Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

Got a phone call in the morning, from my father, his central heating system not working. Never mind in summer, but no hot water too. In Germany the usual way is a burner heating both the central heating and the hot water tank through a shared water circulation system.

Anyway, when I arrived, I found the controller dead, no display, no power on LED. It's a quite modern one, so no way to run it in emergency mode (the older ones can work on an electromechanical thermostat and near to none electronics involved).

So we call the service, because my father would like to have hot water asap again. The guy arrived later, checked the system, phoned the manufacturers hotline (they're quite good at that, one can reach them 24/7 with the correct SLA). Diagnose: Controller defective, have to order a new one. Will arrive on monday (for more money involved, one can get spares within hours). Agreed on that, but I mentioned, I might be able to repair on component level, it's just electronics. The repair guy agreed, if I can't fix it, we should call him on monday, and he'll have the spare part on tuesday.

So I took the controller home, and found this cause for the malfunction:

   and this poor resistor.   

Lucky enough, nothing else was damaged, the thing works again and my father has hot water again since an hour ago.

It was an easy fix, but I'm a bit concerned about the quality of stuff thats supposed to last 10 to 20 years (this unit is around 4 years old). Carbonization shouldn't happen here, since creeping clearance was fine for the applied voltage.

That carbonization is from something carrying the ignitor voltage from the flyback xfmer right there to a place where it doesn't belong. Could be a wire in the harness got too close, could be condensate formed a bridge which allowed an arc to make a permanent path.

Now that the HVAC tech has disturbed the wiring, no telling for sure where this happened; you should inspect all the wires carefully for arc burns lest it happen again. Usually when you see a ballast resistor toasted like that other one, it's a indicator that the driver transistor has shorted or gone leaky, so inspect that as well before you go through the assache of installing the board. Another possibility; that resistor is a symptom of the arc having damaged something in the flame sensor. Modern controllers do this through the igniter gap by flame rectification.

Good hunting!

mnem
 

Sorry dwagon, you're completely wrong. This is the SMPS snubber (RCD type), supposed to catch the flyback as you said, but contained within a plastic box within a sheet metal box, so it's good enough protected from the installing gorillas hands and wiring harnesses and won't collect dust nor get wet while running. It's well engineered and protected, my guess it's just a dud, some mishap at the manufacturers SMT / THT assembly line. The carbonized path formed between said snubber circuit and a well defined GND potential on the PCB, nothing random, and there's been well defined creepage distance applied by the layouter.

So what, you think a random bit of crap of some sort during manufacture or assembly? That kind of arcing usually requires some encouragement, either in the form of a contaminant or excessive ignitor electrode gap causing high potentials to go strange places. Otherwise the manufacturer should have a recall on the part; regulatory agencies get pretty testy about any recurring fault on a gas controller board.

mnem
 

[capt bullshot]

Yep, I believe it's been some kind of PCB contamination that made it through the manufacturing process into the end product. Engineering wise, everything looks done right here. From my day job, I'm pretty familiar with all the compliance and conformance and certifying stuff that gets involved with such kind of electronics.

Edit: Something made me think about it again. It's a snubber node, so it's exposed to a high dU/dt voltage of up to 350V amplitude. No significant overvoltage will happen here under normal operating conditions. Creepage and clearance is fine for that voltage, but high dU/dt and / or sharp edges can play some tricks on you. So maybe it's a hidden design fault that no one will find in all the mandatory tests and reviews, since it's not covered by the applicable standards.

Mmmmh, should I report this to the manufacturer, or will they think "what does that guy want, he should have let the technician replaced the unit". Usually such kind of technical stuff reporting to a company won't make it to the right people if you don't know an insider.

Once I repaired my JBC station with some hints from their friendly support, found clearly a manufacturing dud (that I could have found without support if I just had looked at the right place), and reported my findings - never got a response.

[med6753]

Do what you would want a buyer to do if you shipped him two of something and he paid for one.

I have to believe this was no accident. These extensions are only good for 560 series. They won't work with 500 series. Very limited usefulness and I suspect he had the two and just wanted to get rid of them.

Edit, but I will contact the seller and see what he says.

I think that you will find that these are not the same items, but are a set, look at the part numbers printed on them, one has 013-0034-00 as the part no., the other has 013-034 and the plug looks different to my eyes.

They are the same. The one with P/N 013-034 is the old Tek part numbering system. P/N 013-0034-00 is the newer P/N.

