Test Equipment Anonymous (TEA) group therapy thread

[Vince]

Oh yes, my friend who got me to go pick-up this Tek scope... this morning over the phone he told me about it ! 
He used them a few times.

I guess someone local to Sphere will go collect lots of stuff and then it will appear soon for sale on Ebay, bit by bit...

I wish I had an A330 private cargo plane to go pick everything up ! 

[EggertEnjoyer123]

It seems like a full truckload from Canada to the US costs about $2,000 (https://www.freightera.com/blog/full-truckload-cross-border-freight-shipping-rates/)

If there's 50 interested people who live in the same area, you could arrange to pay $40 for 2% of a truck, which is still a pretty big volume.

[Vince]

I guess though that it would be a nightmare to figure out how to fill the paperwork to export all that to the US.... would have to detail every single item, for the customs to figure out how much to bill the importer...

Unless the US and Canada have special agreement where you cna move stuff across the border freely, like we do here between countries in the European union.

[factory]

OK I managed to get the test pattern, here it is....

Confirms the problems I found earlier, but at least now it's better evidenced.

1) the rotation,
2) the focus problem where only a central vertical band is in focus, and nothing else
3) distortion.

That is what I thought it would display, the almost perfect trapezoid shape makes me think it's a fault with the adjustment circuits or supply and not the CRT, hopefully your friend will be able to fix it.

David

[Vince]

Oh great that's good news indeed, may you be right ! 

That would b so cool he he could fix it !

He always wanted one so badly, so if he can get it working, he would get his dream come true for only 20 Euros !

... and the I wold be so happy to have made this possible, being local to this scope.
That will be a little thank you for all the TE and stuff he gave to me a few years back ! 

As for me, I guess some day I will find one as well.
In the mean time I have plenty of other TE to fix and restore to keep me busy and make me happy.

[factory]

And a Tek THM565 distraction appeared on the ePay last weekend, I couldn't stop myself from making an offer, which was accepted.   
The bad news was the seller mentioned it didn't power up, I already knew that the expensive PSU ICs can be damaged if you power it up and the capacitors have pissed conductive electrolyte all over the PCB. 

It arrived a couple of days ago, I took it apart straight away and got the six SMD capacitors removed, the four PSU ones were just starting to pee, the two on the other board had visible leakage before removal.









Some temporary through-hole caps were fitted for testing, to find out if I need to order the LTC1174 ICs (these need to be the adjustable version if anyone has to replace them), thankfully both voltages were correct, these ICs were probably saved by the corrosion to the battery holder, it was making very poor contact and hardly any voltage was getting to the mainboard. 





I've removed my bodge caps & reassembled it and will add some proper replacements to my next Mouser order, along with some caps for a mid 90s laptop I'm trying to resurrect.

David

[Vince]

Oh I didn't know about these things, they are so cute, I want one now ! 

[wkb]

Interesting piece of Tek kit. Literally never saw one of those here 'in the wild'. Here being in the Netherlands.

Just missed a Fluke PM3088A scope, offered for free due to a broken PSU 

Wilko

[factory]

They seem to have been made with custom firmware for vehicle repair too, the Mac Tools ET2020 is one version, not much on Tek wiki for rebrands, I've no idea how many other brands there are.

https://www.eevblog.com/forum/testgear/tektronix-thm56x-portable-scope-hackteardowndiscussion/

I didn't copy Shango066 and use brake cleaner , he made the expensive mistake of ordering the wrong variant of the LTC1174 DC/DC converter IC too.



David

[TERRA Operative]

I've seen a couple of these pop up on Yahoo Auctions in the last few months. Always went for a little more than my impulse buy threshold..

I want to play with one, but do they offer anything that a THS720 doesn't? They seem to be a logging/graphing multimeter?

[oz2cpu]

my latest test equipment :-)
Russian X1-7B Oscilloscope and Spectrum Analyzer 1978
no kidding, they merged a scope and spectrum and tracking gen into one compact unit in 1978

it is full of wheel, gears, strings and springs
I also released a video I hope you enjoy
https://youtu.be/n-fbSL3BTiU

it is really wierd and strange to use :-)
in all modes actually, maybe some of the challenge is the text on all knobs,
I feel my translater did a good job.

[factory]

I've seen a couple of these pop up on Yahoo Auctions in the last few months. Always went for a little more than my impulse buy threshold..

I want to play with one, but do they offer anything that a THS720 doesn't? They seem to be a logging/graphing multimeter?

The THM550/560/565 predate the THS series as far as I can tell, there was a little Tektools brochure in the box with my THM565, it has the trio of THM TekMeter scopes and has the much higher spec 222/224 DSOs on another page, it also has a selection of DMMs.

