Oven controlled. Almost certainly designed to run of 24V so you can ramp it up a little. Let it warm up and watch the frequency when you gently set it on its side. One side should make the frequency go up, tilting over onto  the opposite side make it down.
This is the effect of a +_ 1G force of gravity change on the crystal.
If throwing it out thro it my way 

[srb1954]

More TEA.
A small package arrived today. A Palladin tools "Cable Check PC". Been lookin for one of these at a reasonable price for awhile. They seem to go for £50-60. I picked this one up for £30 shipped. It is in as new condition complete with original box and sleeve, albeit a bit tatty.

I got this same model of tester many years ago but hardly ever use it these days. Really the only test socket combination that is still useful with modern computer cabling is the RJ-45 socket on the top edge.

It would probably be much more useful device for the typical forum member if it had a 24 pin Amphenol connector for testing GPIB cables!

[tautech]

Another solution might be a nut splitter. It would definitely remove the nut although it may damage the threads in the process.

I'm sure I'll be able to loosen that nut as soon as I can get it properly clamped.

I know it probably goes without saying, and I wouldn't want to be accused of trying to teach you how to suck eggs, but I would mention that it would be best to use a 6-point socket rather than a 12-point, or indeed any other kind of spanner, excepting a 6-point box/ring.

Sometimes oxide "welding" can be broken with careful and judicious application of impact tools. A blunted automatic centre punch can be useful, also impact drivers though these are far more important to have a delicate touch with, on such small fasteners.

A "Flank-Drive" (Snap-on) or simlar ring spanner designed not to engage the points is even better than a 6 point. There are two problems:
The metal is so soft it distorts.
Even if you do break the weld, it will almost certainly re-weld as you turn it.

Often yes, but you don't, instead you gently work it back and forth getting it a little more and more. Gently gently is the secret and when it looks like the threads might bind some lubricating penetrant can save the day.

That is true for corrosion or sealant but not galling. Back and forth movment allows release of corrosion products but just promotes galling. It's actually the aluminium oxide layer that stops galling, working back and forth breaks that layer down and allows galling. Normal lubricants don't help much unfortunatly.

All true however every case is different. Tiny to and fro movements are what's required to help powder the corrosion products and create small clearances for lubricating penetrants to penetrate and help prevent further galling.

Most times I win but still get caught occasionally however the more tricks you have in the arsenal the more lucky you'll be.
Often stuck shafts like Med has are due to too finer manufacturing clearances and engineers don't do that on purpose, they do it in error as they never get to see their work decades later so to understand 'weathering/ageing' processes.
It's an art in itself freeing up frozen fasteners. 

[AVGresponding]

Off to bed after an entertaining evening on Discord.

Checking back here however has given me a new phrase of the day, I hope to use it later on: "Electro-Frog".   

[vk6zgo]

Don't hurry this Mike, remember you're retired and don't need to panic. Let it stand in a low viscosity penetrant for a bit.

Agreed. Especially since chances of finding a replacement shaft of that length and 9 positions will be slim to none.

Forget Water Displacement formula 40, instead if you have some 2 stroke fuel try that but in the garage of course unless you have a furnace working there.

RP7 used to be useful, but seems to have gone off the market.

I have found  either diesel fuel or "Mineral turps" to do a good job, in fact, the latter is my "go to" for various problems, not limited to "de-sticking" shafts.
I've also used it to remove carpet glue/underlay crap from a wooden floor & remove "gunked in" batteries in a Yaesu Hand held radio battery pack.

Yes, it stinks & is a pain to clean up after, but it works.

[mansaxel]

anything else you might use to solvent weld PMMA (Perspex).

What would one use to solvent weld Perspex? I realise there are suggestions in the text I cut, but I'd like to read your thoughts on that. I've tried CA for glueing it and been less happy. (It probably was application error; when I tried to glue two flat sheets together I got good results. When I tried to glue at an angle, it broke too easily; I'm assuming from less contact area, not straight pieces et c.)

[Cerebus]

anything else you might use to solvent weld PMMA (Perspex).

What would one use to solvent weld Perspex? I realise there are suggestions in the text I cut, but I'd like to read your thoughts on that. I've tried CA for glueing it and been less happy. (It probably was application error; when I tried to glue two flat sheets together I got good results. When I tried to glue at an angle, it broke too easily; I'm assuming from less contact area, not straight pieces et c.)

You'd think that gluing Poly Methyl Methacrylate with methyl cyanoacrylate glue would be close to the perfect combination wouldn't you? PMMA and cured cyanoacrylate are almost the same plastic, and certainly have very similar physical properties. My experience has been the same as yours, total pants. I'm guessing it's a surface energy thing, like trying to join cold, set paraffin wax with hot liquid paraffin wax, they never truly fuse. Perhaps there's a primer that would make it work well, but those primers tend to be (a) very material/glue combination specific, (b) bloody expensive, and (c) difficult to find.

I've got some generic primer for low surface energy plastics for cyanoacrylate that's pretty good. It managed to stick PTFE to hard TPE rubber with CA glue - which is pretty impressive. Not a perfect, highly strong bond, but good enough to keep some 'skids' I'd cut out of PTFE sheet stuck to the bottom of the rubber feet of a steel framed chair that gets used every day for a year or two at a time. I have to re-stick them from time to time. I might give it an experimental try if I can find where my PMMA scraps have got to.

