Test Equipment Anonymous (TEA) group therapy thread

[BU508A]

Yep. That's one of the reasons I sell 10 yo Agilents, Flukes, Keithleys, whatever for the price of modern Rigols or Sigilents.

Have you ever considered to add a HV source whenever you are selling a Rigol or Siglent DMM?   

[Ice-Tea]

Never sold anything Rigol or Sigilent. Had three devices in total, two are now dead.

[bd139]

I suspect the devices are made in the same way that the Belarussian software engineers I encountered used:

Start with a specification and only fulfil the extremely narrow path towards achieving that. Any deviation from the path is filled with bugs, crocodiles, stray crhulhu etc. Never protect the user. Never protect the product. Because it costs $1 more.

[med6753]

Those 3478A are all nice and dandy, but where is the backlight? 

Exactly, I know you guys have urged me in the past to get one, and I almost did, but just not liking the LCD display.

LED's are more better. 

[xrunner]

Those 3478A are all nice and dandy, but where is the backlight? 

Exactly, I know you guys have urged me in the past to get one, and I almost did, but just not liking the LCD display.

LED's are more better. 

They look OK in decent lighting, like the kind you are supposed to be working in. 

I do admit I've left hp models like these on all night though, because there is no power on LED. Turn off the light and go to bed not seeing power lights. Not sure why they made that design decision.

I have another thread on the 5385A but I ran into another design issue with cleaning the buttons. The 1.0 s gate button had to be pressed hard before it would work. But it can't be cleaned easily due to a design decision to make that assembly so it can't be taken apart. 

But I managed to get around that, at least for a couple of buttons. 

[bd139]

Oh nasty. Mines like that too. Just checked the pictures. Technically you can snip the metal rings off and install new ones but that’s not ideal. Especially if you can’t remember what they are called 

Button issues are a pain like that. My thermostat has the same problem. Needs cleaning very regularly for it to keep working.

[xrunner]

Oh nasty. Mines like that too. Just checked the pictures. Technically you can snip the metal rings off and install new ones but that’s not ideal. Especially if you can’t remember what they are called 

Yea I mucked around with trying that on this one. But it was looking like I'd end up turning into a "gorilla" like is described in these pages and I couldn't bear that hanging over me. But if the issue was bad enough, you'd have to.

Yea, what are those rings called? Push-on bastards? 

[bd139]

Push-on bastards it is  . Actually I just found they are starlock washers apparently. Think I prefer your name as it’s more accurate.

I respect your desire not to gorilla that counter 

[tggzzz]

OK, here's my contribution to HPxxxx == thread page number

[Brumby]

Ah ..... an entry from the "alternative reality" crowd.

[Brumby]

OK .... I'll join in...

[Saskia]

scraped together a few pieces and have a usable PC (still need to assemble):
case (would be one of 3 Fractal Design cases, Define R4, Define S, or one of the not so Define series, Corsair RM550X PSU, Z390 D (Gigabyte), i7-9700 8 core, 16 GB GSkill 3200, the Adata SSD (replacement for the one which went puffff), and an RTX 2070

If any of you are in need of one, this is a surplus. CPU, mainboard and SSD are new, the RTX still has 3 years of warranty.

Shipping possible

[BU508A]

Received today some nice things:

Some measurement leads from Stäubli/Multicontact


Five electrometer grade opamps from Analog Devices, AD549LH, datecode 9014


and some FR4 PCBs for tinkering

[mnementh]

Congratulation, you've done a dam(pun intended) good job; now you have a good Mac video card, which I would recommend to use it only when needed. And for future references: the reflowing can be re-done a few times, if needed

Yeah, I'm studying the airflow through this thing right now; I have a couple ideas for ensuring it gets nice cold outside air in hopes of preventing future relapse. If this thing does wind up as my *NIX workstation, it may very well be on a high duty cycle, as I am old and pretty slow anymore. 

The critical temperature is 60^oC, IIRC; that's the temperature when the underfill became jelly, and all the pressure from the heatsink will get transfered to the bumps - which, being softish material will compress a little bit. Cool down, the underfill became solid again, and will try to extend the bumps a bit. Repeat and rinse, until you have a dead videocard.
Conclusion: those videocards can have a long and happy life, if kept under to 50^oC.
The original articles which I was thinking to be on the semiaccurate, in fact were on theinquirer, and not available anymore. Original links:
http://www.theinquirer.net/inquirer/news/1004378/why-nvidia-chips-defective
http://www.theinquirer.net/inquirer/news/1013947/nvidia-should-defective-chips
http://www.theinquirer.net/inquirer/news/1036374/nv-should

They're still there, but you have to find them on the Wayback Machine. I found a page where the author had created list of links to the relevant pages there for all the BumpGate schtuffs.