The THM5xx have the same MAX134CQH multimeter IC as the THS7xx series, but the scope part of the THM5xx is only good for up to 5MHz at 25MS/s, terrible compared with the THS, the THM550 only has one scope channel, the THM560 & THM565 have two scope channels, inputs are all shrouded banana sockets, so no plastic covered BNCs to get chewed up, it also uses standard AA leaktubes.

The 560 adds electrical related tests for; line, 3-phase, current, power factor (with current probe) and transformer harmonic derating factor (with current probe). The 565 adds; an event clock, extra save memory, the LCD backlight (EL type) and a motor test.

For some odd reason most of these THM are advertised at crazy high prices, i.e. the same or often more than a THS series.  I can't understand why.

The THM571 seems to be the same as the Mac Tools ET2020, with vehicle related tests.
Others mentioned in this manual are THM570, THM570U and THM575, these also have automotive tests, the 575 has menus in other languages (doesn't say which).

https://xdevs.com/doc/Tektronix/pub/TEK%20Benchtest%20Instruments%20%26%20Handheld%20O-scopes%20Basic%20Service%20Technical%20Reference.pdf

The casing seems to be reused on a telecoms related TDR too, sold as the Greenlee or Tempo TelScout TS90, the input board must be quite different, no idea if there are any others.

David

[Ero-Shan]

Yesterday I built myself a new toy. I wanted this since long, but was never happy with any idea I had regarding the actual design.
Giving up on the goal to produce the perfect dim-bulb tester, the task became somewhat easier. Everything went fine for a while, until I butchered the hole for the C14 plug. I had totally forgotten that the radius on its edges was 5 mm, not 10 mm as at the C13's connector. I just can't get anything done without one of these snafus. At least this is on the back side and does not really impair the function. The switches are also not 100 % perfectly parallel, but that is not too noticeable, so I don't care. At least the contraption worked perfectly the first time!

As it is written: »Thou shalt give a name to every thing thy have created«, I think I will call it Model 9204. Don't ask.


[ Specified attachment is not available ]

[m k]

I bought a LED, 0.1W 250-260um UV-C type with 20mm copper base.
Tested its threshold voltage and then dimmed it considerably by using it a moment without a shunt resistor, current was >10x and it wasn't intentional.
Actually dimming is a guess, based on a missing visible brightness, but anyway, it's still just fine EPROM eraser.
This one is without a light angle info but I guess 120 degrees is better than 60, no internal protection info either.

I used 150ohm resistor that happened to be on the table, for curious souls it's a 25W metal case model.
Threshold voltage was 5.7V so 2.5V over the resistor give just a bit below 0.1W, pretty fine for possible 9V battery use.

I think I'll put 6V zener over the LED for protection and use one of those mini regulator modules for main voltage.
Blank check needs many pins, Arduino is a bit thin so STM Blue Pill then.
Few demo erasures indicate that half an hour is plenty.

Demo chips were TMS27C256-1JL.
First bits started flipping after few minutes and majority of bits were flipped in few minutes.
Within few minutes only few stickies were still down, last one flipped after around 7 minutes.
Still blank over night and without extra blanking time.

I think I'll add a hinged LED installation.
Quick check couldn't see any 0.1" spaced hinges.

[bad pictures rejected]

[Neomys Sapiens]

Oh I didn't know about these things, they are so cute, I want one now ! 

I can offer a fully working THM560 (AC PSU module only, no battery pack; no accessories) in exchange for a fully working Tektronix DMM916, DMM870 or TX3 hand multimeter (must have holster, DMM916 preferred). I would even cover both sides of shipping. If the DMM is really fine, I would might in some accessories.

[TERRA Operative]

I bought a LED, 0.1W 250-260um UV-C type with 20mm copper base.
Tested its threshold voltage and then dimmed it considerably by using it a moment without a shunt resistor, current was >10x and it wasn't intentional.
Actually dimming is a guess, based on a missing visible brightness, but anyway, it's still just fine EPROM eraser.
This one is without a light angle info but I guess 120 degrees is better than 60, no internal protection info either.

I'm still using an old fluorescent tube eraser. The timer is a noisy mechanical thing though, so I've toyed with replacing it with an electronic one.

[Vince]

Oh I didn't know about these things, they are so cute, I want one now ! 

I can offer a fully working THM560 (AC PSU module only, no battery pack; no accessories) in exchange for a fully working Tektronix DMM916, DMM870 or TX3 hand multimeter (must have holster, DMM916 preferred). I would even cover both sides of shipping. If the DMM is really fine, I would might in some accessories.

Unfortunately I don't have any Tek handheld DMM, but I would love to as well ! 

I will trade both the THM and the handhelds for a half dozen hollow-state Tek scopes. I have 7 type 317, you can have the one I have restored + a few spare scopes
Shipping will be difficult though, so plan a business trip with your company and ask them to give you the pick-up truck at the back of the workshop, rather than the Toyota Yaris at the front ! 

