Test Equipment Anonymous (TEA) group therapy thread

[Zucca]

Congrats dwagon, continue to fix the world!

Yes those plugs go on their knees with time.... I do not like them.

[Zucca]

On other news....

being a Total Commander user for years now, I am approaching a dramatic change....

ComEmu with Far Manager

fresh air for shitty windoz.....

PS: Russian software blows me away... I am missing some russian here.....

[Robert763]

   And So... It Begins.   Pressed the eldest into service today; we did a little clearcutting in preparation for trying to build my workbench space in the dwagon-cave.

   First step once the clutter was hauled off is to get power situated with a GFCI outlet for my TE. 30 seconds into that and...    "Oh cheet, mang..."   A few more minutes of investigation revealed that the top outlet of the duplex is broken out and evidently switched from Ifni knows where the fuck all...

   ...and the lack of ground is evidently widespread and systemic (I can see at least 3 distinct "layers" of electrical work from different eras here), as pretty much every junction block in the basement with the same type of ROMEX run to it as that outlet looks like this.

FML.

mnem

And so... here I am, on the other side...   After several rounds of poking around dusty, cobweb-entangle floor joists and crawlspaces, I finally figured this crazy little bastard out. Originally I thought from the way the Duplex was wired that one outlet was switched from some effing place else in the house I just couldn't find. But after triple-checking the wiring to the side that did light up, I decided to pull these      grounding horrors apart and after testing with my trusty FieldPiece  HVAC DMM, I twisted all 4 grounds together to see if it resolved the open GND, which it did.

That immediately brought another head-scratcher; the other outlet now lights up but shows OPEN NEUTRAL. 

After easily 30 minutes tracing out the other circuit, it finally dawns on me to test the effing outlet with my meter instead of just trusting my Noid-lights. Sure enough, damaged contact in the duplex. Please forgive the ridiculous suicide-cord test leads; they were the only thing I could get to clip on there for the pic.

So... remember kids; any time your handy-dandy xyz tester has you scratching your head... GET THE FUCKING METER!!! There is still no substitute for a good DMM and your brain!

But now comes a whole new misery: Each half of this duplex is connected to a different breaker. Thankfully, both on the same rail so no 240V differential, but I don't know of any GFCI outlet that'll do 2 circuits in one duplex.

I think I've had enough joy for one night; I'm going to bed.

mnem
 

What's with the White to Black connection? has someone put a switch in a neutral?   

[mansaxel]

And so... here I am, on the other side...   After several rounds of poking around dusty, cobweb-entangle floor joists and crawlspaces, I finally figured this crazy little bastard out.

<snip>

But now comes a whole new misery: Each half of this duplex is connected to a different breaker. Thankfully, both on the same rail so no 240V differential, but I don't know of any GFCI outlet that'll do 2 circuits in one duplex.

That would be SO "illegal" in that it violates the assumption of least surprise. Not illegal per se: I just spent some time reading the swedish law, and the by public administration released regulations, that are binding like law, just easier to change.  If you deviate from the Swedish standards (which are neither law, nor regulations) you must document how, why and when the deviation was made, and I guess you must motivate why.

A duplex outlet in Sweden, by design, never can be wired separately; there are bars connecting the two receptacles. A quadruple can, but it is frowned upon.

I would put up two quadruples (in boxes, not recessed), one per circuit, mark them as such and be done with it. That would be least surprising, which is a Good Thing. This being a rental, I'm quite aware of your hands being tied at times, but at least here, the responsibility of the contractor (by law! this is what the law mostly is concerned with) is such that they will sometimes be forced to perform corrective actions on electrical installations to be free of liability.

[Peter_O]

Just popped off in ebay Kleinanzeigen:

Solartron 7081 including cable for 1190.- Euro  (NAWTS):

https://www.ebay-kleinanzeigen.de/s-anzeige/schlumberger-solartron-7081-8-stelliges-praezisions-multimeter/1997294406-168-2472

Oh, that's a nice nostalgic reminder.  :-)

As a young programmer some 30 years ago I was lucky to programm some small GPIB lab code with that one to read out a beam current monitor of the HERA proton accelerator at DESY Hamburg.
https://www.desy.de/research/facilities__projects/hera/index_eng.html


I did the GPIB stuff only, a colleague took over for the complete sofware. I just found an old paper in the web:
https://bib-pubdb1.desy.de/record/172174/files/PUBDB-2014-03606.pdf

When having that setup in the lab, I was wondering about some long time plots of something on the computer monitor that should have beed flat zero but was obivously not. A old electronics colleague passed the hallway, stopped just for one second and commented through the door: "Peter, that one looks like the typical line frequency fluctuation over the day."
There is no substitute for experience.

