Test Equipment Anonymous (TEA) group therapy thread

[BU508A]

Kind of a follow up to the last "Fun with TEA" topic:

Real (live 400V from the power outlet) 3 phase measurement using the WT1600:



Svp. appreciate schlepping that BFT (Big fucking transformer) from the basement to the lab to show off this picture

    

A small riddle (most probably suitable for the Europeans only): what is the error that I deliberately introduced here:

The order is looking a bit strange.
brown = L1
black = L2
grey = L3

[Neomys Sapiens]

Half cross-section on N?

[Vince]

The earth wire coming from the left, is not connected to anything... might as well not be there ?! 

[factory]

I've been working on the Tek 453 I got from PP auction earlier this year, as received it was very crusty & had the power cord cropped off an inch from the case. Opening the case I found the usual Sprague 109D wet tant cap in the PSU, which had sprayed it's acidic contents and eaten the track underneath.  There are quite a few axial wet tants in this scope, but thankfully only the one 109D.


First job was to replace the power cord, once I had separated the back cover, it was obvious why it was cut off, the rubber insulation had perished. It took me longer to find the lost roll of tin/lead/silver solder, than it did to fit a replacement power cord. 


Next job was to find something to replace the failed 3uF 150V tant with, nearest I had was a 4.7uF 250V alu electrolytic, it measured better on the Peak ESR, so in it went.
The open track was repaired with a link on the back.




It was powered up via the lamp limiter, no smoke signals with 40W or 100W bulbs, I had a crappy sine-wave trace with the 100W bulb (not pictured), this turned into a nice flat line once I bypassed the lamp limiter.  The front panel was then cleaned.
Here are both channels connected to the probe cal output & added together, channel 2 required a bit of gain adjustment prior to this.



Only things I still need to check are, the delayed timebase & PSU voltages, one of the graticule lamps is blown too.

David

[bd139]

Nice job as always. I think the 453 I had years ago had the same problem with the 109D that had exploded annoyingly.

Glad to see all the neons work on your front panel too 

[Vince]

VOLTAGE REGULATORS

Thanks people for your feedback. I have now enough information to confidently, expertly organize all my regulators : I will just shove them all into the same drawer and call it a day ! 

Well maybe not... I will just carefully ignore all prefixes and suffixes, and just sort them by voltage and polarity.

I don't have any low current ones, which I guess makes sense since I have only beefy TO220 and TO3 packages. Since these can put out 1 or 1.5Amp, why would any manufacturer artificially limit them to 500mA ?! So I guess the only 'L' 500mA ones are those supplied in small packages like TO92 or SOT23 surface mount something or other. I don't have these.

I do have a few LDO ones though, in the end :

- x3 of the SI-3000 series:  SI-3050, SI-3090 et SI-3120, respectively 5, 9 and 12V, as you would have guessed.
- L4805 , oh, that one breaks the rule already ! TO220 but limited to only 400mA !    Maybe it's inherent to LDO's ? Less current for a given package ?! 
- L4940V12  Ah, no, this one does give the full current... 1.5A, good boy 
- 278R05 oh boy this one puts out TWO amps !!! 


As for the CT/CV suffix thing, I downloaded a few datasheet and they all agree.. it's clear as water, it's indeed CV for TO220 package and CT for TO3, simple as that.
So how comes I have TO220 packages marked CT instead of CV ?! 
You don't believe me I am sure, so here is a picture.
At this point, I am inclined to decide that it was simply a mistake from the manufacturer and that's all ?! 
Look, all of them are brand new, all made by Motorola. Probably all from the same batch (same markings on all of them, look).  My dad ordered them for his work back in the day. So of course he ordered them all at once. So, I am inclined to say they are all from the same batch from some Motorola factory, and some guy operating the machine that marks the packages.. goofed it ?! 
Maybe the guy from the previous shift was making TO3 packages and when the next guy came for the afternoon shift, his manager asked him to make TO220 packages instead... and he forgot to reconfigure the machine... who the hell knows.... humans make errors after all...

Picture of my collection. I think they are all there.. I think. 69 of them no less. 11 TO3 and 58 TO220. So I have a bit of everything ! 
I don't have a negative 5.2V one for ECL logic chips though... but I can take a 7905 and put a Germanium diode in series with the feedback pin and problem solved ! 

Also have a weird one : 9.3 Volts ?!    Anyone knows what that's used for ?! Maybe a custom order for a big client...

Bonus pictures : today in the back yard, Coypus were back. A few weeks back I had 2 adults sharing the garden with 2 ducks, a male/female couple that comes to see me every year, like clock work, they seem married to each other...
So today no duck, two coypus but not two adults. Instead this time an adult and a baby coypu ! Look how cute he is ! 

