Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

Beware! We had quite a few of these "always on" - after only a year a considerable number had gone bust; not only faded but missing lines and various glitches 
In general, blue OLED have the shortest lifetime of the "phosphor", yellow has AFAIK the longest.

I was counting on that year but how about a few days?

It is my suspicion that these "super-cheap" AliEx OLED displays (and probably the driver chips on the FPC as well) are probably B or C or outright reject stock that were dumped by major producers as faulty or maybe too many bad per panel. Then the bottom feeders come and do the "playing the odds game" on how many faulty displays actually go out vs how many buyers can actually be arsed to hassle them for a replacement...

mnem
 

[bd139]

@BD139

Just noticed that PCBWay are now offering transparent solder mask, and if I remember correctly you were looking for the same.

Ahha thanks for the heads up on that one. Much appreciated. I will run next order through them 

[Cerebus]

It is my suspicion that these "super-cheap" AliEx OLED displays (and probably the driver chips on the FPC as well) are probably B or C or outright reject stock that were dumped by major producers as faulty or maybe too many bad per panel. Then the bottom feeders come and do the "playing the odds game" on how many faulty displays actually go out vs how many buyers can actually be arsed to hassle them for a replacement...

mnem
 

I think that's probably unnecessarily paranoid. The truth is that OLED just isn't 'there' yet for 24x7x365 operation. I've heard a lot of reports of OLEDs used in first tier equipment, like HPAK multimeters, that have exhibited short lifetimes relative to more mature display technologies, and that's without the stress of 24x7x365 operation.

[mnementh]

I dunno... we use a lot of the cheapies with our RC tinkery. Things like FPV receivers and add-ons for our transmitters and even for debug on FCs when they're on the ground. Infant mortality rate is high enough we usually buy in lots of 3 or 5 to make sure we have at least one or 2 spares per project; and we often wind up needing them. EDITED to adjust overly broad generalizations.

I dunno... I used a lot of the cheapies with my RC tinkery. Things like FPV receivers and add-ons for my transmitters and even for debug on FCs when they're on the ground. Infant mortality rate was high enough I usually bought in lots of 3 or 5 to make sure I had at least one or 2 spares per project; and I sometimes wound up needing more than 1 spare. This was common enough that we did have discussions on it.

I gotta think that major manufacturers demand better and get better than that.

mnem

[xrunner]

I have more displays in my box-o-goodies, both OLED and LCD. The LCDs I have don't do graphics like this can though (which I will be utilizing). I didn't have another like the one that went bad, but I do have several smaller ones, 0.96", but with the same 64 x 128 pixels (SSD1306 controller). The top 16 rows of pixels are yellow and the rest blue. I have more work to show than you have seen, but all I needed to do was switch libraries, change a few lines of code, and they work the same with no changes in any scaling (but again they are too small now for my tastes).

I think I'll 3D print the enclosure for this display project so it sits under or on top of my GPSDO. I may yet still go with the OLED, I need to do some shopping. But if it fails - meh - I'll just port what I have over to some other graphics display and make another enclosure. It's not like it's mission critical stuff. 

[med6753]

Of course the weather turned hot again so this boy is much grouchier than normal because it's hot and uncomfortable in here. So just for giggles I plugged in and turned on the window A/C. It has been running now for several hours with NO funny business. The control board is behaving and responding to commands. So apparently there is a very intermittent issue. When I pull it out in a few weeks I'm going to put it in the garage rather than in here in the closet so I have room to rip it down and see if I can get to the control board. Maybe I'll get lucky and it is nothing more than a leaky cap or perhaps a spider or two got in there.

After being on for about 4 hours the random function change and beeping has returned. But interestingly it does NOT change the function of the cooling unit itself. It's still running happily at the temperature initially set and providing cooling. So for now I'm just ignoring the random beeping because it's still hot/humid but comfortable in here. 

[mnementh]

I have more displays in my box-o-goodies, both OLED and LCD. The LCDs I have don't do graphics like this can though (which I will be utilizing). I didn't have another like the one that went bad, but I do have several smaller ones, 0.96", but with the same 64 x 128 pixels (SSD1306 controller). The top 16 rows of pixels are yellow and the rest blue. I have more work to show than you have seen, but all I needed to do was switch libraries, change a few lines of code, and they work the same with no changes in any scaling (but again they are too small now for my tastes).

I think I'll 3D print the enclosure for this display project so it sits under or on top of my GPSDO. I may yet still go with the OLED, I need to do some shopping. But if it fails - meh - I'll just port what I have over to some other graphics display and make another enclosure. It's not like it's mission critical stuff. 

Yup. Have oodles of them in my junk in storage; just bought a 3-pack of that very display for my Circuit Python box a couple months ago. Plug-in SPI bus and cheap as chips makes it still cost effective even if you do have failures.

mnem
moo...?

