Test Equipment Anonymous (TEA) group therapy thread

[Saskia]

No TE today. Yesterday got 2nd Covid shot. Everyone said the 2nd shot on the next day you will feel side effects. I'm happy to report other than sore spot at injection site no side effects.

Today was follow-up appointment with urologist. Bottom line: see you in 6 months. 

Next week is follow up with the hernia surgeon. I expect that appointment to take about 5 minutes.

Unless you lift that curve tracer ...

[Vince]

Beam found:

Build yourself a lamp limiter (aka dim bulb tester)

David

I do have one !!  I made one 3 or 4 years ago, used it once, after fixing / resurrecting the SMPS on my Tek 2232 that blew... twice... only to see it didn't work at all,  bulb was blinking at 0.5Hz, blinking, blinking.. would not stop. Remove the DBT and the scope would work just fine !

Let's see if it's more useful on an old linear power supply, should be ! 

Now the hardest part is to figure out WHERE it is ! Still  a mega cluster fuck in the house, 90% of the lab stuff is still packed semi randomly in plastic boxes following the house move...  will try to find it !

[Vince]

Those switches are also found in some car keys, including those shite thin bendy ones from the Renault Espace, here are a couple I was persuaded to try & fix, can't remember if I was successful or not.


David

Battery holder looks rather crusty / corroded (it's Britain after all !  ), might explain the failure of the switches  !.....

[Brumby]

this is just for tracking my rockets .... I don't know what you are afraid of.

Anybody got a GPS that is good for > mach 5 ?

This, linked with your fondness of 50g serves of your favourite "condiment" made me ponder on the possibilities....

[Cerebus]

this is just for tracking my rockets .... I don't know what you are afraid of.

Anybody got a GPS that is good for > mach 5 ?

This, linked with your fondness of 50g serves of your favourite "condiment" made me ponder on the possibilities....

I have suspicions that Saskia is exactly the reason there are import/export restrictions on GPSs that work at mach speeds, and thermal cameras with high refresh rates.

[Vince]

Some more TEA ! 


Last week I found a cute little thing here. A rather intriguing old looking portable scope. It looked very weird, but somehow I was attracted to it... in good nick and working, 30 Euros + 10 for shipping.. not much to lose, and first time I see one for sale... so I didn't want to let it pass.

Then I searched a bit about it... it's a very early handheld scope, late '80s, made by " Createc " , a German company.

For its age, given the specs and features that it sports, I think it must have been pretty state of the art back then.

At the least Tektronix though it was, as they rebranded it to sell it !

Tekwiki page:

https://w140.com/tekwiki/wiki/T202


There are several models I gather, depending on bandwidth. 5 or 10 or 20MHz I think.

Mine is model " SC 04 ", it's the 10MHz version.

2 channels, 20MS/s, H/W frequency counter and H/W DMM ! :-O

Also a serial port where you can attach a little printer for hardcopies ! 

don't have it sadly... but there is a thread for this scope on EEVBlog with tear down pics, where the guy show the printer in action:

https://www.eevblog.com/forum/testgear/vintage-handheld-scope-createc-sc04/

Maybe the serial port can be used for other purposes, will have to see if I can find the user (even service ?) manual for it.


It's not very usable because the user interface is completely fucked up. It's alien. I don't think it's been designed by human beings... or at least not intended to be used by them. It's NOT intuitive AT ALL. Thank God my scope came with a cute little "quick reference " chart (albeit for model SC 02 not 04 but still useful) that describes the most commonly used key combinations to set things like time base or trigger.
The only intuitive thing that you don't need a PhD in astrophysics to use, are the input couplings and attenuators settings, because they have mega huge dedicated mechanical slide switches along the edges of the case. Channel one on left side, Ch2 on the right side.  Don't think you can at least figure out where the Power On button is .. because there isn't even one ! 
Told you, not intuitive...

After a bit, I managed to display a 10kHz sine wave.. I was over the moon, felt like I had just passed a difficult exam at school or something ! 

