Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

I’ll take a green one that isn’t shit. You know what I miss? Intel OEM boards.

A little old-school iron DX58 (XEON with Triple-Channel RAM) pr0n just for you, buddy. 

mnem

[bd139]

Now we’re talking   

Going back further I still remember my Intel Tualatin 1.4GHz desktop. That was a custom build with intel board, Matrox G400.

[Specmaster]

Surely it is more cost-effective to have a 4K TV. I think 4K on anything less than 40" screen is not really going to be noticeably different.

Absolutely not. TVs make a horrible monitor, especially from a few feet away.

TVs are optimized for moving pictures with low dropped frames. PC monitors are optimized for crisp rendering of text and clear images. There's a reason high-FPS gaming monitors are so expensive; a panel and display driver that can do both doesn't come cheap.

mnem
 

Oops, sorry but I thought that bd was trying to get 4k TV on his computer, no arguments here, I totally agree TV's make crappy monitors.

[Saskia]

@bd I still have a working 386 here. Should I send it to you ?

[mnementh]

Interesting little video I found here.

Heh... I did a very similar "ghetto fab" project using a crashed JetSki and a small aluminum flat-bottom fishing boat when I was a teen. Having done similar "resurrection rebuilds" on more motorcycle engines than I can count, I can tell you that you pay for your "free" bits and pieces with weeks of meticulous labor.

mnem
 

[mnementh]

Now we’re talking   

Going back further I still remember my Intel Tualatin 1.4GHz desktop. That was a custom build with intel board, Matrox G400.

Yup. And you'll notice my addiction to black shellac goes back a long way... 

Intel's attention to detail was legendary; this really was industrial design brought to the masses. This "gaming" board supported ECC RAM, 3 different families of XEON processor (everything  LGA1366, tho you only got 3CH memory support on that family for obvious reasons), and lookit those VRMs.  They didn't cheap out on anything; even the chipset cooler fan was custom-made from SUNON: low-RPM, high-volume with nice not-too-bright blue LEDs.

I mean yeah, I get why they had to get out of competition with the likes of ASS-Rock and Micro-Suck International; they were taking all the R&D and FW development Intel had to do with Microsoft, XEROXing it over onto the cheapest PCBs they could produce, then beating Intel over the head with boards selling retail for 1/4 what Intel could wholesale for.

mnem
The race to the bottom comes at a cost...

[Specmaster]

Interesting little video I found here.

Heh... I did a very similar "ghetto fab" project using a crashed JetSki and a small aluminum flat-bottom fishing boat when I was a teen. Having done similar "resurrection rebuilds" on more motorcycle engines than I can count, I can tell you that you pay for your "free" bits and pieces with weeks of meticulous labor.

mnem
 

Of course, you do, but what a sense of achievement you have once it's done, For some people time might be all they can afford to throw at anything. 

[factory]

What's with the random splodges of glue down the sides of several of the bigger capacitors? Someone get board bored on the assembly line? 

Did it come with a manual? I apparently have a spare original if needed. 

David

I think it was a trend after 2010. My conspiracy theory is they are using it bring good luck after the capacitor plague
...

Mine had been made around 2000(too lazy to look it up exactly), and has the RTV/silicone fix(see here). The reason AFAIK is anti-vibration, as I've seen some other stuff(PC PSU, early(<2004) plasmatv's etc.).

I think my comment has been misinterpreted (not helped by my bad spelling), I'm aware of the use of glue between capacitors & the PCB (or between several capacitors close together), for preventing metal fatigue of the leads due to vibration.
But I've never seen it used all the way from top to bottom on capacitors that are on their own, as shown in BD's hp/Agilent PSU, see the pictures from the post I was replying to.



I've just noticed the glue on top of a couple of transistors too.

David

[Cerebus]

By the way, congrats for your PhD Wolfgang. Quite an accomplishment. 

Congratulations from my side, too! What a nice work.   
I've downloaded and started reading it. Very interesting topic!   

Thank you!

Mounty

So do we have to call you Dr. Wolfgang from now on? 

Lets stay at first names, please. Thanks anyway !

Let's compromise and call you "Nurse Wolfie". 



Congratulations on finishing your PhD, about half the people I know who have completed the actual research fall at the "writing it up stage".