Methylene chloride used to be the standard for solvent welding PMMA, but chlorinated solvents have fallen out of favour (REACH and friends, much lower occupational safety limits, higher PPE requirements, and so on). It worked well, and with a bit of practice it was possible to produce invisible, optically clear joins that were as strong as the native material. Acetone will work, but is too fast evaporating to be really satisfactory; also there's more risk of solvent crazing.

Nowadays it is much easier to get proprietary solvent welding mixtures and I have to say that my experiences with them have been disappointing. Some of them must work well because people are still producing new display cases, aquaria and the like that look as good as ever, but the ones that I've tried haven't been up to snuff. Slower to gel the plastic, slower to dry, and don't seem to produce joints as strong, or as reliably. I've had to have a second try on failed joints on more than one occasion.

I've even had one mixture specifically sold for solvent welding PMMA that just didn't seem to work at all, and that was on a joint properly prepared for capillary solvent welding. I even tried joining two flat sheets with a lap joint (an essentially perfect surface for capillary solvent welding) just to see if it would work then, and all I got was a cloudy area on both pieces and a join with so little mechanical strength that it failed just from me picking it up from just one side of the joint. WTF?

Perspex^TM themselves recommend a range of acrylic adhesives and cements from Bostik sold under the Tensol® name for PMMA to PMMA bonding. For bonding PMMA to other substates they recommend a CA adhesive, specifically Bostik 7452 - go figure.

[Brumby]

RP7 used to be useful, but seems to have gone off the market.

Selleys RP7 is still around.  You don't see it as prominently as WD-40 has taken the front position in the market, but I've seen it in hardware and auto stores.

[cdev]

Vectron used to make boat anchor sized but nice rack mountable frequency measurement apparatus. You should poke around for a manual for your (ovened? 1 MHz frequency standard?) Or maybe ask on time-nuts@lists.febo.com if anybody there knows anything about it.

Vectron was a quality maker of test equipment in the 1950s and 1960s.

The pre-HP days.

[Brumby]

Only a box?

If that was a reference to my post, then I feel I should qualify my statement....

I don't exactly have a single, dedicated box for my transformers.  Some are still inside the equipment they came in since there is other stuff in those units that are potentially useful and keeping things intact means things are protected and their prior use topology is preserved.  There is a bit of a space penalty, but they tend to stack better.  I do have a box with smaller (<=60VA) transformers I have pulled together, but I know there are others floating around in some odd spots that I have yet to curate.

The one location I do know about is what I call "the DVD".  It's a full size DVD player case that has been gutted and several transformers have been mounted inside.  Originally it was used as a DIY stepdown from 240V to 115V (or thereabouts).  I put this together for testing an imported guitar amp (for a friend), so I could measure the voltage rails.  This was so I could look for a suitable 240V transformer to swap in.  I had to do my own investigation as, when I approached the manufacturer about getting a schematic or at least the specs for the transformer, they simply replied that it was "impossible" and told me nothing.  (spolier - it now works fine on 240V) I found a suitable toroidal with a 20% greater VA rating than needed, but slightly lower secondary voltage for the power amp (the 15V secondary was spot on)  I felt comfortable that the voltage sag of the original transformer while under load would bring it much closer to the transformer I found.  I also replace the mains caps and fuse to suit 240V operation.

This "DVD" was repurposed last year when the refrigerator started tripping the safety switch ... again.  The last time this happened, it was a defrosting element gone leaky - which cost half an arm to fix.  Not going there again, so time to replace it - but I needed to keep the thing running while that was organised.  The simple thing would be to run a lead with no Earth connection, knowing what the problem was.  That didn't sit comfortably, so I looked at an isolation transformer option.  I upgraded the "DVD" with a mix of (appropriately grouped) transformers to get 240V, but the compressor wouldn't start, so I paralleled a couple more to increase the VA.  That worked.

The two toroids were salvaged from some gear I scored from Doug Ford when he was moving some years ago.

This little exercise also won big points with SWMBO when it came to "all that stuff" I keep hanging on to.

[Saskia]

just got back from a trip to pick up my stuff ...
managed to load about half of it.
among my preeecioussss:
Outrun Arcade
Twilight Zone pinball
Fish Tales
Judge Dredd pinball
High Speed pinball cabinet
Spares ...

[Robert763]

More TEA.
A small package arrived today. A Palladin tools "Cable Check PC". Been lookin for one of these at a reasonable price for awhile. They seem to go for £50-60. I picked this one up for £30 shipped. It is in as new condition complete with original box and sleeve, albeit a bit tatty.

I got this same model of tester many years ago but hardly ever use it these days. Really the only test socket combination that is still useful with modern computer cabling is the RJ-45 socket on the top edge.

It would probably be much more useful device for the typical forum member if it had a 24 pin Amphenol connector for testing GPIB cables!

Just make up a 25 D to GPIB adapror cables. Or use the ready made IEC 625  (60625) adaptors.