The suck thing is that this machine already has some really excellent 3-chamber flow-thru airflow design; essentially a separate little wind-tunnel channel for each of the PSU, GPU, and CPU. You'd think that if any design could keep these fragile little snowflakes from melting under normal use, it'd be this one.  While it may have been a victim of Apple's aggressive noise management practices, there really is some massive heat mitigation going on here.

I'm still thinking aboot how best to improve on this excellent design...

mnem
 

[bd139]

Received today some nice things:

Some measurement leads from Stäubli/Multicontact


Five electrometer grade opamps from Analog Devices, AD549LH, datecode 9014


and some FR4 PCBs for tinkering

Got to say that those FR4 boards are pretty good value for money. I have a stash waiting for me to use up the Roth ones first.

[mnementh]

Just fried my Rigol DM3058E.

End of message. Carry on.

Found you a 34401A you can buy to replace it  eBay auction: #143981804612 same seller seems to have a rough Solartron too.

He'll just have to stock up on 34410a and 7150 - there are plenty at Ramco next week

Already bookmarked 

More interestingly, what did he do to fry it?

As it would seem, if you have a HV source and it's still set to 2kV when you turn it on, it should not be connected to a DM3058E. Who knew.

Oooooooh.... that's gotta sting. 

Also, proud of you for fessing up. I rate that one 0.6 on the BumbleButt scale . 

mnem
tzzzzzt. It's what's for dinner.

[mansaxel]

Oh nasty. Mines like that too. Just checked the pictures. Technically you can snip the metal rings off and install new ones but that’s not ideal. Especially if you can’t remember what they are called 

Button issues are a pain like that. My thermostat has the same problem. Needs cleaning very regularly for it to keep working.

Our kitchen scales is similar. Its button set is one of those rubber mats with small black dots on the back. The LCD window acts like a funnel to direct various fluids into the crack between PCB and rubber. Not very splash-proof. When the buttons get hard to press we now can strip it in 3 minutes (including fetching the closest iFixit bit driver kit), clean it, dry it, and slam it together in 7 more.

Last time it was the wife who performed it (It's her iFixit kit which is the closest one) and happened to cause the final strands in the battery -> PCB cable to break. Not her fault, bad solder joints and very bad 40AWG cable. That Far East extra-thin brand. There's some 0,22mm² super-stranded Lapp brand cable there now. Soldered using Balver Zinn. (thanks!)

[bd139]

Is that a salter one? Same trouble if it is. I had to do some board level repair on it last time to bypass the corrosion 

[mnementh]

Received today some nice things:

Some measurement leads from Stäubli/Multicontact      Five electrometer grade opamps from Analog Devices, AD549LH, datecode 9014   

and some FR4 PCBs for tinkering   

Those PCB kits are entirely too good quality for the money. Even the cheap-ass dwagon was impressed.

mnem
The cheap ass-dwagon still sez "You bare and we'll share it; Honey you know I ain't shy!!!"

[mnementh]

Push-on bastards it is  . Actually I just found they are starlock washers apparently. Think I prefer your name as it’s more accurate.

I respect your desire not to gorilla that counter 

They're called push nuts. And they are readily available in a variety of sizes & styles (including decorative caps for axles) for cheap on fleaBay and AliEx, as well as most industrial catalogs.

https://www.google.com/search?q=push+nut&tbm=isch&ved=2ahUKEwiOt5na39rvAhXuA50JHXMYDaUQ2-cCegQIABAA&oq=push+nut

Star-Lock washers are actually a variety of serrated lock washer. They look similar, but are not the same.

mnem
*currently icing my own tenderized nuts and burning a MINT install disc*

[BU508A]

Anybod interested in a 500MHz 4-channel LeCroy Waverunner scope?
NAWTS

https://www.ebay.com/itm/133710005122

[bd139]

Push-on bastards it is  . Actually I just found they are starlock washers apparently. Think I prefer your name as it’s more accurate.

I respect your desire not to gorilla that counter 

They're called push nuts. And they are readily available in a variety of sizes & styles (including decorative caps for axles) for cheap on fleaBay and AliEx, as well as most industrial catalogs.

https://www.google.com/search?q=push+nut&tbm=isch&ved=2ahUKEwiOt5na39rvAhXuA50JHXMYDaUQ2-cCegQIABAA&oq=push+nut

Star-Lock washers are actually a variety of serrated lock washer. They look similar, but are not the same.

mnem
*currently icing my own tenderized nuts and burning a MINT install disc*

Ahha thanks for the clarification! 

[AVGresponding]

Those 3478A are all nice and dandy, but where is the backlight? 

Never mind the backlight, where are the x3478x display readings? Half a job!

[AVGresponding]

Shittt I'll have to wait right round to page 4503 now then... I think I'll take a kip in the meantime.

Already made my page 4503 pic... and yes, it has the meter displaying 4.503 volts. What with that and the pics of my 3468, now you know why I was messing about with my voltage standard the other day...   

[xrunner]

Ahha thanks for the clarification! 

Nice to know, but how do you un-push them?