[factory]

If one reads the superlatives in the datasheet, you've probably bought the best LEDs available ever

Do many do you want ?

None, you've seen the piles of stuff that I already have 

OK, let's do it vice-versa, where can I get one of these LED PCB that looks like primitive display ?

You might have been thinking of the A4gallium PCB that bigclivedotcom on youtube created, needs flashing LED's though.

http://www.bigclive.com/freebies.htm

David

[Wolfgang]

By the way, congrats for your PhD Wolfgang. Quite an accomplishment. 

Congratulations from my side, too! What a nice work.   
I've downloaded and started reading it. Very interesting topic!   

Thank you!

Mounty

So do we have to call you Dr. Wolfgang from now on? 

Lets stay at first names, please. Thanks anyway !

Let's compromise and call you "Nurse Wolfie". 



Congratulations on finishing your PhD, about half the people I know who have completed the actual research fall at the "writing it up stage".

Its absolutely correct that the "writing up" phase is the real pest. On top of that you are supposed to publish in a reviewed journal (IETE in my case). I had material for more than about 600 pages, and the recommended limit of the university was about 150 pages. On the other hand, I disproved some common concepts about oscillator operation, so I needed to be waterproof about that. Melting down all of this into roundabout 350 pages was a challenge, and I really hated it. Anyway - I got a magna cum laude and I am supposed to be satisfied with it. I can still publish some extra chapters on my webpages ... 

[tautech]

Its absolutely correct that the "writing up" phase is the real pest. On top of that you are supposed to publish in a reviewed journal (IETE in my case). I had material for more than about 600 pages, and the recommended limit of the university was about 150 pages. On the other hand, I disproved some common concepts about oscillator operation, so I needed to be waterproof about that. Melting down all of this into roundabout 350 pages was a challenge, and I really hated it. Anyway - I got a magna cum laude and I am supposed to be satisfied with it. I can still publish some extra chapters on my webpages ... 

Determined to read it all as much respect is due for anyone that has put themselves through this. 

[Vince]

11401 Tek Scope : spent a few more hours with the thing, trying to investigate my minor problems, just for fun...


1)

Slightly dim CRT : " fixed "... found a menu where you can adjust brightness. It was set to only 60%. If you set it to 100% boy it's briiiiiight.... Set it to 70% to get it just bit brighter but not too much... zero burn marks / ghosting on this 32 year old CRT so I would rather it stays that way...



2)

Inoperative " Power On " status light on the front panel. First made the assumption it was an LED, so checked with DMM in diode mode. Said open both ways. Checked in resistance mode, 27Meg both ways... chances of a status LED going open is next to nil I guess, so might be a tiny incandescent bulb ? I guess that would make more sense since the two wires going to it are both black, no "polarity", and on the PCB where it plugs to, the pins also don't give any indication of polarity whatsoever. Checked those pins with the DMM... shows 5Vdc. So I guess that's an incandescent bulb, unobtainium I imagine, but it's round and calipers say about 5mm in diameter so.... could possibly replace it with a standard green 5mm LED ?!........ worth a try I guess.



3)

 Defective probe calibrator, shows 300mVdc and no AC. This is fed by a semi-rigid coax cable, very long, that sneaks its way under the video board towards the back of the scope, then plunges between the plugins backplane and PSU, to emerge on the other side of the scope, to connect to one of the two large boards under there. See pics.
No schematics in the service manual sadly... so tried to follow traces on the PCB, backwards. It goes first to a diode, which tests good. No signal on the other side of the diode / anode. Then the anode goes to two components. A flat blue thingie that's probably some kind of capacitor ?! Then it also goes to a 3K resistor, which tests good too. Still no signal on the resistor. And that's about it because then it goes to an inner/hidden layer in the PCB, so I am screwed !     
All that the manual can tell me is that I am supposed to get 6Vpp.



4)

Scope is still hard of hearing : rarely powers up first time. Either it does not react at all, or it freezes at random places in the boot process. However it always eventually completes boot, and once it does, it works just fine for hours on end, no worries. Still zero POST errors, and zero fault as well when I manually run the extended tests suite from the Utility menu.

So I am reasonably hopeful that it's just a PSU problem, that has therefore a decent chance of being diagnosed and fixed... rather than a problem anywhere else, where the chances of diagnosing it, never mind fixing it... are slim to say the least....

