Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

   

Oh.... this is promising. Looks like the calibration seal I noted in the original listing is still intact. It may very well be un-messed-around-with. 

What's this? Is this an HP Asset Tag?!? Could I have an HP that was actually USED AT HP? Or is it just a Factory Calibration ID?

mnem

[Cerebus]

I buy my isopropanol in the UK in 5L containers from the usual suspects on ebay. Last one came from lincs-products and they are currently selling 5L 99.9% at £17.99 delivered. I get through buckets of the stuff.

[bd139]

   

Oh.... this is promising. Looks like the calibration seal I noted in the original listing is still intact. It may very well be un-messed-around-with. 

What's this? Is this an HP Asset Tag?!? Could I have an HP that was actually USED AT HP? Or is it just a Factory Calibration ID?

mnem

Looking good.

I buy my isopropanol in the UK in 5L containers from the usual suspects on ebay. Last one came from lincs-products and they are currently selling 5L 99.9% at £17.99 delivered. I get through buckets of the stuff.

I stopped buying it on ebay when someone sent me a bottle of hydrogen peroxide instead.

Mainly because SWMBO was worried when I started suggesting I have a bash at synthesizing TATP  (no I didn't do it - that stuff is too deadly even for me - Look ma no hands!)

Edit: just ordered a metric shit ton of SMA parts on Aliexpress for less than ONE of the parts on RS. Let's see how bad cheap SMA stuff is. Worth a go.

[Specmaster]

   

Oh.... this is promising. Looks like the calibration seal I noted in the original listing is still intact. It may very well be un-messed-around-with. 

What's this? Is this an HP Asset Tag?!? Could I have an HP that was actually USED AT HP? Or is it just a Factory Calibration ID?

mnem

Looking good.

I buy my isopropanol in the UK in 5L containers from the usual suspects on ebay. Last one came from lincs-products and they are currently selling 5L 99.9% at £17.99 delivered. I get through buckets of the stuff.

I stopped buying it on ebay when someone sent me a bottle of hydrogen peroxide instead.

Mainly because SWMBO was worried when I started suggesting I have a bash at synthesizing TATP  (no I didn't do it - that stuff is too deadly even for me - Look ma no hands!)

Edit: just ordered a metric shit ton of SMA parts on Aliexpress for less than ONE of the parts on RS. Let's see how bad cheap SMA stuff is. Worth a go.

Well now, that sure looks good because unless someone has perfected the art of removing seals and then reapplying them again and making it appear that the have not been touched, I'd plug it in and fire it up, I reckon its going to be a winner just like my Fluke 8840A and HP 3468A was.

[bd139]

As a glass half full sort of person, the battery might be flat yet 

Self cal on those isn't that terrible though and even without a 6.5 digit or better calibrator as long as the scale is correct then relative measurements are good enough.

[mnementh]

Well now, that sure looks good because unless someone has perfected the art of removing seals and then reapplying them again and making it appear that the have not been touched, I'd plug it in and fire it up, I reckon its going to be a winner just like my Fluke 8840A and HP 3468A was.

Fuse tests good; Infinity across the mains open circuit, and and 94 Ohms with it turned on. Think I may give it a go without opening it up, since I just unearthed my old dim bulb tester from the Projection TV daze... Hopefully won't make the RIFAs barf their guts out if there are any...

mnem
*wibble*

[bd139]

I'd crack it open and inspect first:

1. Cracked RIFAs.
2. Battery spillage.
3. Leaking caps.

A lot of the time the RIFAs don't go off until about an hour after you power it up.

[mnementh]

   
Welp... definitely not DOA, but does have issues. POST is successful, but when it defaults to DCV AUTO it starts with 200-300mV reading, and then starts creeping upwards. After a minute or so it's ~2.5V. Also, 2-Wire Ohms reads OVLD M no matter what I do with the test leads; open or short. 4-wire mode and AC seem to default to typical idle readings.

Def need to tear it apart; but nice that it's not already smoked, and not tampered with after the auction. Need to read the destructions from cover to cover too... and need the service manual. But not until after my taxes are done. 

mnem
moo.

[bd139]

Exercise the F/R switch a few times. May be that simple. DCV will drift unless shorted as on low range it’s 100M Zin.

[mnementh]

OH POOP.

Even after double and triple-checking the legend, and exercising the F/R button, I STILL set it bass-ackwards for the front jacks.   

Popped it to what I was SURE was the back jacks, and now it seems to respond normally to shorting in both DCV and 2-WIRE OHMS modes. 

I'll read the manual again when I get to a stopping point in my paper sorting; probably lots of other user error just waiting for a chance to get all over me.

mnem
*p00t!*

[xrunner]

OH POOP.

Even after double and triple-checking the legend, and exercising the F/R button, I STILL set it bass-ackwards for the front jacks.   

Popped it to what I was SURE was the back jacks, and now it seems to respond normally to shorting in both DCV and 2-WIRE OHMS modes. 