It doesn't seem to want to display a graticule on the screen so not sure how one is supposed to measure anything with this thing ! I guess there must be a way to display it... but it ought to be on by default eh ?! 

Another reason it's not really a usable / practical scope is... well it looks like a portable scope but it's not ! It's handheld shall we say but... it is not battery powered, comes with a big power brick ! One with a weird looking proprietary connector and 7 pins which are all used : So I am glad I have the brick or else... the SCOPE would itself would become a brick as well ! 

Quick teardown piccies of the power brick because that other thread doesn't show any.
It's a mix of linear and switch mode. First there is a potted transformer (in blue, left inside the case), probably to lower the voltage a bit and allow for 110/220 V selection. Then there is a switch mode supply around good old TI 494 PWM controller chip, same as many Tek 2000 series scopes.

The DMM feature is nice. It runs full screen and displays a handful of parameters like Vpp, Vrms, Period and Frequency, taken from the H/W counter. However refresh rate is like 2 seconds or so, so it drove me a bit crazy I must admit...
But it does look cool and even show you a miniature view of the real time scope view of the signal, in the bottom right corner of the screen, so you can keep an eye on your signal while looking at the DMM ! 


So.... overall, it's such a pain to use and not even battery powered, that I highly doubt I would use it very often. Still want a more modern portable scope...

However I am very happy to have it, as it completes my collection of Tek scopes, and is my first "portable" one. Also nice to have as it's so ancient, it's great to see just how much features and performance people managed to cram into such a small form factor so early on, in through-hole technology !!    90% of it is TH ! I see 3 boards stacked on top of one another. The two biggest ones are TH. Only the outer one, facing the back of the unit, has a few SMD parts on it...


Actually my unit works really just fine, I have nothing to tweak or fix and improve, electrically... almost boring ! 
OTHO, for the better, because given the construction of the scope, serviceability / repairability is next to NIL ! 

so I think the goal with this scope is just have some fun with it. To begin with I could try to mkae it look nicer. It's case has SEVERELY yellowed as you can see, looks horrible. Could try some hardcore "retro-brighting" on it to rejuvenate it.

Could try to investigate the printer side : can I find a printer for it ? Is the printer protocol proprietary, or can it wok with some generic serial printer ? Can the UART be used to do some stuff other than printing ?
Could I design / make a battery pack for it, to make it more usable ? The sticker at the back says it draws only 3,7W. So should be able to power it for an hour with battery that's not too big.  OF course there are 7 different wires coming from the power brick, so I would need to design my own power supply to generate all these rails... hopefully in a much more compact design, thanks to SMD magic and modern componentry...
So that could be a nice little project : studying the existing power brick, reverse-engineering it, then designing a modern replacement, SMD and much more compact.

I don't know... just basically play around this old scope !

Now for some piccies...

[Zucca]

There are half a dozen cute little relays in the thing. Keyboard : tactile switches, however not the cheap kind : Look at them, 100% metallic construction ?!     Never seen luxurious ones like that... probably because all the ones I salvaged came form cheap consumer devices, not pro stuff made for field use !

Thank you for burning 10 dollars from my bank account.

[Zucca]

Sorry Microsoft, I apologize... all those blue screen... now I know...



  

 

[xrunner]

Congratulations Vince - you have presented something I have never seen before. It is kinda cute though.   

[Zucca]

BTW    Vince!!!!
Were have you been in the past two years? you are definitely a TEA family member!!!!! So cool to have you here.

[Neomys Sapiens]

At the least Tektronix though it was, as they rebranded it to sell it !

Tekwiki page:

https://w140.com/tekwiki/wiki/T202

It's not very usable because the user interface is completely fucked up. It's alien. I don't think it's been designed by human beings... or at least not intended to be used by them.

Correct.
I have a Tek-branded T202 lying around which I intend to foist onto someone as a particularly cruel joke. The recipient will never be able to operate a regular scope.
Although one must admit that Tek forced some changes in the SW and the overlay which makes it at least recognizable to a scope user, while yours is really pure evil.

Check the stars before playing with it, lest it grow tentacles and devour your brain!