[Specmaster]

<loads of snipping>

But now comes a whole new misery: Each half of this duplex is connected to a different breaker. Thankfully, both on the same rail so no 240V differential, but I don't know of any GFCI outlet that'll do 2 circuits in one duplex.

mnem
 

Your telling me that a Duplex is what we call a twin socket, but unlike our twin sockets which the incoming supply is shared to both outlets via busbars so that means both outlets are connected to the same breaker, that yours are not made with common connections?  That is a nasty accident just waiting to happen for sure 

[xrunner]

What's with the White to Black connection? has someone put a switch in a neutral? 

And this is just a single, essentially random, house sampling in the entire country ...  extrapolate if you dare want to go there.

[mansaxel]

What's with the White to Black connection? has someone put a switch in a neutral? 

And this is just a single, essentially random, house sampling in the entire country ...  extrapolate if you dare want to go there.

I have realised why the electrickal status of the US (besides being Edisons fault) is in a such sad state.  It is the outlets:



Compare this with the home of cosy, friendly congregation, Denmark:

[Vince]

Somehow the only thing that strikes me in your pictures is that they look blatantly (to me, after just waking up...) like smileys :

- the US socket looks like this :   

.. and the Dannish one looks like this : 

I will go consult a doctor I think....

[Vince]

VARTA Battery :

OK it's been resting for 24H now, so I just measured the voltage again : it settled for 9.4V . Was 10.3 just after charging, and down to 9.75V just 5 minutes later. So it was quickly going for it's final state.

OK so now it's had its first full slow charge since 30 years of storage... discharge it slowly now ? Using my adjustable current source or just sticking a resistor across it ?

I guess it does not matter, as long as current is reasonable. So I will go for C/10 again, and check back on it in 10+ hours.
Will put an ammeter in the circuit (if I go for the current source) so I can see how it evolves and when the battery is starting to struggle.

Googled for how to charge a NiCd battery, found this interesting little article : 


https://www.powerstream.com/NiCd.htm

Well, only interesting for those who were not up to sniff ie, like me. Sure brought back some memories, but a refresher after 30 years can't hurt.  So basically looks like charging at C/10 is extremely IN-efficient because half the energy is wasted, BUT the advantage is that you can make a cheap/simple charger, just a current limited voltage source, and leave it alone... battery won't get damaged if left for too long. However if you fast charge it, it's much more efficient, but it requires careful monitoring of the battery to detect when it's full as you need to stop charging immediately to avoid damage. Two methods following NiCad chemistry apparently : when full it starts a chemical reaction that heats up the battery, so you can detect temperature. Or, when full the voltage also starts decreasing, so you can detect the slope of Voltage over time. When slope goes negative, you know you can / must stop.

Also suffers from the dreaded memory effect. Needs to be fully discharged before charging it, or else you "lose" some battery capacity.

That's OK, discharging is easy enough.. will go do that as soon as I post this...

[Robert763]

In th UK you have to have an independent inspection of the electrical installation before you rent a property.
How well it is inforced or how good the inspections are is open to debate.

On inspections (Electrical Installation Condition Report, EICR) I hd one done prior to a consumer unit ("fuse box") replacement a few years ago. It's not mandatory for this but the contractor insted and they were the only ones available due to a timing deadline created by SWMBO.
It was terrible. They damage decor, put C2 fail codes on things that were not fails and most worringly did not put a C1 (danger present) fail on something that they should have had.
The C1 and one of C2 fail codes related to an electric shower.
They put a C2 code on it because it didn't have an isolator. This was wrong because A. It had an isolator, they just didn't ask where it was and B. An isolator is not required on a modern installation with insulated, conductive sleeved element and RCD protection. Belive it or not some old showers had the bare heating element directly immersed in the water flow in an insulted block 
They also put a C2 on it because phase and neutral were incorrect at the wire feeding it (Red was Neutral Black was live). This should have been a C! and the shower disabled.
Funnily enough the live / neutral crossover was at the "non existent" isolator switch 
All the other C2's and valid C3s (Improvement recommended, not a fail) issues were addressed by the consumer unit changes.
Thay also made a lot of C3 code comments on items that did not meet the CURRENT IET guidance but were compliant with the previous edition. The inspection critiera say that this should not be done fro the specific items.

[mansaxel]

Somehow the only thing that strikes me in your pictures is that they look blatantly (to me, after just waking up...) like smileys :

- the US socket looks like this :   

.. and the Dannish one looks like this : 

I will go consult a doctor I think....