I'll read the manual again when I get to a stopping point in my paper sorting; probably lots of other user error just waiting for a chance to get all over me.

3478A & 3468B after ~5 minutes.

[Specmaster]

Great news, have you checked the readings against a standard yet? The HP meters do creep upwards on the DC volts range if left open circuited, as bd139 said, its due to the very high input impedance on the low V setting. I also find that Fluke 8840A will do likewise but to a much less extent, their input impedance is 10,000M on the first 3 DC V ranges 200mV, 2V and 20V and then 10M on the rest.

[Specmaster]

OH POOP.

Even after double and triple-checking the legend, and exercising the F/R button, I STILL set it bass-ackwards for the front jacks.   

Popped it to what I was SURE was the back jacks, and now it seems to respond normally to shorting in both DCV and 2-WIRE OHMS modes. 

I'll read the manual again when I get to a stopping point in my paper sorting; probably lots of other user error just waiting for a chance to get all over me.

mnem
*p00t!*

If the button is depressed then the back terminals are in play and with button showing the most, then the front terminals are the ones, its easy once you get used to it.

[mnementh]

Great news, have you checked the readings against a standard yet? The HP meters do creep upwards on the DC volts range if left open circuited, as bd139 said, its due to the very high input impedance on the low V setting. I also find that Fluke 8840A will do likewise but to a much less extent, their input impedance is 10,000M on the first 3 DC V ranges 200mV, 2V and 20V and then 10M on the rest.

Yeah, I've had 10Gohm meters before; but I don't recall ever seeing more than 1.2V, usually no more than 0.5-0.8V unless there was a strong source of static charge or pulsed DC (like a large CRT) nearby. May be related to the much greater everyday saturation of EMI now vs then as well.

mnem
*Father-offspring couch-potato time*

[Specmaster]

If anyone is looking at buying a ultrasonic cleaner in the future and don't need anything too expensive or large but capable of of accepting a PCB of upto 11cm by 10cm or 80cm by 13cm then you might like to keep your eyes open for one appearing in Lidl anytime soon as they usually have their special offers / buys repeated at least once a year and so it must be about to due to be on sale again soon.

I attach photos of mine that I purchased last year and then I forgot I even had it  I think I paid something like £20 for it and I had occasion to use it today and it made a very good of clearing out rusty sludge residue that was in my DAB module on a stereo I purchased on Ebay recently which is now installed and working perfectly.
 

[tautech]

Great news, have you checked the readings against a standard yet? The HP meters do creep upwards on the DC volts range if left open circuited, as bd139 said, its due to the very high input impedance on the low V setting. I also find that Fluke 8840A will do likewise but to a much less extent, their input impedance is 10,000M on the first 3 DC V ranges 200mV, 2V and 20V and then 10M on the rest.

Yeah, I've had 10Gohm meters before; but I don't recall ever seeing more than 1.2V, usually no more than 0.5-0.8V unless there was a strong source of static charge or pulsed DC (like a large CRT) nearby. May be related to the much greater everyday saturation of EMI now vs then as well.

mnem
*Father-offspring couch-potato time*

Not in a Peak Hold mode is it ?

[Specmaster]

No, 3478A's don't have a peak hold function. It's normal for a 100Mohm impedance meter to do this if the input is open circuited.

[tautech]

No, 3478A's don't have a peak hold function. It's normal for a 100Mohm impedance meter to do this if the input is open circuited.

Hmmm, The 10G inputs in SDM3kX models don't. 

[med6753]

Wow, I'm off line for 2 days and it's taken me over an hour to catch up. Can't possibly respond to everything other than to say that my Fluke 8800A has very high input impedance and it reads wacky too with nothing connected. It's normal.

The reason for my absence? Was with the lady from yesterday afternoon until I got home a while ago. For the past few months she's had some chronic pain in the right side of her chest. She had colon cancer about 10 years ago but tests conducted just last year revealed that she was clear. Obviously we were afraid that the cancer had returned.  Some tests including a CAT scan revealed nothing. Today I had to take her for an endoscopy in NYC. The result? An inflamed esophagus treatable with medication. It was a great relief for both us. 

Came home tonight fighting NYC rush hour traffic. Normal 2 hour drive took over 3 hours.   

   

[Carl_Smith]

So I have some actual content for the TEA thread, rather than just lurking and making comments on other people's posts. 

Excellent.

...four HP 3465A bench multimeters.

3465A or 3456A?

They are 3465A.

But recently the one working 3465A developed a strange fault.  Instead of giving a proper reading, it would count up for a fraction of a second, and then freeze that count for a fraction of a second, then count up again.  When the reading was frozen it was not correct.  It just seemed random.  Now this meter is the piece of equiment in question from a while back when I told the story of going to the trouble of searching the net to find an owners manual and later discovering that I had a real paper manual sitting a few feet from me the whole time.

Ah, yes, I remember that manual.

I found one really nasty solder joint on a pin of an IC, on the solder side of the board.  It wasn't just a cold joint or a cracked joint.  It has some black crud on it, and what looks like tiny crystals of something around the component lead.  And some stray fuzz.  Looked pretty nasty under the microscope.