And a bit later, this evening as I was watering my strawberries and tomatoes and raspberries.... oh, I saw a Hérisson !! Well that's what we call them here.... lemme google that.... click click click.... a " Hedgehog" it seems ??  A baby one too, isn't he cute ?! 

[Cerebus]

0.6̇66̇ - we have unicode. "combining dot above" does the trick.

How does that work then?

Just type the character you want to 'dot' (let's say "o"), and then follow it with "combining dot above" (U+0307) using whatever technique is appropriate to the operating system you're using and you get: ȯ. How clearly it comes out is very much a function of the font you're using.

Doesn't work for me.



EDIT: I use the standard forum font in 8pt bold, Verdana iirc.

Hacking your sentence:

I use the standard forum font in 8pt bold, Verdana iirc.

by inserting a bunch of U+0307 after every "o" yields:

I use the standard fȯrum fȯnt in 8pt bȯld, Verdana iirc.

i.e. it works. If you can't see it here (and I presume you could previously) you've likely got a problem with Unicode support in the font(s) you've got loaded. If you can see it but can't reproduce it then you've likely a problem with your Unicode input method.

[srb1954]

GENERALLY for IC's
Prefix is manufacturer specific (original one may be second sourced, bought out or cloned). e.g. LM National Semiconductor MC Motorolla
That is your first filter when looking for datasheets.
Suffixes are generally package type or other variations.
You find LM79xx because one datasheet covers all the voltages.

National had a numbering for a lot of linear devices where the first numeric character specified the temerature range. A LM117 was millitary range. LM217 was automotive/industrial and LM317 was commercial.

My understanding of the National Semiemployed prefixes was LM was Linear Monolithic, LH was Linear Hybrid, and DM was Digital Monolithic.  And the first number on the linear stuff was certainly a quick and easy way to differentiate the temp range.

-Pat

National also used:
   MM  MOS monolithic
   DS   Digital interface
   AH   Analog hybrid?
   LF    Linear FET?
   ADC Analog to digital
   DAC Digital to analog
and a whole host of other more specific prefixes.
   

[factory]

Nice job as always. I think the 453 I had years ago had the same problem with the 109D that had exploded annoyingly.

Glad to see all the neons work on your front panel too 

Only one that didn't light was the reset lamp, looking at the diagrams it can't light if the A sweep trig lamp in on, need to recheck tomorrow, note: the green lamps are all incandescent according to the book, the rest are neon.

David

[mnementh]

So what we established here is the standardization was a failure.

Failure is not an option; it comes baked in.

mnem

[mnementh]

Free entertainment!  https://www.eevblog.com/forum/dodgy-technology/the-non-linear-plasma-reactor/

 

I didn't even need to read it. The posting style says crazy. I am watching Simon avidly 

I left a constructive suggestion for improving his reactor.   

Can't go wrong with more Orgons! 

https://www.nonlinearplasma.com/s/Unified-Wave-Theory-Scott-Rennie-NLP.pdf

Do not waste more than 15 seconds in the above... just skim it.     This is disturbing at so many levels.       

Didn't I see that on a episode of The Flash...?

mnem
*SMH*

[Vince]

I've been working on the Tek 453 I got from PP auction earlier this year, as received it was very crusty & had the power cord cropped off an inch from the case. Opening the case I found the usual Sprague 109D wet tant cap in the PSU, which had sprayed it's acidic contents and eaten the track underneath.  There are quite a few axial wet tants in this scope, but thankfully only the one 109D.

Glad you managed to get it working... that now reminds me I have a 453 of my own taking up space under the bench.... bought 9 months ago... started work on it. Never saw a trace on the thing, no HV. As I was working on it I saw the magic smoke escape from the HV transformer.... which is not good a tall, me thought back then ! 
You all gave me good advice and info so maybe I will find the courage to unwind the transformer and see if I can fix the wire that blew. Hopefully I don't have to unwind the transformer 100% to find the scene of the accident... 

[bd139]

Nice job as always. I think the 453 I had years ago had the same problem with the 109D that had exploded annoyingly.

Glad to see all the neons work on your front panel too 

Only one that didn't light was the reset lamp, looking at the diagrams it can't light if the A sweep trig lamp in on, need to recheck tomorrow, note: the green lamps are all incandescent according to the book, the rest are neon.

David

Good luck. I thought the reset lamp on mine was blown as it didn't work either. It took me a while to work out that the wire was never actually soldered onto the lamp holder on the front panel. At least that one was easy to get to.

I have mentioned this before but this was the one in which the previous owner was a "repairer" and had established that the tunnel diodes were wonky and replaced them with 1n4148's  .

I realised about a month ago how dishonest he was because I reckon he actually pulled them and sold them then sold the scope as spares/repair.