[tggzzz]

Will somebody please save me from myself. I've got the money but not the time nor the space. I already have £0.99 nixies that I picked up about 15 minutes away from this vendor.

https://www.ebay.co.uk/itm/Solartron-Digital-Voltmeters-A203-A202/153999947342

[bd139]

Already watching that. It’s also in Stonehouse which is prime hiking country and no less than roughly where I was considering moving to. Might mean a day out 

Today is good day. Knee good enough that I managed to hit a 5km run for the first time and come home to Rocky Horror Picture Show

[capt bullshot]

That's only five "digit" nixies within that unit. You'd need to buy two of them to make a proper Nixie Clock <evilgrin>

[Specmaster]

Already watching that. It’s also in Stonehouse which is prime hiking country and no less than roughly where I was considering moving to. Might mean a day out 

Today is good day. Knee good enough that I managed to hit a 5km run for the first time and come home to Rocky Horror Picture Show

Have you got any test gear left to work on this?  Joking aside, its good to see you getting back in there again, good on yah. 

[bd139]

Yeah line drawn now. Hammy stuff gone. Fresh start. Fresh finances. Fresh projects. Clear mind.

Probably not healthy but I erased everything that reminded me of a bad chunk of my life 

[bd139]

Oh I’m not talking about SWMNLBO here. I’m talking about the ham radio thing 

[VK5RC]

Bit of a dilemma...

(Attachment Link)

HP SA. Works well enough, bit inaccurate as can be expected (even though that may just as well be the RF gen) but the display is really dim. This picture makes it look decent because there wasn't much ambient light but it's really no good. So.. ship it of to eBay in an auction or spend some time with the display. May be as simple as dust on the front plastic shield (wouldn't be the first time). I'm leaning to leave it as it is and let the eventual buyer have some fun with it...

I have never tried it but here is a pretty good explanation from someone I would trust. He does contribute on the eevblog forum from time to time (pun intended)
http://www.ke5fx.com/crt.html
I think the lcd kits were mainly for the 856x series, (as I have one - but mine's CRT is still ok)
Good luck
Rob

[bd139]

I'm looking to buy a Raspberry Pi for a home automation project. Unfortunately the 4 GB and 8 GB are so expensive it starts making sense to just buy a small x86 board and set up a proper server able to do more things.

Look for Lenovo ThinkCentre Tiny units or an old Mac mini (core solo/duo). So much better than other turds.

[tggzzz]

Already watching that. It’s also in Stonehouse which is prime hiking country and no less than roughly where I was considering moving to. Might mean a day out 

Today is good day. Knee good enough that I managed to hit a 5km run for the first time and come home to Rocky Horror Picture Show

That part of the world is inhabited by humans, unlike the fens. There's also ten times as much ink (of any colour) on the OS 1:50000 maps Good gliding too

[mansaxel]

Now, non-germanic/scandinavian speakers might need a hand with the translation, so, this is a WAR / PEACE switch. 

Electronics deciding the state of a nation. 

Or, more prosaically, the "battle short" (to borrow a US Navy term) allowing a coastal artillery gun (10,5 cm Tornautomatpjäs M/50) the full, unrestricted field of fire and some other relaxations, among others ignoring the need for a range safety officer pressing the OK button on the surface. In "peace" it was only allowed to fire in small predetermined directions and angles.

The battery is the last remaining of three, and only half of the last has been kept. It is a museum now, and we went there today. Feels good and eerie at the same time to one minute be standing in a postcard archipelago environment, and then instantly walk into a completely man-made techno-world full of blast doors, concrete and oiled machinery under 20 meters of bedrock.

One more item on the bucket list, then. And a nice day out (and in!)

ObTEA: Spotted at least two peices of TE, an Oltronix LF generator and a Tek 400 series scope in the electronics workshop.

[bd139]

Already watching that. It’s also in Stonehouse which is prime hiking country and no less than roughly where I was considering moving to. Might mean a day out 

Today is good day. Knee good enough that I managed to hit a 5km run for the first time and come home to Rocky Horror Picture Show

That part of the world is inhabited by humans, unlike the fens. There's also ten times as much ink (of any colour) on the OS 1:50000 maps Good gliding too

Yes I still have the elevation record for the last time I went out walking that way 

Edit: spot the canal bit

[bd139]

I'm looking to buy a Raspberry Pi for a home automation project. Unfortunately the 4 GB and 8 GB are so expensive it starts making sense to just buy a small x86 board and set up a proper server able to do more things.

Look for Lenovo ThinkCentre Tiny units or an old Mac mini (core solo/duo). So much better than other turds.