Skimmed the service manual, looks like there are only two power rails, +5V for the TTL stuff, and -5.2V ... for some fast ECL logic somewhere, I guess. Can't believe that there are only two rails in this scope but... looking at the 3 largest boards in this scope, ie the 3 I can actually see, covering the top and bottom of the scope... they have a very distinct power connector, can't miss it, and they have only 2 or 3 wires, carrying indeed only +5V and -5.2V ! Wow.... how simple.
I checked both rails, they are perfect. Spot on, and next to zero ripple. As sweet as one could possibly want them to be.
So I doubt the big filter caps are gone in this PSU.... they clearly do their job.
So must be something to do with the power on timing/sequence maybe ? Maybe they are too slow to establish, and that disturbs the digital board ? I don't know... something wrong with the PSU other that merely voltage levels and ripple.

Anyway, no time  to work on this scope for now, but when I do clearly I will have to attack the PSU. It's made of 3 things : a main shielded block, and 2 more boards. Tek calls them the "regulator" board and the "rectifier" board... they are stacked on one another, and both of them are under the main block. This ensemble is not accessible at all... requires dismantling the scope. So would need to take the scope apart, and check with a scope how the rails are doing at power up, if they are lazy or glitchy or what...
I can have a very limited peek at the inside of the PSU block, through vents. I can see some big electrolytic caps and they all look brand spanking new. No obvious sign of bulging at the least. Quite a few electrolytic caps on the boards (other than the PSU I mean), but it's all through-hole and they all look like new. It's too old to have any of the dreaded first gen SMD electrolytic.... unlike my TDS 544A, ahem...
So that's good !

What else...  scope has a "health" counter : keeps track of operating time and number of power cycles.  See pic.

12,460 Hours total, and 1363 power-ups. so 9+ hours per cycle in average. So basically scope was running all day for a few years...then got retired... Cal stickers on the thing indicate it was last calibrated in 2006 IIRC.

Hardcopy / Printer : .... scope showing its age ! Only printer options I am given are : either 8 or 24 pin dot matrix output, that's it !  Doesn't even specify printer brand or model, just says " 8 pin " or " 24 pin ".. so I guess that means back in the day all dot matrix printers used the same protocol / language ?!
Maybe some Firmware update might give me more printer drivers...

[med6753]

Changing of the guard. A Type 561B now occupies bench 1 test rack previously occupied by a 475A and 2465. Every few weeks or so I rotate the scopes in that area to give them some power up time. The best thing for old equipment is the run them and it also gives me an early warning if something is amiss. If I'm working at the bench I'll power it up and just let it run. And by default whatever scope is in that location is the scope for troubleshooting any other equipment that finds itself on bench 1 for repair. After a week or two I'll rotate in something else...like possibly the two 465B's. 

[mnementh]

   

So... in tonight's Discord, I posted aboot playing around with my new Elektor project FET probe from 60dbm and my NanoVNA, and ch_scr was helping me understand what all this little box was telling me. I got as far as the above, which told me what I needed to know; that this probe presents aboot a 1.1pF load at 85Ω or greater from 10-500Mhz; indicating it was fine to probe the CPU's oscillator on my dead-ish Pioneer VSK-1022K with:



whereupon he's all like:

ch_scr  — Today at 6:05 PM
fuck
you know I have to make me one as well?
thanks I guess    

And he means from scratch out of his parts bins, just because... 

But he posted a vid showing how to do what I wanted with the nanoVNA; and damn if he didn't get me back: Next in my yoobToob queue was this little gem, which sucked up another half-hour of my life...

   

https://8bit-museum.de/sonstiges/hardware-projekte/hardware-projekte-chip-tester-english/

... and now I want to build one of these myself. A tester for most of the old-school memory and logic chips we've all been hoarding forever, so you can actually know if they're any damned good. And, on top of that, it'll do a dump to microSD for you!

Manual is here: https://8bit-museum.de/download/chiptester-pro/README_Pro_1.2.pdf

   

Noel sez the total BOM is 87€ (plus a USB-ASP programmer which I'm pretty sure we all have) or right aboot US$100, depending on how you fill out the BOM from your favorite supplier or cupboard; it is not sold as a kit but rather bare boards with Atmega2650 soldered in place.