You got it just right. You are properly calibrated.

Edit: without adjustment.

[mansaxel]

However if you fast charge it, it's much more efficient, but it requires careful monitoring of the battery to detect when it's full as you need to stop charging immediately to avoid damage. Two methods following NiCad chemistry apparently : when full it starts a chemical reaction that heats up the battery, so you can detect temperature.

The Clansman battery packs and chargers work to this principle. They have two diodes internally, whose temperature irregularities are enough to detect the heating. To be able to charge the battery in all temperatures, there is one internal and one superficial diode, and the difference between them is used.

I really should get to test my packs again. I've put most of them aside as useless (bought used) as they were nowhere near reasonable voltages and would not charge from the 28 Volt DCCU I've got, and also not from the 12V one. A more clever approach would perhaps prove useful.

[Specmaster]

In th UK you have to have an independent inspection of the electrical installation before you rent a property.
How well it is inforced or how good the inspections are is open to debate.

On inspections (Electrical Installation Condition Report, EICR) I hd one done prior to a consumer unit ("fuse box") replacement a few years ago. It's not mandatory for this but the contractor insted and they were the only ones available due to a timing deadline created by SWMBO.
It was terrible. They damage decor, put C2 fail codes on things that were not fails and most worringly did not put a C1 (danger present) fail on something that they should have had.
The C1 and one of C2 fail codes related to an electric shower.
They put a C2 code on it because it didn't have an isolator. This was wrong because A. It had an isolator, they just didn't ask where it was and B. An isolator is not required on a modern installation with insulated, conductive sleeved element and RCD protection. Belive it or not some old showers had the bare heating element directly immersed in the water flow in an insulted block 
They also put a C2 on it because phase and neutral were incorrect at the wire feeding it (Red was Neutral Black was live). This should have been a C! and the shower disabled.
Funnily enough the live / neutral crossover was at the "non existent" isolator switch 
All the other C2's and valid C3s (Improvement recommended, not a fail) issues were addressed by the consumer unit changes.
Thay also made a lot of C3 code comments on items that did not meet the CURRENT IET guidance but were compliant with the previous edition. The inspection critiera say that this should not be done fro the specific items.

How good the inspections are, currently sums up just everything to do with inspections and enforcements in this country at the moment, just look at the METs refusal to investigate party gate at No 10 

That particular contractor, was he a proper NIEIC registered one or just one of these stupid Part P crash course ones which has more to do with PAT testing than anything else 

[mnementh]

On other news....   being a Total Commander user for years now, I am approaching a dramatic change...   ComEmu with Far Manager   fresh air for shitty windoz.....

PS: Russian software blows me away... I am missing some russian here.....

It's... MS-DOS 11.11 !!! 

mnem

[Robert763]

VARTA Battery :

OK it's been resting for 24H now, so I just measured the voltage again : it settled for 9.4V . Was 10.3 just after charging, and down to 9.75V just 5 minutes later. So it was quickly going for it's final state.

OK so now it's had its first full slow charge since 30 years of storage... discharge it slowly now ? Using my adjustable current source or just sticking a resistor across it ?

I guess it does not matter, as long as current is reasonable. So I will go for C/10 again, and check back on it in 10+ hours.
Will put an ammeter in the circuit (if I go for the current source) so I can see how it evolves and when the battery is starting to struggle.

Googled for how to charge a NiCd battery, found this interesting little article : 


https://www.powerstream.com/NiCd.htm

Well, only interesting for those who were not up to sniff ie, like me. Sure brought back some memories, but a refresher after 30 years can't hurt.  So basically looks like charging at C/10 is extremely IN-efficient because half the energy is wasted, BUT the advantage is that you can make a cheap/simple charger, just a current limited voltage source, and leave it alone... battery won't get damaged if left for too long. However if you fast charge it, it's much more efficient, but it requires careful monitoring of the battery to detect when it's full as you need to stop charging immediately to avoid damage. Two methods following NiCad chemistry apparently : when full it starts a chemical reaction that heats up the battery, so you can detect temperature. Or, when full the voltage also starts decreasing, so you can detect the slope of Voltage over time. When slope goes negative, you know you can / must stop.

Also suffers from the dreaded memory effect. Needs to be fully discharged before charging it, or else you "lose" some battery capacity.

That's OK, discharging is easy enough.. will go do that as soon as I post this...