[mnementh]

VOLTAGE REGULATORS

Thanks people for your feedback. I have now enough information to confidently, expertly organize all my regulators : I will just shove them all into the same drawer and call it a day ! 

I do the same. I have one whole plastic shoebox that is nothing but VR ICs sorted by form-factor into baggies and salvaged or cheap buck, boost, & buck-boost DC-DC converter modules. I treat them all as electronic Legos. 

mnem

[bd139]

I've been working on the Tek 453 I got from PP auction earlier this year, as received it was very crusty & had the power cord cropped off an inch from the case. Opening the case I found the usual Sprague 109D wet tant cap in the PSU, which had sprayed it's acidic contents and eaten the track underneath.  There are quite a few axial wet tants in this scope, but thankfully only the one 109D.

Glad you managed to get it working... that now reminds me I have a 453 of my own taking up space under the bench.... bought 9 months ago... started work on it. Never saw a trace on the thing, no HV. As I was working on it I saw the magic smoke escape from the HV transformer.... which is not good a tall, me thought back then ! 
You all gave me good advice and info so maybe I will find the courage to unwind the transformer and see if I can fix the wire that blew. Hopefully I don't have to unwind the transformer 100% to find the scene of the accident... 

Came across this the other day actually which might be helpful

[25 CPS]

He's mad.

Not at all.

If anything, I wouldn't have expected the kind of stereotyping and bashing I've seen here over the last day or two. That said, I have a real life and better use for my time and energy.

I'm not bashing Ham Radio. I'm simply reporting what I see and hear. The amateur community does the bashing all by themselves. All one has to do is tune the HF bands and a majority heard is plain jackassery and dumbasses.

That's the meat and potatoes of the issue right there, actual lived experience.  It is what it is unless you or I or anyone else are prepared to ignore it.

Mid-morning, one of my friends called from about halfway between his place and mine and it turned out we both had the day off so he drove out here and we jumped into my car since he hadn't been in my new car yet, had lunch at a restaurant nearby and took some pictures down by the lake.  One of the things were were talking about were cars and how even one sufficiently bad experience of the "I bought a Citation and I'll never buy GM again"-type to pick one example can be a lifelong deal breaker for things.  The same can easily be extended to anything, really, including hobbies.

Then again, we already have our share of frustrated old geezers around so we don't need any more on the air. Thanks for deciding to stay away.

I can't say that has changed my opinion for the better.

[tggzzz]

And a bit later, this evening as I was watering my strawberries and tomatoes and raspberries.... oh, I saw a Hérisson !! Well that's what we call them here.... lemme google that.... click click click.... a " Hedgehog" it seems ??  A baby one too, isn't he cute ?! 

They are cute but are effectively aircraft carriers for fleas! They are also good at eating garden pests like snails and slugs.

[Vince]

I've been working on the Tek 453 I got from PP auction earlier this year, as received it was very crusty & had the power cord cropped off an inch from the case. Opening the case I found the usual Sprague 109D wet tant cap in the PSU, which had sprayed it's acidic contents and eaten the track underneath.  There are quite a few axial wet tants in this scope, but thankfully only the one 109D.

Glad you managed to get it working... that now reminds me I have a 453 of my own taking up space under the bench.... bought 9 months ago... started work on it. Never saw a trace on the thing, no HV. As I was working on it I saw the magic smoke escape from the HV transformer.... which is not good a tall, me thought back then ! 
You all gave me good advice and info so maybe I will find the courage to unwind the transformer and see if I can fix the wire that blew. Hopefully I don't have to unwind the transformer 100% to find the scene of the accident... 

Came across this the other day actually which might be helpful

Thanks, will be watching that soon !

Can't justify the expense for a bespoke machine though... seeing as I paid 40 Euros for my broken 453 and a working one apparently costs not much more than that... there is one here right now for only 50 Euros... so overall not too hopeful for that scope 

[Vince]

VOLTAGE REGULATORS

OK, sorting these 69 regulators.. found only ONE +5V one... that's just not plausible at all !
So turns out I had already sorted the 7805 in a drawer of their own, a while back when I did a first pass at sorting all my junk months ago. I had forgotten about them....

So my collection is now 69 PLUS....  x23  +5V regulators ! x3 TO3 the rest TO220.


69 + 23 so I have 92 linear regulators. I guess that's not too bad, but it's frustrating to be so close to the 100 milestone ! 
... I guess I will fix that once I get to "processing" my 4 big boxes of scrap boards.... plenty of stuff to salvage 

[mnementh]

I think you missed my point... to completely repurpose said chill air delivery for keeping Butthead Bob frosty. That said... yes, I know it's silly. That was kinda the whole point.