Yep, sure does look like an electrolyte spill.

But I cleaned it up and resoldered it and now it works again. 

 

That inspired me to get out the next closest to working of the remaining three meters and have a crack at fixing it.  Its problem was that it worked fine but the display had no decimal point and sometimes the digits didn't light evenly.   Turns out these meters have wide ribbon cable going to the display that looks like it was made by laminating metal strips between plastic, not like modern flex circuits are made.  And the metal strips had come loose from the backer plastic at the ends.  I tried to glue some of them down but in the end gave up and just cleaned them and the connectors and carefully put it back together making sure the metal strips didn't fold back when inserting the cable into the connectors and now it works as well.

That sounds like a pretty delicate operation. What kind of glue did you try? Cyanoacrylate? Epoxy?

I tried cyanoacrylate but it wouldn't even stick to the "plastic" layer (maybe it's something more "interesting" like teflon?).  And I even used the good old liquid type.  I've recently discovered that the "super glue gel" that is hyped up as easier to use doesn't actually work as well.  I've found things that it won't glue well that the liquid type actually glues well.  I feel like I've been lied to by the super glue marketing people, but now I know better. 

Not that I needed two more working bench multimeters...

It's better than two more non-working ones.

Yeah, but I keep telling myself that I need to spend my free time on things more productive than fixing old meters that I don't need anyway, or trying to sell my old junk items on eBay that only go for $5 profit but it take me an hour to package up and ship.  I've got plans for projects and stuff that I never get around to.

I do have two more of these meters.  One of them probably isn't worth any effort to fix as it's missing half the buttons and the back corner of the case is busted out.  But the other one might still be repairable.   I checked eBay and there are several listed for around $50 and several that sold from $25 to $100 each.  Maybe I should sell them.   And then there's those two Heathkit scopes I got at the same time.  Last I remember when I powered them up maybe 10 years ago one worked and the other showed no signs of life.  I didn't investigate further...

[mnementh]

         

So after reading the manual again quickly to see how it runs in defaults... I tried again after letting it idle 30 minutes to warm up with leads shorted so auto-zero could do its thing. Shorted seems pretty good... so tried against the AD584LH reference. 10V reference here is bouncing between 10.004-005 on the Fluke, and 2.5V reference stable at 2.5020 on the Fluke.

When I first shorted out the leads in OHMS, it read ~6ohms; after I finished with REFERENCE DCV, I tried again in OHMS and it read 0.0967something, which is not far off the ~0.10 ohms shown for those leads shorted and plugged into the Fluke and the DE-5000. Curious, I tried a little percussive diagnostics; and bam, resistance jumped up around 11 ohms. Looks like I have an intermittent in the resistance section, or a cruddy F/R switch.

But... the fact it reads DCV so close indicates to me the internal reference voltage is pretty close to dead nuts... that means everything else can be made right.

EDIT: I took a quick look inside, but found no obvious simple culprit. Will need to do some live percussive diag when I have time, but RIFAs lurking under the GPIB connector and power switch are visibly crazed, so I'm probably going to back-burner this until replacements can be installed.

mnem
*ZZZzzzZZZzzzZZZzzz...*

[mnementh]

https://youtu.be/LikxFZZO2sk

Fuggin' a-diddy!

Atlas has come a long way since I saw him fumbling around in the woods a few years ago. This is serious machine learning.

https://youtu.be/8vIT2da6N_o

mnem
*Toddlers off to ded*

[URI]

Shi*... Shi*... Shi*... Where the FU** IS IT?!?





 Oh... okay... there it is...

It's not packed like Keysight wanted it to be (they don't like bubble wrap, they call it californian air -never heard of that term), but from a practical point of view it's packed very well and should be fine -distance between device and the outer cardboard package looked decent to me.   

Ah, the link to the Keysight packaging guide (german): LINK 

[Berni]

The "californian air" they show in that PDF are those big plastic air filled pillows. Those indeed are shit. As soon as they meet anything remotely sharp they will puncture and deflate, turning into a useless piece of plastic foil that wouldn't protect a damn thing. Also if the box with a heavy boat anchor is dropped onto one it can probably create enough pressure inside to explode it. Even crumpled up newspaper would be better than this (But please don't, paper is also near useless).

Bubble wrap is a lot tougher and will take a lot of abuse before it pops(Especially the more high quality one) and if it does pop it only looses one little bubble, the rest around is still perfectly functional.Im perfectly happy to get a boatanchor wrapped in a mountain of bubble wrap. Tho i still prefer foam blocks around it + the bubble wrap.

Nice PDF there! I wish more ebay seller would read it.

[bd139]

Just a heads up for anyone with a 3478a. If you do replace the RIFA don’t try and take the extender bar off the power switch. Unscrew the switch and pull the whole thing out. They are brittle as feck! Yes I broke the switch. 

Had to epoxy and pin it.