Test Equipment Anonymous (TEA) group therapy thread

[Martin.M]

Here's the Vertical Amplifier after cleaning. The brown crap on the chassis was a dried liquid so I had to resort to using a liquid cleaner to remove it.




Lots more to go. 

535A 

1.) remove the tubes and put them on an styropor, so each tube will go back in its orinally place.
2.) remove the HV board and clean the HV board dry, with Q Tips or like that.
3.) to protect with plastik foil: the both electrolytics with paper jacket and the mains transformer.
4.) get the gun    Windows Cleaner Flid, 3-2-1- fire ! The liquid will flood out the dust. Some help with little brush, Q Tips between the parts in the solding stripes.
5.) clean the tubes dry, windows cleaner will remove the type stamps on them. Then put them back in the clean scope.
6.) put back the HV board.
7.) let it be, one day in a warm place for drying.

continue with test + repairs.

when it`s done continue : https://www.wellenkino.de/cleaning

[bd139]

On the subject of boat anchors, BOAT ANCHOR ALERT!

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F264580364285

And no I’m not buying it 

[Martin.M]

585A is the fast 100MHz tube Tek.
The plugins are not compatible to the other 500 series Tek,
but the is a  adaptor to use them all in the 585A.
It runs only ±2div. The CRT includes a part of the delaylines and a group of 16 vertical deflection plates to get enough acceleration.
Very collectible 

my 585A is the serial No 15 made in heerenveen NL.

[Martin.M]

the little 213 killed again the 3.3nF in the charger PSU. 
written is: 600VDC, used was: 1kV (RIP) the spare is the same.
A 2kV may be too large to pass in the little metal box.
done.

[med6753]

535A 

1.) remove the tubes and put them on an styropor, so each tube will go back in its orinally place.
2.) remove the HV board and clean the HV board dry, with Q Tips or like that.
3.) to protect with plastik foil: the both electrolytics with paper jacket and the mains transformer.
4.) get the gun    Windows Cleaner Flid, 3-2-1- fire ! The liquid will flood out the dust. Some help with little brush, Q Tips between the parts in the solding stripes.
5.) clean the tubes dry, windows cleaner will remove the type stamps on them. Then put them back in the clean scope.
6.) put back the HV board.
7.) let it be, one day in a warm place for drying.

continue with test + repairs.

when it`s done continue : https://www.wellenkino.de/cleaning

(Attachment Link)

(Attachment Link)

(Attachment Link)

Martin, I would love to do that but it has too much "Murphy" written all over it and I'm afraid he'll come and camp out long term. 

[med6753]

On the subject of boat anchors, BOAT ANCHOR ALERT!

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F264580364285

And no I’m not buying it 

That's a decent price. 

Edit...you're building a bigger bench. Go for it! 

[bd139]

Doesn’t need a bench. 

Seriously though, I wish I could but need to avoid large arrivals at the moment.

[mansaxel]

May attempt duck again tomorrow.

It is scheduled for new years eve here. Pretty much the recipe I wrote upthread, and I've got two bottles of 2017 Chateau Melin Pinot Noir to go with it.

[mnementh]

   the little 213 killed again the 3.3nF in the charger PSU.  written is: 600VDC, used was: 1kV (RIP) the spare is the same. A 2kV may be too large to pass in the little metal box. done.

Martin, you have the neatest toys. Just watch out med doesn't come mug you for that smurf-sized little beastie. 

mnem
*tzzzt*

[mnementh]

535A 

1.) remove the tubes and put them on an styropor, so each tube will go back in its orinally place.
2.) remove the HV board and clean the HV board dry, with Q Tips or like that.
3.) to protect with plastik foil: the both electrolytics with paper jacket and the mains transformer.
4.) get the gun    Windows Cleaner Flid, 3-2-1- fire ! The liquid will flood out the dust. Some help with little brush, Q Tips between the parts in the solding stripes.
5.) clean the tubes dry, windows cleaner will remove the type stamps on them. Then put them back in the clean scope.
6.) put back the HV board.
7.) let it be, one day in a warm place for drying.

continue with test + repairs.   when it`s done continue : https://www.wellenkino.de/cleaning

Martin, I would love to do that but it has too much "Murphy" written all over it and I'm afraid he'll come and camp out long term. 

   https://www.amazon.com/Grip-Industrial-Assortment-Electrical-Cleaning/dp/B079J64P7B/

Awww, come on buddy... be brave!!! 

mnem
Yes, you may touch it.

[capt bullshot]

Done fixing these two guys:

Both of them were victims of the capacitor plague, still some self test failures left after replacing all the SMT electrolytic caps.