I still remember that the 'Elektronik', Germany's leading professional mag at that time, gave this abomination the title page and at least 10 pages of praise and admiration.

[Neomys Sapiens]

And no, I don't have the Tek-exclusive battery unit for it. Before I had other options for a small portable scope I pondered thoughts along the same lines than you.

Here you can still see it as a part of a mobile T&M kit:

[mnementh]

Some more TEA ! 

Last week I found a cute little thing here. A rather intriguing old looking portable scope. It looked very weird, but somehow I was attracted to it... in good nick and working, 30 Euros + 10 for shipping.. not much to lose, and first time I see one for sale... so I didn't want to let it pass.

It's like they tried to do classic iMac styling.... and failed horribly. 

mnem
Like how a Vogon Deconstructor hangs in the air exactly the way a brick doesn't...

[Vince]

BTW    Vince!!!!
Were have you been in the past two years? you are definitely a TEA family member!!!!! So cool to have you here.

Where have I been ?! Well...

For the entirety of 2019 I had found shelter in a crappy room (and all my belongings put in storage unit rented at crazy high costs...) I was renting because the house builder that had just finished building my house ('in late 2018) , would not give me the keys of the house, because I was complaining about all the crap he did throughout the house... very low standards indeed...
So during 2019 I and my lawyer were fighting with the builder, so had to stay in that crappy room which... had no land line, and zero mobile network service. So for all of 2019, had no phone service and no internet ! So was kinda off the grid so to speak...
But January last year my lawyer finally managed to get me the house keys so I could move in at last ! spent 6 month sanding and painting all teh dry walls... then late last year I finally was to the point where I could install a workbench and shelves and some gear, to get the lab going, albeit in degraded mode.. but at least it was there ! So I could start having a bit of fun at long last. Then 6 months ago Tautech told me about TEA and dragged me there, thinking I might like it... I think he was right, I quite like it here, thanks Tautech ! 

[vk6zgo]

At the least Tektronix though it was, as they rebranded it to sell it !

Tekwiki page:

https://w140.com/tekwiki/wiki/T202

It's not very usable because the user interface is completely fucked up. It's alien. I don't think it's been designed by human beings... or at least not intended to be used by them.

Correct.
I have a Tek-branded T202 lying around which I intend to foist onto someone as a particularly cruel joke. The recipient will never be able to operate a regular scope.
Although one must admit that Tek forced some changes in the SW and the overlay which makes it at least recognizable to a scope user, while yours is really pure evil.

Check the stars before playing with it, lest it grow tentacles and devour your brain!

I still remember that the 'Elektronik', Germany's leading professional mag at that time, gave this abomination the title page and at least 10 pages of praise and admiration.

Mags do that, depending on the bias of the particular writer/editorial team.

One of the car magazines in Oz, years ago, had two articles in the one issue, in which one praised Peugot for the clever way in which they used an existing four cylinder engine block & "grafted an extra cylinder on" to make a five cylinder engine.
"Inspired", "Innovative", were just some of the plaudits they showered on that carmaker.

In the same issue, they slammed Holden for the "stodgy" & "pedestrian" way in which they made a "four" by "cutting off" two cylinders of a "six".

I never drove the Peugot, but despite the bashing, the " Starfire four" in a Commodore I drove a little later was very smooth, & quite capable, really not feeling much different from the "six".

Of course, both carmakers were really just optimising their parts inventory!

Way, way back, "Electronics Australia" got all worked up about the potential of "Electroluminescent street signs".
Nothing happened with them, as reflective signs were very much cheaper & didn't require a power supply!

[Vince]

Correct.
I have a Tek-branded T202 lying around which I intend to foist onto someone as a particularly cruel joke. The recipient will never be able to operate a regular scope.
Although one must admit that Tek forced some changes in the SW and the overlay which makes it at least recognizable to a scope user, while yours is really pure evil.

Check the stars before playing with it, lest it grow tentacles and devour your brain!

I still remember that the 'Elektronik', Germany's leading professional mag at that time, gave this abomination the title page and at least 10 pages of praise and admiration.