Available here in the UK as well, with lots of add-ons as well: https://www.silicon-ark.co.uk/retro-chip-tester

The way I figure it, not only is there oodles of kit-building/solder-ily afternoon fun, it is also something most of us have actually desperately needed for a long time, but couldn't be arsed to dredge up and collect all the very expensive commercial testers for those chips. Just remember to get the 4-line LCD display, not the 2-line one like Noel did; he's not very good aboot RTFM before the build. 

Noel's video also led me to this github: https://github.com/openscopeproject/InteractiveHtmlBom it is a HTML script for generating a searchable parts layout from boards laid out in KICAD, EAGLE and FRUSTION360; something which is actually making me think aboot diving into Frustion360's PCB design capabilities... 

mnem
you're all fucking welcome!

[beanflying]

Small added Rabbit Burrow  Getting square and flat.

Now I just need a better test indicator, smaller holder and or a larger surface plate and a ............ 

[bitseeker]

Thanks, yes it has .. dave showed last years picture so its even worse 

This year it looks far better IMO. 

Yes more Siglent 

And stacked better, too.

[bitseeker]

Oculus, the info you requested in the Type 454 Horizontal Amplifier.

Voltage drop across R1014. 66.8V.



Voltage drop across R1024. Identical 66.8V.  (Trace on center line, Horizontal position centered, no signal, trigger set to Auto.)



I'll leave the scope out of the case for the rest of the day in case you need more data. I will not be on Discord later today.

Stop posting Tek porn. You're going to turn my house blue 

Hmm, perhaps the official TEA color should be TEAL.

[bitseeker]

By the way, congrats for your PhD Wolfgang. Quite an accomplishment. 

Congratulations, Wolfgang! Erm... Dr. Wolfgang.

[0culus]

Oculus, the info you requested in the Type 454 Horizontal Amplifier.

Voltage drop across R1014. 66.8V.



Voltage drop across R1024. Identical 66.8V.  (Trace on center line, Horizontal position centered, no signal, trigger set to Auto.)



I'll leave the scope out of the case for the rest of the day in case you need more data. I will not be on Discord later today.

Stop posting Tek porn. You're going to turn my house blue 

Hmm, perhaps the official TEA color should be TEAL.

I'll bet Sherwin-Williams could mix bd up some Tek blue for his walls. LOL 

[VK5RC]

Its absolutely correct that the "writing up" phase is the real pest. On top of that you are supposed to publish in a reviewed journal (IETE in my case). I had material for more than about 600 pages, and the recommended limit of the university was about 150 pages. On the other hand, I disproved some common concepts about oscillator operation, so I needed to be waterproof about that. Melting down all of this into roundabout 350 pages was a challenge, and I really hated it. Anyway - I got a magna cum laude and I am supposed to be satisfied with it. I can still publish some extra chapters on my webpages ... 

Determined to read it all as much respect is due for anyone that has put themselves through this. 

Bloody well done - sounds like a great topic.
 
My middle daughter is in the 'eyeing off' stage considering a PhD having just finished Honours (botany, DNA studies) - little so and so got 1st class, (I will cut her out of the will for upstaging her father - HiHi 😁) - for her, a PhD probably is the right direction, it wasn't for this little black duck - after the 1st and only 20min meeting with one of the only options for a supervisor - I wanted to kill him - I didn't think a few years working with him would be a good idea. 😜. Was a bit sad as I had got Ethics committee approval for the preliminary and final study and had completed the trial - all looking pretty promising but I couldn't face that guy - no one else even close to suitable in the whole department, in the end it was the right choice for me👍.

[bitseeker]

...Next in my yoobToob queue was this little gem, which sucked up another half-hour of my life...

   

https://8bit-museum.de/sonstiges/hardware-projekte/hardware-projekte-chip-tester-english/

... and now I want to build one of these myself. A tester for most of the old-school memory and logic chips we've all been hoarding forever, so you can actually know if they're any damned good. And, on top of that, it'll do a dump to microSD for you!

Manual is here: https://8bit-museum.de/download/chiptester-pro/README_Pro_1.2.pdf

   

Noel sez the total BOM is 87€ (plus a USB-ASP programmer which I'm pretty sure we all have) or right aboot US$100, depending on how you fill out the BOM from your favorite supplier or cupboard; it is not sold as a kit but rather bare boards with Atmega2650 soldered in place.