Left hand one had a stable Acquisition board fail (delayed trigger doesn't work), otherwise OK. Fixed by removing and re-soldering the trigger select / comparator chip 

Right hand one had some intermittent Acq. failure (missing samples in ETS mode, Ramp doesn't end self test message). Fixed by replacing a SMT transistor (which most probably wasn't bad at all), and one more thoroughly board cleaning run.

Congrats! How long did that take? Lots of caps from what I recall.

Anyway, now they're working again, what do one want to do with TDS420's? Anyone to know if one can hack them to 460's?

Second one still dead, didn't start investigating the failure yet.
Thanks to madao, I've turned the first one into a TDS460 and enabled the Video Trigger and Advanced Math (FFT) options. Field adjustment SW works, but didn't change anything noticable (I did expect somewhat smaller overshoot from the HF cal).

Replacing the caps and cleaning the boards took quite a while (maybe 2 hours per scope), finding the trigger fault as well, recalibration using the Field Adjust SW also is a lengthy job for the HF cal part.

[worsthorse]

the little 213 killed again the 3.3nF in the charger PSU. 
written is: 600VDC, used was: 1kV (RIP) the spare is the same.
A 2kV may be too large to pass in the little metal box.
done.

(Attachment Link)

I must have missed something. What is that? It looks very cool.

[Specmaster]

Looking good. If only if known a few days ago. Just got rapid delivery this afternoon.   

Power supply looks pretty good. Definitely no nasty issues from what I can see.

Just got back from actual shopping and am now considering Dignitas.

Nah, don't do it, we'd all miss our London buddy badly, you know that. Rapid order is in, I bit the bullet, my OCD part of me snapped into place and made me do it, it would drive me up the wall looking at it and wondering just where in the scale things was the fine pot positioned.  I'm loving the DC load switch, it avoids any overshoot and also allows for easy current limit adjustment. I have to say however that the cheaper Chinese power supply I'm retaining has finer adjustments on both current and voltage.

Don't worry - post shopping depression has worn off now

Yeah the output switch is the best feature on them. A step above all the other vendors of the era who didn't bother with output switches. Makes it considerably easier to set up, particularly in lab environments. Talking of which, they used those supplies at NPL for clock subsystem power  . Think they used later rev ones similar to my PL330QMD for the cesium fountain clock stuff.

Looking like I'll have to live with the slight discrepancy on the actual voltage compared to the indicated one on the display because all the downloadable manuals refer to the newer version of the unit and the various trimmers are in different locations so any attempt to calibrate it might make it considerably worse. 

Was shopping so bad then? I went food shopping today but admittedly, I was outside the shop at 7:50am waiting for them to open the doors and it was very quiet, a dozen of us having the entire supermarket to ourselves. All done and dusted within 30 minutes.  

[bd139]

Just twiddle them all until it’s right 

Shopping was terrible. I went stuff shopping in Kingston and figured I’d hit the supermarket there. They had sod all in. So I had to go back via Tesco at Twickenham and it’s a rugby day which means it’s fucking crawling. Next time I walk. Easier!

[Specmaster]

Haha, SWMBO doesn't believe me when I come back with certain items missing from our weekly shop for the first few weeks after crimbo. I'm not sure whether its down to the shops not placing orders in time or if it's the producers unable to get certain key ingredients from their suppliers or whatever. What I do know is that sometimes even the most basic of things can be hard to locate for a while.

Call me chicken if you like, but I'll leave the calibration alone till I can find the correct fecking manual, I've had way to many scopes in my time when someone has done that twiddled them all approach and futzed everything up. Besides the actual current is spot on and so its best left untouched, nothing I do with it will be that fussed over getting up to 30mV over voltage thats for sure 

[capt bullshot]

Anyway, now they're working again, what do one want to do with TDS420's? Anyone to know if one can hack them to 460's?

Second one still dead, didn't start investigating the failure yet.

As guessed, the main SMPS transistor was shorted out. Replaced BU508A with something similar at had at hand, now it's up and running again (no matter, I did replace the other ones SMPS transistor the same way some time ago and it worked out fine).



Power consumption looks normal:



Modified one channel to TDS 460 BW, just to see the difference - yes it's worse than the freshly recalibrated other one, so I've to do another full calibration run.

[capt bullshot]

Modified one channel to TDS 460 BW, just to see the difference - yes it's worse than the freshly recalibrated other one, so I've to do another full calibration run.