Oh OK ! Thanks for that... so Tek did not just rebrand them, they managed to get some modifications into it !  Indeed you are right, the keypad layout is MUCH more intuitive... and Firmware modified to make it possible.

And they also thought of making a much required battery pack for it ! I see also that they also modified the power requirements for the scope : the big round power connector has 7 pins (all wired up / used), whereas the Tek connector has only 5 pins !
Also looks better with the Tek blue on the sides...

Hmmm.... looks an much better proposition overall ! So it's worth keeping an eye open for these scopes, if I can find a Tek branded one for cheap, it would be an improvement.. could keep the Createc as a parts unit just in case.

Only drawback about the Tek version is that, at least on the pics of the T202 on Tekwiki, is that... it appears NOT to have the serial port any more ?! 
Maybe it had become an option.. or maybe they only offered it on the higher spec model (T202 is 5MHz, mine SC04 is 10MHz... maybe Tek did also sell the 10MHz and that one maybe had the serial port ? Dunno... )

[Vince]

Some more TEA ! 

Last week I found a cute little thing here. A rather intriguing old looking portable scope. It looked very weird, but somehow I was attracted to it... in good nick and working, 30 Euros + 10 for shipping.. not much to lose, and first time I see one for sale... so I didn't want to let it pass.

It's like they tried to do classic iMac styling.... and failed horribly. 

mnem
Like how a Vogon Deconstructor hangs in the air exactly the way a brick doesn't...

I don't think there were any " iMac "in the '80s ! 

But I get your point... but I am not sure I would agree. It's just beige like all the macs and any computer stuff of the '80s and '90's ! That's what I like actually.
Love the old beige stuff from Apple in the last century. The black case & blue LED madness that's the plague of today's consumer stuff started only 20 years ago. So basically the first 20 years of desktop computing were beige, the following 20 years were black and blue... let's see what the next 20 years will bring ! 

[tautech]

BTW    Vince!!!!
Were have you been in the past two years? you are definitely a TEA family member!!!!! So cool to have you here.

Where have I been ?! Well...

For the entirety of 2019 I had found shelter in a crappy room (and all my belongings put in storage unit rented at crazy high costs...) I was renting because the house builder that had just finished building my house ('in late 2018) , would not give me the keys of the house, because I was complaining about all the crap he did throughout the house... very low standards indeed...
So during 2019 I and my lawyer were fighting with the builder, so had to stay in that crappy room which... had no land line, and zero mobile network service. So for all of 2019, had no phone service and no internet ! So was kinda off the grid so to speak...
But January last year my lawyer finally managed to get me the house keys so I could move in at last ! spent 6 month sanding and painting all teh dry walls... then late last year I finally was to the point where I could install a workbench and shelves and some gear, to get the lab going, albeit in degraded mode.. but at least it was there ! So I could start having a bit of fun at long last. Then 6 months ago Tautech told me about TEA and dragged me there, thinking I might like it... I think he was right, I quite like it here, thanks Tautech ! 

Lol, it all started when you posted a pic of your immense stack of legacy Tek gear in another thread so it was very plain you would fit in well here so hardly a nudge was needed for you to see the obvious. 

[Neomys Sapiens]

Also looks better with the Tek blue on the sides...

Almost everything looks better with some Tek blue on the sides...am I right, med?

Maybe it had become an option.. or maybe they only offered it on the higher spec model (T202 is 5MHz, mine SC04 is 10MHz... maybe Tek did also sell the 10MHz and that one maybe had the serial port ? Dunno... )

Not as far as I know. I think it was a stopgap measure. Tek followed that up with the cute and useful 222.

[mnementh]

Some more TEA ! 

Last week I found a cute little thing here. A rather intriguing old looking portable scope. It looked very weird, but somehow I was attracted to it... in good nick and working, 30 Euros + 10 for shipping.. not much to lose, and first time I see one for sale... so I didn't want to let it pass.

It's like they tried to do classic iMac styling.... and failed horribly. 

mnem
Like how a Vogon Deconstructor hangs in the air exactly the way a brick doesn't...