C/10 is fine  just don't let it get below 7V (1V per cell).
It looks like it has survived. it long sleep. A couple of slow discharge and chare cycles should brng the capacity up.
This is routine maintenence on ni-cads used on aircraft. On most aircraft batteries you have access to individual cell connections (even small packs with D cells). For a capacity recovery and cell balance You discharge until the first cell reaches 1V then clip a 1 ohm resistor across that cell. This continues to discharge the cell but stops it being reverse charged by the main battery discharge current. Next cell to 1V  clip a resistor o and so on.  If the voltage of a cell goes below 0.5V whill still discharging the whole battery the resistor is replaced with a shorting clip. When about 50% of cells are at 1V a 1 ohm goes cross each cell and total battery discharge turned off. Typically leave overnight at this point. Then all cells have shorting clip and left for a day. Clips remved, left for nother 12H before bing put on a C10 charge. capacity chcek and re-charge.
Seems a lot of bother but the batteries are very expensive. Individual failed cells can be replaced. When I started this was all done manually including motitoring and adjusting the current with a rheostat. Now they make fully automatic systems. And batteries are slowly moving to Lithium.

[Robert763]

In th UK you have to have an independent inspection of the electrical installation before you rent a property.
How well it is inforced or how good the inspections are is open to debate.

On inspections (Electrical Installation Condition Report, EICR) I hd one done prior to a consumer unit ("fuse box") replacement a few years ago. It's not mandatory for this but the contractor insted and they were the only ones available due to a timing deadline created by SWMBO.
It was terrible. They damage decor, put C2 fail codes on things that were not fails and most worringly did not put a C1 (danger present) fail on something that they should have had.
The C1 and one of C2 fail codes related to an electric shower.
They put a C2 code on it because it didn't have an isolator. This was wrong because A. It had an isolator, they just didn't ask where it was and B. An isolator is not required on a modern installation with insulated, conductive sleeved element and RCD protection. Belive it or not some old showers had the bare heating element directly immersed in the water flow in an insulted block 
They also put a C2 on it because phase and neutral were incorrect at the wire feeding it (Red was Neutral Black was live). This should have been a C! and the shower disabled.
Funnily enough the live / neutral crossover was at the "non existent" isolator switch 
All the other C2's and valid C3s (Improvement recommended, not a fail) issues were addressed by the consumer unit changes.
Thay also made a lot of C3 code comments on items that did not meet the CURRENT IET guidance but were compliant with the previous edition. The inspection critiera say that this should not be done fro the specific items.

How good the inspections are, currently sums up just everything to do with inspections and enforcements in this country at the moment, just look at the METs refusal to investigate party gate at No 10 

That particular contractor, was he a proper NIEIC registered one or just one of these stupid Part P crash course ones which has more to do with PAT testing than anything else 

They are NICEIC. I was going to report them but a lot of work travel and other commitments pushed it down the prioity list.
They wanted to "fix" bunch of C2's before the consumer unit change. I told them no, I'd do it (they were insisting on another EICR after the CU change anyway). They were within walking distnce of my work office so I did it in person. While walking back I was taalking to SWMBO and she got a call from them on the land line syaing the electrics were dangerous and it was illegal for me to fix them an asked her to authorise repairs. She obviously sid no.
After the CU change they connected up a couple of external isolator switches (for heatpumps the reason for the exercise). Accordin to SWMBO the "sparky" was outside and the electricity switched off. Presumably he did something with he power on. It wasn't  loop test or aanything he'd warned SWMBO that might trip something off.
Of course under the NICEIC approval scheme only the "Qualified Supervisor" has to be qualiified (a couple of NVQ level 3's for domestic) not the drones. 

[AVGresponding]

IMO only time served sparkies should be allowed to inspect/sign off works. Doesn't guarantee competence, but increases the probability at least.

At least I managed to -1 my repair queue in amongst the arguments yesterday. My Fluke 8060A is now fully functional, and without warming up the calibrator for a full check, it seems bang on so far. More details in Discord later.

[ch_scr]

Today was DMTD Rev.3 day:

As can be seen by the changed (and changed again, and again...) resistors, I had to play with the mixer input attenuators
and the gain of the opamp output stage. The SA612 datasheet isn't really communicating which kind of levels to expect
at the pins, at least not in a language I can successfully parse. But with a bit of experimentation, it got worked out.
Also had to supply the opamps with more than 5V (see bodge wires) because the input has a bias close to 5V.
This is the whole mess:

The yellow trace on the scope is the cycle-to-cycle phase difference between the 10MHz references.
(On the counter is the same phase difference, but measured with the help of the DMTD)
The scope measurement shows a periodic jitter of about 2us - not sure what to make of that 
But in general I am very pleased: the new circuit alone has pushed the noise on the counter one digit to the right!
And changing Offset-OCXO's showed the previous one had more noise than the new one, which almost gained another digit! 
Thanks again to Mounty for the OCXO's - they are a lot better than what I had before!
Now I can watch Oscillator phase drift almost by 1/100 of a degree - only downside is,
I don't have Oscillators that are stable like that  (Or rather, the trimpots are too sensitive...)
I can vouch for this rabbit hole, it sure is cozy down here 
Edit: Oops, forgot a zero there  I'll post schematics/layout later on the Metrology DMTD thread.

