Test Equipment Anonymous (TEA) group therapy thread

[Neomys Sapiens]

mnem
*rubs hole in index finger thoughtfully from where the Oldaker test probes bit me... again*

See? They don't even do you any good!

[factory]

Why is the engineer any better than the generic cheapies?

I've got a Soldapullt, which is bit like a reverse air pistol, and a couple of cheapies and I usually use the cheapies because they are smaller. I also had a desoldering iron with a one shot pump, but I found that was useless.

I've always found solder pumps a bit hit and miss, sometimes they work like magic and sometimes they don't.

Yeah that's the problem I had. But most of the time they didn't work and you ended up knackering something in the process.

Good video here where one actually works 

https://youtu.be/WyiA4Giw5IM?t=295

Actually worth watching for any Tek fans as well.

Nah, according to some folk here that is pure crap because that engineer uses the Paul Carlson method of removing components from the mother board. Wrench parts off like can so they say damage pads and tracks etc 

Yeeaahh... still made me fucking cringe. 

I mean, I know it's beefy old-school FR4 and TH construction, so should be able to stand the abuse... but too many "marginal" PCBs over the years weakened by heat and cap electrolyte have taught me to never trust that you can get away with abusing a PCB Magilla G'rilla style.

I positively loathe having to do trace repair; doubly so when it's as a result of my own carelessness.

mnem

How about trace repair on a Toyota Supra ECU? 90's Toyota ECU's were right in the thick of the capacitor plague. I've repaired heaps of these things....
Not only did I have to clean and repair the board, I had to undo the halfarsed previous attempt at repair carried out by a gorilla...

The owner reported that the car ran beautifully afterwards. 

That seems to be a common problem with some 80's & 90's ECUs, Shango066 has done a couple of videos on them. I find the same leaking caps in stuff at work, Panasonic HF series I think, usually all the same value are found peeing electrolyte, can get under the conformal coating too & eat the traces.

David

[bd139]

Also why you tend not to find electrolytic capacitors used at all in certain sectors.

Curious Marc note here  https://youtu.be/9fGurEa3EVk?t=907

[Robert763]

What is this and is it of any use to man or beast?

BK Precision 541 component comparator...

https://www.ebay-kleinanzeigen.de/s-anzeige/component-comparator-541/2186659541-172-952

Looks like a very basic curve tracer add-on for comparison of multi-pin devices, to compare a unknown/faulty part against a know good part. We had a 386 PC at work with a similar component tracer ISA card built in, we never used the sockets for connecting to multi-pin devices, or circuit board connectors.
https://worldradiohistory.com/hd2/IDX-Consumer/Archive-Radio-Electronics-IDX/IDX/80s/1987/Radio-Electronics-1987-12-OCR-Page-0005.pdf

David

No, your datasheet says it's intended to be used with the 540 component tester... So I'd guess it's an automated switching network allowing you to compare the curve tracer's output against a new known-good IC one leg at a time.

mnem
 

Err, no guys.
Read the description above the picture. The 541 is a LOGIC comparator not a curve tracer. It allows you to set up and/or monitor a number of pins (20 acording to advert) on a pair of TTL or CMOS chips and compare the two chips. looks like it has a clock generator too.    

[factory]

What is this and is it of any use to man or beast?

BK Precision 541 component comparator...

https://www.ebay-kleinanzeigen.de/s-anzeige/component-comparator-541/2186659541-172-952

Looks like a very basic curve tracer add-on for comparison of multi-pin devices, to compare a unknown/faulty part against a know good part. We had a 386 PC at work with a similar component tracer ISA card built in, we never used the sockets for connecting to multi-pin devices, or circuit board connectors.
https://worldradiohistory.com/hd2/IDX-Consumer/Archive-Radio-Electronics-IDX/IDX/80s/1987/Radio-Electronics-1987-12-OCR-Page-0005.pdf

David

No, your datasheet says it's intended to be used with the 540 component tester... So I'd guess it's an automated switching network allowing you to compare the curve tracer's output against a new known-good IC one leg at a time.

mnem
 

Err, no guys.
Read the description above the picture. The 541 is a LOGIC comparator not a curve tracer. It allows you to set up and/or monitor a number of pins (20 acording to advert) on a pair of TTL or CMOS chips and compare the two chips. looks like it has a clock generator too.