Available here in the UK as well, with lots of add-ons as well: https://www.silicon-ark.co.uk/retro-chip-tester

The way I figure it, not only is there oodles of kit-building/solder-ily afternoon fun, it is also something most of us have actually desperately needed for a long time, but couldn't be arsed to dredge up and collect all the very expensive commercial testers for those chips. Just remember to get the 4-line LCD display, not the 2-line one like Noel did; he's not very good aboot RTFM before the build. 

Noel's video also led me to this github: https://github.com/openscopeproject/InteractiveHtmlBom it is a HTML script for generating a searchable parts layout from boards laid out in KICAD, EAGLE and FRUSTION360; something which is actually making me think aboot diving into Frustion360's PCB design capabilities... 

Yeah, I caught that vid, too. Seems a nifty tester. I'd want to do a V2.0 on the human interface. Ah, I can't wait to retire.

Poor Noel. Reading is rather important.

[tautech]

Its absolutely correct that the "writing up" phase is the real pest. On top of that you are supposed to publish in a reviewed journal (IETE in my case). I had material for more than about 600 pages, and the recommended limit of the university was about 150 pages. On the other hand, I disproved some common concepts about oscillator operation, so I needed to be waterproof about that. Melting down all of this into roundabout 350 pages was a challenge, and I really hated it. Anyway - I got a magna cum laude and I am supposed to be satisfied with it. I can still publish some extra chapters on my webpages ... 

Determined to read it all as much respect is due for anyone that has put themselves through this. 

Bloody well done - sounds like a great topic.
 
My middle daughter is in the 'eyeing off' stage considering a PhD having just finished Honours (botany, DNA studies) - little so and so got 1st class, (I will cut her out of the will for upstaging her father - HiHi 😁) - for her, a PhD probably is the right direction, it wasn't for this little black duck - after the 1st and only 20min meeting with one of the only options for a supervisor - I wanted to kill him - I didn't think a few years working with him would be a good idea. 😜. Was a bit sad as I had got Ethics committee approval for the preliminary and final study and had completed the trial - all looking pretty promising but I couldn't face that guy - no one else even close to suitable in the whole department, in the end it was the right choice for me👍.

Yeah that's truly sad when educators at that level aren't of the right temperament or caliber to help anyone regardless of color, creed or persuasion.   

Did 5 years on a NZ Board of Trustees which was a great eye opener to good governance and the success that comes from appointing a top principal who's guiding mantra like ours on the board was we're only here for the educational advancement of the kids. Everything we did revolved around that and the school achievement jumped several percent amongst its peers as a result.
Quite amazing what key staff can accomplish especially when they had 17 ethnicities to cater for.

[ch_scr]

Yeah, I caught that vid, too. Seems a nifty tester. I'd want to do a V2.0 on the human interface. Ah, I can't wait to retire.

Poor Noel. Reading is rather important.

Well I can't see the fluff with a tester like this, especially with the price and UI 
The TL866II Pro "eeprom" programmer that also does flash, bios, etc. also has a chip tester as well for 300 different logic IC.
And at less of a price with better UI? And you can programm/backup all the stuff you ever need with it?
http://www.xgecu.com/MiniPro/TL866II_List.txt IC support list, logic IC at the bottom
https://de.aliexpress.com/item/33044138570.html make sure to get the "866II plus"
It's less of a solder project so, I give you that 

[bitseeker]

Well I can't see the fluff with a tester like this, especially with the price and UI 
The TL866II Pro "eeprom" programmer that also does flash, bios, etc. also has a chip tester as well for 300 different logic IC.

Totally different devices to support different use cases. For example, the first thing I looked up after reading your post were the RAM chips for a Tandy/Radio Shack Color Computer 1: 2104 (4Kx1) and 4116 (16Kx1). Both are supported by the Retro Chip Tester, neither by the TL866II Pro. I'm sure there will be other examples, because the focus of the products is different.

Yes, the UI leaves a lot to be desired, as I eluded to previously. Had I the free time available, I'd probably just make my own retro chip tester. It's not like I have that many retro computers, thankfully.