That won't work, either. BTDTGTTS. (Yes, actually, I've worked in a morgue!)

So you're saying you've actually tried to refrigerate Butthead Bob's corpse (or someone like him ) under the raised floor, and you know it is a fail from personal experience...?

Do tell us more... 

mnem

[AVGresponding]

0.6̇66̇ - we have unicode. "combining dot above" does the trick.

How does that work then?

Just type the character you want to 'dot' (let's say "o"), and then follow it with "combining dot above" (U+0307) using whatever technique is appropriate to the operating system you're using and you get: ȯ. How clearly it comes out is very much a function of the font you're using.

Doesn't work for me.



EDIT: I use the standard forum font in 8pt bold, Verdana iirc.

Hacking your sentence:

I use the standard forum font in 8pt bold, Verdana iirc.

by inserting a bunch of U+0307 after every "o" yields:

I use the standard fȯrum fȯnt in 8pt bȯld, Verdana iirc.

i.e. it works. If you can't see it here (and I presume you could previously) you've likely got a problem with Unicode support in the font(s) you've got loaded. If you can see it but can't reproduce it then you've likely a problem with your Unicode input method.

I used the input methods as described in numerous places (like this); they all seem to be different, and I've tried every combination I can think of, but all I get from trying to add the dot for example, is a 3.

[Vince]

VOLTAGE REGULATORS

I don't have any low current ones, which I guess makes sense since I have only beefy TO220 and TO3 packages. Since these can put out 1 or 1.5Amp, why would any manufacturer artificially limit them to 500mA ?! So I guess the only 'L' 500mA ones are those supplied in small packages like TO92 or SOT23 surface mount something or other. I don't have these.

OK Murphy !

I have just finished sorting and organizing them all... just need to update my spreadsheet and print labels.... tomorrow. 2AM here I am going to bed.

So out of nearly 100 regulators.... guess what, yes I found ONE that proves me wrong... ONE TO220 package that's low current ! 

But it's not an 'L' , it's an 'M' !

A 78M12 ...so I pulled the datasheet and yeah, it's a 500mA version ! Why... why do these things even exist !   
Makes for a smaller pass transistor inside, makes the regulator half a cent cheaper maybe ? I guess for high volume commercial electronics it can count ?! 

So the 500mA version is an 'M'... so what is an 'L' ? I pulled the datasheet for that one as well. It's also a low current version indeed, but not 500mA, no.... the 'L' is only 100mA ! THESE are indeed the ones that come in the tiny packages, TO92 and surface mount.
Datasheet says these are intended mostly as an improved " Zener + resistor " replacement. I guess why not, makes sense...

Well thanks everyone for your participation, that was quite a refresher on these regulators. Think I now have my basics right...

 

[25 CPS]

I think I know why the seller on Facebook Marketplace hasn't bothered with the two messages I sent.  I re-checked the listing and it's been pulled, not marked as sold, just removed completely.  It was an Agilent U1253B that was put up for sale a week ago a short drive from home which would've integrated nicely with the other equipment in my portable toolkit, so that's unfortunate.

[AVGresponding]

VOLTAGE REGULATORS

I don't have any low current ones, which I guess makes sense since I have only beefy TO220 and TO3 packages. Since these can put out 1 or 1.5Amp, why would any manufacturer artificially limit them to 500mA ?! So I guess the only 'L' 500mA ones are those supplied in small packages like TO92 or SOT23 surface mount something or other. I don't have these.

OK Murphy !

I have just finished sorting and organizing them all... just need to update my spreadsheet and print labels.... tomorrow. 2AM here I am going to bed.

So out of nearly 100 regulators.... guess what, yes I found ONE that proves me wrong... ONE TO220 package that's low current ! 

But it's not an 'L' , it's an 'M' !

A 78M12 ...so I pulled the datasheet and yeah, it's a 500mA version ! Why... why do these things even exist !   
Makes for a smaller pass transistor inside, makes the regulator half a cent cheaper maybe ? I guess for high volume commercial electronics it can count ?! 

So the 500mA version is an 'M'... so what is an 'L' ? I pulled the datasheet for that one as well. It's also a low current version indeed, but not 500mA, no.... the 'L' is only 100mA ! THESE are indeed the ones that come in the tiny packages, TO92 and surface mount.
Datasheet says these are intended mostly as an improved " Zener + resistor " replacement. I guess why not, makes sense...

Well thanks everyone for your participation, that was quite a refresher on these regulators. Think I now have my basics right...

 

Didn't you find any TO-3 ones with a "K" suffix? The LM323K is 5V 3A, for instance. The LM7812K is rated for 1.5A.

[Zucca]

It was an Agilent U1253B

It reminds me this