I doubt it's more than a bunches of switches, the octopus type output can be switched, to use the component, or an XY scope to view the patterns, it would still require manual viewing of the patterns, one at a time.
The rate control is for the speed it switches between the two channels.

The ISA card at work used a bunches of reed relays and the software could automate the process against saved patterns, or could be used manually by viewing the two patterns at once (different colours for the two channels). It was very hit & miss with some board/circuits, i.e. not always helpful, as the difference was not clear enough.

These are used with boards/devices/components that are powered off only.

I think you may have got confused with the advert, the description of the 541 is below the picture, the bit above is for the two handheld devices in the picture on the right.

David

[Specmaster]

And continuing the theme....

Today I shall be mostly standing around at Southend-on-Sea airport snatching the odd photo of the miiltary hardware that is using it as a temporary base for the Eastbourne 4 day airshow. This will be a repeat of what I mostly did yesterday 

[Robert763]

What is this and is it of any use to man or beast?

BK Precision 541 component comparator...

https://www.ebay-kleinanzeigen.de/s-anzeige/component-comparator-541/2186659541-172-952

Looks like a very basic curve tracer add-on for comparison of multi-pin devices, to compare a unknown/faulty part against a know good part. We had a 386 PC at work with a similar component tracer ISA card built in, we never used the sockets for connecting to multi-pin devices, or circuit board connectors.
https://worldradiohistory.com/hd2/IDX-Consumer/Archive-Radio-Electronics-IDX/IDX/80s/1987/Radio-Electronics-1987-12-OCR-Page-0005.pdf

David

No, your datasheet says it's intended to be used with the 540 component tester... So I'd guess it's an automated switching network allowing you to compare the curve tracer's output against a new known-good IC one leg at a time.

mnem
 

Err, no guys.
Read the description above the picture. The 541 is a LOGIC comparator not a curve tracer. It allows you to set up and/or monitor a number of pins (20 acording to advert) on a pair of TTL or CMOS chips and compare the two chips. looks like it has a clock generator too.

I doubt it's more than a bunches of switches, the octopus type output can be switched, to use the component, or an XY scope to view the patterns, it would still require manual viewing of the patterns, one at a time.
The rate control is for the speed it switches between the two channels.

The ISA card at work used a bunches of reed relays and the software could automate the process against saved patterns, or could be used manually by viewing the two patterns at once (different colours for the two channels). It was very hit & miss with some board/circuits, i.e. not always helpful, as the difference was not clear enough.

These are used with boards/devices/components that are powered off only.

David

Doh! I read it wrong     
Looks like it is a combination logic comparator and multiplexer for a curve tracer.

[Specmaster]

@factory.

Thanks for your PM yesterday, I shall respond later over the weekend via PayPal, and once again thank you for your kind assistance with regard to the power supply.

[m k]

Since heat exchange was the issue.

[Saskia]

trying to align the 4 free standing mounts to get a parallelogram that is tilted at 35 degrees and has a weight of a quarter ton. my back hurtz

[factory]

HP 404A battery operated vacuum bulb voltmeter update.

Previously I had repaired the panel meter and installed D size batteries leak-tubes for the vacuum bulb heaters.

I've tested the panel meter, F.S.D. should be 1mA, it reads a little low, not surprizing given the abuse it had suffered.


As I didn't have the required 45V batteries, or 15 PP3s, I had to use the HP 711A to provide the HT of 135V, a tap on the original batteries would have provided 122.5V, I used a 22V zener diode in place of this.
With the original batteries it would have run for around 60hrs, before they would all need replacing.



I bought the HT up slowly to 135V, the peak current draw was about 15mA, this has since dropped a lot lower after being run for a while.

Then I switch everything off, while I went back in the house, after returning the HP 711A was misbehaving and blowing those crappy RS fuses, blew the last three of those  , then remembered I had bought some older Littlefuse fuses after this happened before and yes I went through the 711A troubleshooting guide, no problems were found, I suspect it's a transformer inrush current problem, the first Littlefuse fuse worked fine. 