[tautech]

Of course the weather turned hot again so this boy is much grouchier than normal because it's hot and uncomfortable in here. So just for giggles I plugged in and turned on the window A/C. It has been running now for several hours with NO funny business. The control board is behaving and responding to commands. So apparently there is a very intermittent issue. When I pull it out in a few weeks I'm going to put it in the garage rather than in here in the closet so I have room to rip it down and see if I can get to the control board. Maybe I'll get lucky and it is nothing more than a leaky cap or perhaps a spider or two got in there.

After being on for about 4 hours the random function change and beeping has returned. But interestingly it does NOT change the function of the cooling unit itself. It's still running happily at the temperature initially set and providing cooling. So for now I'm just ignoring the random beeping because it's still hot/humid but comfortable in here.

Sounds like dying PSU caps for sure.
Our nearly 20yr old dishwasher started such BS a little while ago but power cycling seems to fix it for a while.
Old laser printer loses its USB and LAN connection too which I'll bet is bad PSU caps too which solves the riddle why PSU PCB's are available for them all over eBay.

[Vince]

Today's installment on the 575. Not much happened but hey, progressing none the less 

https://www.eevblog.com/forum/repair/tektronix-type-575-curve-tracer-repair-and-restoration/msg3690901/#msg3690901

[Specmaster]

Oh I’m the sort of bastard who they should be scared of. Recently someone sent me a UPS package scam link by SMS. I contacted the one man shit box colo based in Iceland hosting it and they told me they only respond to local legal jurisdiction letters and to go away.

So they ended up getting “the wrath of having fuck loads of cheap VPS hosting credits” unleashed at them. I burned 13TB of my bandwidth quota before it melted the other end  . 20 nodes running “ab” 500 threads per node on their 1MB JavaScript hairball.

I bet that made up for not being able to execute those bastard caps yesterday, and brought a smile to your face then eh?

[Kosmic]

Talking about soldering iron, anybody know if the new T245 JBC Clone are any good ? Supposed to be 200W. I really doubt it.

https://www.aliexpress.com/item/1005002983155657.html



Edit: Was reviewed over here doesn't look bad.

[25 CPS]

This came up in my Youtube feed:



Notice at the 4:07 mark what they've repurposed to hold the equipment on?

[AaronLee]

I give up. What is a system source device used for?

It's used to measure the depth of one's pockets.

[Brumby]

I thought that's what the Infiniium scopes were for.

[AaronLee]

I thought that's what the Infiniium scopes were for.

Infiniium scopes are, but in addition they also measure the level of insanity.

[mansaxel]

This came up in my Youtube feed:



Notice at the 4:07 mark what they've repurposed to hold the equipment on?

They might, but there were a lot of special carts made for broadcast too. For later versions of Slo-Mo we employed tape (Betacam or Digital Betacam, most of the time), coupled to a controller that looks pretty much like that one, minus the clock face; time was displayed using 7-segment LEDs. Remote connection was RS-422 using 9-pin D-sub and a protocol that IIRC comes from Sony. Now, we have HDD recorders, most of the time from EVS in Belgium. The only thing telling that they're not a tape machine from the rear is the PCI slots; the rest is covered in 75Ω BNC and XLRen.  The EVS remote handles, well, they look pretty much like that one, minus the clock face; time is displayed using a LC display. Remote connection is RS-422 using 9-pin D-sub and a protocol that IIRC comes from Sony. We've successfully built a TCP/IP remote solution using Moxa terminal servers...

[ch_scr]

I give up. What is a system source device used for?

It's used to measure the depth of one's pockets.

These units certainly are quite long at 460mm / 17½"

[bd139]

Talking about soldering iron, anybody know if the new T245 JBC Clone are any good ? Supposed to be 200W. I really doubt it.

https://www.aliexpress.com/item/1005002983155657.html



Edit: Was reviewed over here doesn't look bad.

I bet that’s Chinese watts. They are like American gallons 

[bd139]

Oh I’m the sort of bastard who they should be scared of. Recently someone sent me a UPS package scam link by SMS. I contacted the one man shit box colo based in Iceland hosting it and they told me they only respond to local legal jurisdiction letters and to go away.

So they ended up getting “the wrath of having fuck loads of cheap VPS hosting credits” unleashed at them. I burned 13TB of my bandwidth quota before it melted the other end  . 20 nodes running “ab” 500 threads per node on their 1MB JavaScript hairball.

I bet that made up for not being able to execute those bastard caps yesterday, and brought a smile to your face then eh?

Annoyingly there’s no real satisfaction doing this due to the automation.

I do have a large bag of 1uF 25v capacitors here which I am considering stuffing across the mains though 

[med6753]

I bet that’s Chinese watts. They are like American gallons 

It proves we ain't stingy. Now here's a rope. 