Finished, doesn't look too different, but slightly notable (it's a tiny bit more flattened). If one didn't know the difference, one wouldn't notice. I'm somewhat disappointed for that little effect after one hour calibration run.

First picture shows TDS420 trace (Ref 1, quite flat) and uncal'd TDS460 trace (CH1, rise time measurement):


Now after the calibration run:


So IMO, it's not absolutely necessary to do the HF cal after hacking a TDS420 to TDS460.

[mnementh]

So what's the plan...? After using both a reasonable time to make sure no new gremlins manifest, send one down the road to pay for both of 'em...? Or do you really have need for 8 channels of that kind of bandwidth...? 

mnem
*Current mood: Tangential*

[mnementh]

*Peeks in on video card prices to see how things have shaken out since my build*   Holy fucking asscrackers... have you gamers all lost your pixel-raping minds...? 

  are y'all gonna do when AMD finally releases the RX5800-RX5900 series...?

mnem
  *SMH*

[_Wim_]

For static-sensitive gear, I'll usually wash the brush beforehand/dry on a towel and periodically during use to ensure it discharges through my body to the equipment chassis or ground-strap on my wrist. 

Look for "ESD Brush" on Ali-express. Lots of types available for only a few dollar. They are static dissipative, so when you are wearing a wrist wrap, they cannot accumulate any charge. Also very nice to remove flux from pcbs (use a different set for that off course)

[capt bullshot]

So what's the plan...? After using both a reasonable time to make sure no new gremlins manifest, send one down the road to pay for both of 'em...? Or do you really have need for 8 channels of that kind of bandwidth...? 

TBH, I've done this just because I can and I wanted to and they were free. I've got way more useful scopes than these, so ATM I'll just stash them back. Don't know what to do with them now. Anyway, I've productively used a setup of two 4ch scopes before, just to have two independent timebases like the old boat anchor dual beam CROs.

[tggzzz]

I went stuff shopping in Kingston and figured I’d hit the supermarket there.

The last time I was taken shopping in Kingston, supermarkets were novel and small, and there was a horse butcher somewhere in the triangle by the "Kingston historic market".

It may be relevant that a nearby road is called "Horse Fair", and has been since time immemorial.

[bd139]

I went stuff shopping in Kingston and figured I’d hit the supermarket there.

The last time I was taken shopping in Kingston, supermarkets were novel and small, and there was a horse butcher somewhere in the triangle by the "Kingston historic market".

It may be relevant that a nearby road is called "Horse Fair", and has been since time immemorial.

Ah yes. Horse Fair is still there. However now it’s beat boxing buskers, some toppled phone boxes, lots of ridiculous smelling people, humans dogems staring into the abyss of WhatsApp and rampant consumerist debt being generated. Ugh.

Apparently my miserablefuckeritis is a day late 

eBay dead still. Boo hiss.

[tggzzz]

I went stuff shopping in Kingston and figured I’d hit the supermarket there.

The last time I was taken shopping in Kingston, supermarkets were novel and small, and there was a horse butcher somewhere in the triangle by the "Kingston historic market".

It may be relevant that a nearby road is called "Horse Fair", and has been since time immemorial.

Ah yes. Horse Fair is still there. However now it’s beat boxing buskers, some toppled phone boxes, lots of ridiculous smelling people, humans dogems staring into the abyss of WhatsApp and rampant consumerist debt being generated. Ugh.

When I was (too) familiar with Kingston, the A307/A308/Clarence St and bit between Bentalls and the (non-existant) John Lewis was a one-way "roundabout". John Lewis was a car park, and that part of the Horse Fair a minor side road.

More entertainingly the Bentalls window panes were a yard deep, being heavily curved to that there were no reflections obscuring the goods on sale.

I'd mutter "Ah, happy times", but shopping was always involved.

I did enjoy my father taking me to look into the boilers in Kingston power station and the enormous piles of coal, though. Only time I've seen something similar as an adult is looking into the boilers in Stretham Old Engine. The people that built and operated those engines must have been regarded with awe.

Apparently my miserablefuckeritis is a day late 

It is never too late

[beanflying]

*Peeks in on video card prices to see how things have shaken out since my build*   Holy fucking asscrackers... have you gamers all lost your pixel-raping minds...? 

  are y'all gonna do when AMD finally releases the RX5800-RX5900 series...?

mnem
  *SMH*

Very happy with my Gigabyte 5700XT nice and quiet even on hot days under stress and scored it locally for a good deal. Unless I become a total gamer or wannabe '4K is an ESSENTIAL to my work/life' dick:palm: this has more poke than I will need for the next 3-5 years+