The 404A is working OK, a couple of the Sprague wax paper grid coupling capacitors were showing a little leakage (C10 & C17), after replacing those the leakage was gone, C8 seems OK, probably due to the lower voltage.
The free pdf manual is for a later serial number and has an extra capacitor C23 (0.047uF) in parallel with C10 (0.22uF), these are listed as 600V, but mine had a 0.25uF at 200V, it looked original.



Still to do, replace C1 (0.05uF) as it's the input capacitor, should be rated for 600V according to the parts list and take some more pictures, as I have none of the tag strips & range switch. 

David

[Squarewave]

Now at 56 c/kWh. This is bloody insane.

Do you pay hourly rate or is it a generic high level? The peak prices were around those levels today, or even a bit higher, in SE4, the southernmost part of Sweden. Thankfully, we're in SE3, which is a little bit cheaper. (source: Nordpool)

I'm very much on the fence as to how I'm going to tackle next 12-month period; which agreement model I'm choosing, fixed, semi-rigid or full-floating. Full-floating requires instrumentation and some consumer control too. Tempting but do I have the drive to fix it what with the other 100s of things I need to do?  As someone wrote; "The dream of renewables in Germany mostly was natural gas through NordStream..."

Topic discussion: Old TE is energy inefficient. Having large power costs influences the Addiction. Besides, electricity is sort of on-topic.  I hope.

One thing I've heard in audio circles quite frequently is people who have tube amplifiers doing a seasonal changeout and running solid state equipment over the summer to avoid doubling up on electricity to run the equipment and then running the air conditioning more to remove the heat it generates.  I've done that myself and avoided running boatanchor test equipment during the summer for the same reason.  I don't know if this is a thing with ham radio operators and if the ones who have and use tube equipment substitute solid state when it's hot out.

The natural gas bill showed up today and the equal billing payments are 35.3% higher year over year.  What this does to hydro rates in terms of the effects it has on electricity prices due to the portion generated at natural gas fired power plants probably won't be known until late October when the time of use schedule changes and rates for the next six month block are announced.  If electricity prices get out of hand, when, how, and with what equipment the workshop gets run with is going to be up for review.  We'll see what happens.

I run a chewb radio in the summer too, the heat doesn't bother me, it doesn't get hot enough here. Highest this year was 40c maybe. My radio room has massive french doors and velux windows anyway, so plenty of ventilation.

[Per Hansson]

Thank you so much for the link, just like you I had seen only the first episode but got a bit put off by it, now I watched the rest and they where quite good!
They did achieve one other thing for me: I'm totally put off buying a vacuum tube oscilloscope after seeing all that, I would not have the patience to repair such a beast!

On the contrary. There is nothing more satisfying than to transform this....



Into this....

Oh don't get me wrong, I totally agree!
But when it comes to having to troubleshoot a hundred vacuum tube valves vs a couple MOSFET's I prefer the latter is all I'm saying
Don't think I've posted this before, I do have a couple valve based devices even though they where long out of production before I was born

[m k]

New caps are like out of their league.

[Zenith]

Oh don't get me wrong, I totally agree!
But when it comes to having to troubleshoot a hundred vacuum tube valves vs a couple MOSFET's I prefer the latter is all I'm saying
Don't think I've posted this before, I do have a couple valve based devices even though they where long out of production before I was born

Only scopes like the Tek 500 series have a hundred valves.

A lot of valve scopes, that were respectable instruments in their day, such as the Solartron CD1400, have more like 20 valves. When sorted out, they are still usable scopes for a lot of things.

Then there are the boatanchor radios, but few of those have more than 20 valves.

The vintage solid state stuff can have its own frustrations, such as special ICs or hybrid circuits that are unobtainable or very expensive. Some transistors that used to be common can be trouble to track down.

[TERRA Operative]

It's alive!

After languishing in the 'to-get-back-to' pile for literally years, I finally put the HP 5340A 18GHz frequency counter back together.

And
It
Works!!!

I was worries that the front-ends for the 50Ohm input might have been popped as they are a bit delicate but they seem to be fine.
Apparently there was an upgrade kit that HP released that replaced the modules with ones that were more robust, but I can only dream of finding a set....

I bought a few scrap units (like literally scrap) for parts, and managed to get my hands on the transformer for the optional OCXO, I've also designed a PSU PCB too, so all I need is a 10544A OCXO and I'm all set there.

I've combined all the best and latest revision parts that I have in stock into this unit, so it should hopefully work well.