[shakalnokturn]

Annoyingly there’s no real satisfaction doing this due to the automation.

I do have a large bag of 1uF 25v capacitors here which I am considering stuffing across the mains though 

A few guidelines for your new project:

[capt bullshot]

Oh I’m the sort of bastard who they should be scared of. Recently someone sent me a UPS package scam link by SMS. I contacted the one man shit box colo based in Iceland hosting it and they told me they only respond to local legal jurisdiction letters and to go away.

So they ended up getting “the wrath of having fuck loads of cheap VPS hosting credits” unleashed at them. I burned 13TB of my bandwidth quota before it melted the other end  . 20 nodes running “ab” 500 threads per node on their 1MB JavaScript hairball.

I bet that made up for not being able to execute those bastard caps yesterday, and brought a smile to your face then eh?

Annoyingly there’s no real satisfaction doing this due to the automation.

I do have a large bag of 1uF 25v capacitors here which I am considering stuffing across the mains though 

Sometimes here (@work) serious stuff gets tested: figure a 400V 3phase supply, capable of delivering 100A or more, a 3ph bridge rectifier and a series/parallel combination of e.g. 820uF / 400V electrolytics. For testing, one of the electrolytics gets shorted. Nice boom happens a few line frequency cycles later, sometimes blowing the enclosure of the tested apparatus apart. As it is company confidential, I can't post videos of such fun, alas.

[BU508A]

Oh I’m the sort of bastard who they should be scared of. Recently someone sent me a UPS package scam link by SMS. I contacted the one man shit box colo based in Iceland hosting it and they told me they only respond to local legal jurisdiction letters and to go away.

So they ended up getting “the wrath of having fuck loads of cheap VPS hosting credits” unleashed at them. I burned 13TB of my bandwidth quota before it melted the other end  . 20 nodes running “ab” 500 threads per node on their 1MB JavaScript hairball.

I bet that made up for not being able to execute those bastard caps yesterday, and brought a smile to your face then eh?

Annoyingly there’s no real satisfaction doing this due to the automation.

I do have a large bag of 1uF 25v capacitors here which I am considering stuffing across the mains though 

Sometimes here (@work) serious stuff gets tested: figure a 400V 3phase supply, capable of delivering 100A or more, a 3ph bridge rectifier and a series/parallel combination of e.g. 820uF / 400V electrolytics. For testing, one of the electrolytics gets shorted. Nice boom happens a few line frequency cycles later, sometimes blowing the enclosure of the tested apparatus apart. As it is company confidential, I can't post videos of such fun, alas.

Your company has consulted ElectroBOOM? 

[capt bullshot]

Oh I’m the sort of bastard who they should be scared of. Recently someone sent me a UPS package scam link by SMS. I contacted the one man shit box colo based in Iceland hosting it and they told me they only respond to local legal jurisdiction letters and to go away.

So they ended up getting “the wrath of having fuck loads of cheap VPS hosting credits” unleashed at them. I burned 13TB of my bandwidth quota before it melted the other end  . 20 nodes running “ab” 500 threads per node on their 1MB JavaScript hairball.

I bet that made up for not being able to execute those bastard caps yesterday, and brought a smile to your face then eh?

Annoyingly there’s no real satisfaction doing this due to the automation.

I do have a large bag of 1uF 25v capacitors here which I am considering stuffing across the mains though 

Sometimes here (@work) serious stuff gets tested: figure a 400V 3phase supply, capable of delivering 100A or more, a 3ph bridge rectifier and a series/parallel combination of e.g. 820uF / 400V electrolytics. For testing, one of the electrolytics gets shorted. Nice boom happens a few line frequency cycles later, sometimes blowing the enclosure of the tested apparatus apart. As it is company confidential, I can't post videos of such fun, alas.

Your company has consulted ElectroBOOM? 

People here are about sane enough to not build a jacobs ladder from MOTs and then try to catch it with bare hands
But anything else (like bureaucracy, management, ...), yes it looks like inside a madhouse, but can't tell apart who's a warden and who's an inmate. So acting like Mehdi or Andy would rather be a sign of sanity

[Robert763]

Hard to beat a lightning direct effects high energy test for deliberate electrical Ka-Boom with uncertain outcome.

The ultra high voltage attacnment and isolation tests look impressive but they don't blow the test item apart (and sometimes through the roof, literally) like the high energy tests. 

Typically 3 parts to the applied test current. It starts with 200,000A for 500us with a 50us 10% to 90% rise time (3200A/us). Then 2,000A for 5ms followed by 200 coulombs in 0.25s to 1s at 200A to 800A.
First two are capacitor discharge, last was historically a big bank of commercial vehicle batteries but some people now use big DC power supplies.