I don't know... I guess I should stop collecting DMMs... 

The problem I am running into is that you have to store them with no battery in them, because most of them run on a 9V battery and they are horribly expensive and it's flat by the time you get to use this or that meter (my MX53/54/56 eat the battery in just a year or two, it's horrible). So, this means I have to take the meter apart, twice, every time I want to use a meter from my collection for a few minutes... which is a pain.

So in practice I had to compromise and put a battery only in a very small percentage of my collection, and keep these meters at hand. So I have my Fluke 11 which is may daily driver, then my Wavetek 27XT then a couple Metrix MX54/56 and that's it. The others are stored / buried in plastic boxes and I seldom visit them 

[m k]

For mysterious model number my guess is a design time of a spring of '92.

I'm still using an old fluorescent tube eraser. The timer is a noisy mechanical thing though, so I've toyed with replacing it with an electronic one.

Some sort of a timer is a pretty must of must.

My last old style tube model was just a tube.
It was around a meter long and on the floor of empty and unused room.
Good part was that there were always space for all chips.
Possible down side was that forgetting them made then really blank.
I remember forgetting few chips there for so long that elapsed time became unknown.
Can't remember how those chips were afterwards.

[TERRA Operative]

Oh I didn't know about these things, they are so cute, I want one now ! 

I can offer a fully working THM560 (AC PSU module only, no battery pack; no accessories) in exchange for a fully working Tektronix DMM916, DMM870 or TX3 hand multimeter (must have holster, DMM916 preferred). I would even cover both sides of shipping. If the DMM is really fine, I would might in some accessories.

I got a working Tek 224 in a (worn) pouch with both probes and a lithium battery conversion...
Or soon a THS720 with a bunch of accessories in a bag (with new foam insert) and LED backlight conversion on a new LCD (waiting on PCB's), and standard C cell mod...
Or a selection of TDS500/600/700 series scopes
Or a selection of 2000 series analogue scopes
Or a couple TDS220 scopes, freshly calibrated, updated firmware and new LCD's
Or......... 

[Vince]

I got a working Tek 224 in a (worn) pouch with both probes and a lithium battery conversion...

( [...] lots of bragging edited out)

No Sir, you got nothing... that 224 belongs to your BROTHER ! You were merely tasked with fixing it then give it back to him.
Granted you did a nice job of it, but it still belongs to your brother. Unless your brother shows up to tell us he gave it to you, and somehow we can have proof that he didn't say so under pressure, you threatening him with a gun or some other means... then it's not your 224. 

[TERRA Operative]

Well, actshually...

He gave it to me!

But now I have the THS720P, so the 224 isn't needed besides collectors value... You want to buy it?

[Vince]

YES I do !


Please do keep it in a safe place along with my / a fully optioned up TDS 784D .
It won't change much to the size and weight of the parcel so might as well throw it in ! 
In the same vein you can keep me a sorted TDS 220 or 224 if you find one one day, with the coms interface module that you upgraded with some good stuff I remember.
That too isn't very big nor heavy so why not...

EDIT : depending on shipping cost, might be a better idea to do several shipments to mitigate the consequences of an eventual loss or damage...

[TERRA Operative]

Ha, I got a late model TDS220 with the Math Module (It is basically a comms module with the extra Math functions) which I currently use, but when I upgrade to something newer in the similar form factor (Not tooo long away..) I'll tag it with your name.
It has new caps in the PSU and a new CCFL tube in the LCD even.

I have 3 other TDS220's, but they are the older revision so I'll keep the good one for you.

The 'Vince's stuff' pile here is growing... I can only say that it's a good thing, better the gear goes where it is appreciated than some random on Yahoo Auctions....

[Vince]

Thanks a lot Terra ! 

As for the TDS220... I didn't even know there were several "versions" of it... what differs between them and how to identify them ? Can it be seen from the outside, or is it a difference in the PCB / Hardware ?

All that motivates me to fix my TDS 544A so I can make space and get some money to help finance all that Japanese stuff 

[TERRA Operative]

The only real difference is the move from EPROM for the firmware to a Flash chip, and a later firmware revision to suit.
Also, the BNC jacks have 4 mounting pegs into the PCB rather than the two pegs on the earlier models, for extra strength (I always resolder them as they can tend to get loose from years of use causing the solder to crack).

There may be more differences in the PCB (usual revision updates), but mostly to the user it is functionally identical.

Later model just means less bugs and a younger scope. They are a great scope for basic measurements, I use mine all the time as my go-to scope. Simple to use, compact and always 'just works'. Also, the 300V CatII rated inputs are nice too, harder to blow up.