Next step is to tweak a couple things, then start calibrating and adjusting it.... (Luckily I also made extender cards and test fixtures etc).

[McBryce]

Anyone in the UK with a serious amount of HP gear to diagnose? Here's someone (not me) selling almost every HP card extender you could think of: https://www.ebay.co.uk/sch/emjo_90/m.html?item=314114703504&rt=nc&_trksid=p2047675.m3561.l2562

McBryce.

[factory]

The one incorrectly labelled 08640-60033, is already fitted to all HP 8640B (actually 08640-60022, A10A3), it's not an extender, it's a riser card and actually gets removed, to position the board vertically for testing/servicing, not worth £40. 

David

[BU508A]

The one incorrectly labelled 08640-60033, is already fitted to all HP 8640B (actually 08640-60022, A10A3), it's not an extender, it's a riser card and actually gets removed, to position the board vertically for testing/servicing, not worth £40. 

David

One can give it a try. It's like fishing: someone will bite, it's just a matter of time.

[bd139]

The one incorrectly labelled 08640-60033, is already fitted to all HP 8640B (actually 08640-60022, A10A3), it's not an extender, it's a riser card and actually gets removed, to position the board vertically for testing/servicing, not worth £40. 

David

That was pretty standard for HP stuff. There’s was a riser in the 3776A in the end slot.

[BU508A]

Yeah it’s weird. It’s definitely NPN. I buzzed out a few with diode tester. All the same. These are TI 1970 stamped ones. Will see if there’s a catalogue on bitsavers…

I suppose it’s a good excuse to buy a DCA55 or something 

Could it be a counterfeit part?

I think this was just a Friday afternoon labelling job and murphy doing his thing to me today by handing me the one duff one to play with . I tested all the others and they are all PNP. Just one part was wrong. It does work quite happily as a dual NPN transistor though!

Obviously you should widlarize any parts which can screw with you later so I chopped the top off with some cable cutters.



Fun fun fun.

Would have responded earlier.
It's a pity, that you've cracked open it.
Would have sent it instead together with a real PNP one to user Noopy.
He is the owner of the website Richi's Lab so he could take some pictures of both and compare them.
Could have been interesting.

[factory]

The one incorrectly labelled 08640-60033, is already fitted to all HP 8640B (actually 08640-60022, A10A3), it's not an extender, it's a riser card and actually gets removed, to position the board vertically for testing/servicing, not worth £40. 

David

One can give it a try. It's like fishing: someone will bite, it's just a matter of time.

Yes got caught with some extenders for a 1425A timebase, then later bought the modules they go with and a set of three were fitted.  Might not be supplied with the early ones though. Got some spare boards from the same seller and found they had robbed all the tunnel diodes. 





bd the 08640-00022 riser card is not an extender, it's fitted in normal operation, I checked the manual to stop me wasting money on one and qservice have it for less including shipping, no I don't want it either.

David

[factory]

Yeah it’s weird. It’s definitely NPN. I buzzed out a few with diode tester. All the same. These are TI 1970 stamped ones. Will see if there’s a catalogue on bitsavers…

I suppose it’s a good excuse to buy a DCA55 or something 

Could it be a counterfeit part?

I think this was just a Friday afternoon labelling job and murphy doing his thing to me today by handing me the one duff one to play with . I tested all the others and they are all PNP. Just one part was wrong. It does work quite happily as a dual NPN transistor though!

Obviously you should widlarize any parts which can screw with you later so I chopped the top off with some cable cutters.



Fun fun fun.

Would have responded earlier.
It's a pity, that you've cracked open it.
Would have sent it instead together with a real PNP one to user Noopy.
He is the owner of the website Richi's Lab so he could take some pictures of both and compare them.
Could have been interesting.

That incorrectly labelled 2N3347 dual trannystor, could have been from 2N2639 to 2N2644, the complementary NPN versions.

David

[mnementh]

Currently doing the family time thing at the Hartford Science Center.

Have not yet had to eat any children, but the day is young.   

mnem

[mnementh]

mnem
*rubs hole in index finger thoughtfully from where the Oldaker test probes bit me... again*

See? They don't even do you any good!

LOL... 

I'd say anything that makes a tinkerdwagon stop and think for a moment is probably a good thing. 

mnem