I don't think there were any " iMac "in the '80s ! 

But I get your point... but I am not sure I would agree. It's just beige like all the macs and any computer stuff of the '80s and '90's ! That's what I like actually.
Love the old beige stuff from Apple in the last century. The black case & blue LED madness that's the plague of today's consumer stuff started only 20 years ago. So basically the first 20 years of desktop computing were beige, the following 20 years were black and blue... let's see what the next 20 years will bring ! 

No, I was thinking of the Berry-colored lucite iMacs of the 90s; I guess I missed where you said it was made in the 80s. Tho really... doesn't matter. It was like they were going for something cool like that, but failed.

mnem
“There is an art to flying, or rather a knack. The knack lies in learning how to throw yourself at the ground and miss... Clearly, it is this second part, the missing, that presents the difficulties.” ~HHGttG

[mnementh]

There are half a dozen cute little relays in the thing. Keyboard : tactile switches, however not the cheap kind : Look at them, 100% metallic construction ?!     Never seen luxurious ones like that... probably because all the ones I salvaged came form cheap consumer devices, not pro stuff made for field use !

Thank you for burning 10 dollars from my bank account.

  did I do now?!?

mnem
*looks all over his keyboard for the "burn $10 from your bank account" macro...*

[cyclin_al]

There are half a dozen cute little relays in the thing. Keyboard : tactile switches, however not the cheap kind : Look at them, 100% metallic construction ?!     Never seen luxurious ones like that... probably because all the ones I salvaged came form cheap consumer devices, not pro stuff made for field use !

Thank you for burning 10 dollars from my bank account.

  did I do now?!?

mnem
*looks all over his keyboard for the "burn $10 from your bank account" macro...*

It's those darn tactile switches you found on Amazon!  His currency is not the Canadian peso, so it is only $10 instead of $12.99 CAD.

-- you can tell a Canadian price by the .99 cause it appears a whole dollar cheaper that way 

EDIT:  still holding on to my wallet ... Must resist ...

[mansaxel]

Actually the cable would be less expensive than the multimode cable, if only 30m were needed. Am I on the right track ? Could I use the FTTA-cable to hook up to switches in case I need 50 m ?

It's an excellent choice for your application. The SFP is the right one, and both the "milspec" and the FTTA cables would be great.

[AVGresponding]

The SIFF CDU has bugger all inside it. I wouldn’t bother.

It sold pretty quickly (no, it wasn't me)

[duckduck]

Another 5 1/2 digit bench multimeter from the 90's. It's an HP 3468A off of the Bay of Pay. It was packed very well, but it was dirty and had a good amount of old permanent marker on it. The lithium primary battery (3V nominal) measures 3.42V, and nobody has played doctor with it. ICs have date codes of 1991.

Perhaps the 3468A isn't that interesting on it's own, but it is interesting to compare it to the Keithley 197A. The 3468A has a more modern interface with soft-touch buttons and a larger LCD. It has no backlight, but neither does the 197A, effectively. The 3468A does have HP-IL (of questionable use nowadays), and it can only measure to 300V and 3A. The Keithley can make relative measurements, measure dBm, has a built-in data-logger, and can measure the forward voltage drop of diodes. It also has safety banana jacks, and can measure 1000V and 10A. The HP has a funny shape that allows the folding bale to tuck underneath, whereas the Keithley's bale is always in the way if you aren't using it.

The 300V limit on the HP is really a deal-breaker for me (think vacuum tubes). It's either going in the sale thread or back on the 'bay from whence it came.

Getting old permanent marker off of textured plastic is a real pain. I tried multi-surface cleaner, WD-40, acetone, chlorinated brake cleaner, and car polish. The thing that seemed to offer the best results was the "magic eraser", which is a soft white sponge with a mild abrasive in it. N.B.: it creates a matte finish on the plastic and "magically erases" all printed text and graphics. It doesn't clean down into the texture, but it looks better than before.

Cerebus, HP are a step ahead of you (and hopefully me) with their warning label.

EDIT:

Anybody know the MSRP on the 197A and 3468A?