I've been looking at those since your earlier posts but unfortunately they tend to be too expensive. If I'm going to spend $300 or more I'd rather build a proper small and frugal server on a modern platform.

Worth looking up the size rankings a bit then. You an get some larger ones for not much more than the postage now.

[med6753]

Oh I’m not talking about SWMNLBO here. I’m talking about the ham radio thing 

I'm pleased to be mistaken.

The SWMNLBO thing, unlike the ham equipment, does not go away overnight or even after some considerable time....as long as they are alive.   

[tggzzz]

Already watching that. It’s also in Stonehouse which is prime hiking country and no less than roughly where I was considering moving to. Might mean a day out 

Today is good day. Knee good enough that I managed to hit a 5km run for the first time and come home to Rocky Horror Picture Show

That part of the world is inhabited by humans, unlike the fens. There's also ten times as much ink (of any colour) on the OS 1:50000 maps Good gliding too

Yes I still have the elevation record for the last time I went out walking that way 

Edit: spot the canal bit

The canal has a long tunnel upstream of Stonehouse.

But I old expect those height gains to take 300m and 20s. Your instruments can also indicate negative height, like this:

[bd139]

Think I’d probably just kill myself quicker in one of them 

Edit: looked up the location and it’s just the other side of selsey common that which is where I was. Nice place 

[Cubdriver]

Do what you would want a buyer to do if you shipped him two of something and he paid for one.

I have to believe this was no accident. These extensions are only good for 560 series. They won't work with 500 series. Very limited usefulness and I suspect he had the two and just wanted to get rid of them.

Edit, but I will contact the seller and see what he says.

If both he and yourself don't want the second one, I know a guy locally who has a 561S. He might be interested. [edit] your package should be delivered today.

And I received an answer from the seller. Yes, it was his intention to send both even though I paid for one.

Ask your friend if he wants one.

And if he doesn't, let me know how much you want for the extra.

-Pat

[Mr. Scram]

Worth looking up the size rankings a bit then. You an get some larger ones for not much more than the postage now.

Idle power consumption is the primary concern and that's where most older platforms fall on their faces. Some oomph when required would be nice too. It's unfortunate Ryzen isn't that frugal at idle yet because I'd happily slap that in a system if it were. Maybe the next die shrink will help that part too.

[bd139]

Worth looking up the size rankings a bit then. You an get some larger ones for not much more than the postage now.

Idle power consumption is the primary concern and that's where most older platforms fall on their faces. Some oomph when required would be nice too. It's unfortunate Ryzen isn't that frugal at idle yet because I'd happily slap that in a system if it were. Maybe the next die shrink will help that part too.

Atom any good? https://www.ebay.co.uk/itm/324188067666

[tggzzz]

Think I’d probably just kill myself quicker in one of them 

Edit: looked up the location and it’s just the other side of selsey common that which is where I was. Nice place 

Or Rodborough common, which is a harmonious place. Have a look at Nailsworth and Stroud.

Be careful when you are driving there; I've seen some scary behaviour.

Normal:



Abnormal:

[Specmaster]

I don't know about you, but I think I'm calling BS on this restoration, at least as filmed 

[bd139]

Think I’d probably just kill myself quicker in one of them 

Edit: looked up the location and it’s just the other side of selsey common that which is where I was. Nice place 

Or Rodborough common, which is a harmonious place. Have a look at Nailsworth and Stroud.

Be careful when you are driving there; I've seen some scary behaviour.

Normal:



Abnormal:

Excellent will have a look around. I saw a house there I can afford which was rather nice a few months back but COVID finished that idea off 

I nearly hit a cow in the middle of Hallingbury Common once in fog in the middle of the night. The buggers will eternally scare me  .

[tggzzz]

Think I’d probably just kill myself quicker in one of them 

Edit: looked up the location and it’s just the other side of selsey common that which is where I was. Nice place 

Or Rodborough common, which is a harmonious place. Have a look at Nailsworth and Stroud.

Be careful when you are driving there; I've seen some scary behaviour.

Normal:



Abnormal:

Excellent will have a look around. I saw a house there I can afford which was rather nice a few months back but COVID finished that idea off 

I nearly hit a cow in the middle of Hallingbury Common once in fog in the middle of the night. The buggers will eternally scare me  .

I've seen them sitting in the middle of the road, and cantering between cars when they realise the rest of the herd has disappeared over the brow of the hill.

Cirencester, pronounced Sissiter, is also not bad. Tetbury feels like a tourist chocolate box.