[mnementh]

What's with the White to Black connection? has someone put a switch in a neutral? 

Sure looks that way; this circuit disappears into a sheetrock wall I have no access to from either side without literally knocking walls down. That is actually why I thought at first the top outlet of the duplex was wired to a light switch. Of course, it is NEVER that simple; this is my luck we're talking about here.

But now comes a whole new misery: Each half of this duplex is connected to a different breaker. Thankfully, both on the same rail so no 240V differential, but I don't know of any GFCI outlet that'll do 2 circuits in one duplex.

That would be SO "illegal" in that it violates the assumption of least surprise. Not illegal per se: I just spent some time reading the Swedish law, and the by public administration released regulations, that are binding like law, just easier to change.  If you deviate from the Swedish standards (which are neither law, nor regulations) you must document how, why and when the deviation was made, and I guess you must motivate why.

A duplex outlet in Sweden, by design, never can be wired separately; there are bars connecting the two receptacles. A quadruple can, but it is frowned upon.

I would put up two quadruples (in boxes, not recessed), one per circuit, mark them as such and be done with it. That would be least surprising, which is a Good Thing. This being a rental, I'm quite aware of your hands being tied at times, but at least here, the responsibility of the contractor (by law! this is what the law mostly is concerned with) is such that they will sometimes be forced to perform corrective actions on electrical installations to be free of liability.

And this is just a single, essentially random, house sampling in the entire country ...  extrapolate if you dare want to go there.

I can make no other comment than that this is the land of "grandfathering" and deregulation. Ifni save anyone who expects those privileged few to actually pay to make something safe; that shitball always rolls downhill to the poor average Joe, no matter what the specific scenario.

In this specific case no, there is no such thing as an electrical inspection when renting a private home to a private party; TPTB did away with that kind of crap long before I was born. To my understanding, the only places that have to meet any kind of periodic inspection are new construction of private dwellings or any time they're added onto, industrial/hospitals/hospitality establishments, and public housing/financial aid housing. Privately owned housing is generally exempt, even when being leased out.

IMO only time served sparkies should be allowed to inspect/sign off works. Doesn't guarantee competence, but increases the probability at least.

I agree... however, then you have the problem of aging homes like this one, where we've been through essentially at least a half-dozen major revisions to the electrical code. To refit the whole house to current code would, in this case, require some pretty extensive demolition/remodeling.

It's really a horrible double-bind, particularly given the expense of hiring a decent & licensed electrician due to the cost of staying certified, liability/accidents & omissions insurance, and even, in some locations, requirement to have separate workman's comp as the electrician is their own employer.

I can get that it's unreasonable to try and apply Industrial-grade electrical standards to a near-century-old private residence; but fuck... there should be some better middle ground where this work can be done without mortgaging the next 3 generations.

mnem
dwagon caught in the middle*

[mnementh]

You're telling me that a Duplex is what we call a twin socket, but unlike our twin sockets which the incoming supply is shared to both outlets via busbars so that means both outlets are connected to the same breaker, that yours are not made with common connections?  That is a nasty accident just waiting to happen for sure 

   
Ehhhh... that's a wiring convention over here. Duplex outlets are made so that you can break out the bus connections between the two halves; the intent being that the top outlet can be reserved for a floor lamp across the room to be switched at the doorway. In principle, not a bad idea if done correctly.

 This is usually done by breaking only the hot bus bar out in cases where the power comes from the box with the receptacle. A single run of 12/2 to the switch then is all that's required to put the switch in circuit; but it does mean that you have a white wire carrying hot to the switch. Over here convention is to look for a switch whenever you see that; real sticklers (like old man Arcangeli) will tag these white-carrying-hot wires with colored tape or uniquely numbered wiring tags. Another "correct" approach would be to use 12/3 and deadhead the unused neutral wire; I've seen that like 3 times in my entire life.

   

Where some real BS arises is the actual wiring in the box. Common "wrong" approaches are to either use a commercial-grade duplex with screw-clamp back-wiring and put both wires under that one screw, or worse, a residential-grade outlet with hot side-wired under the screw and white-carrying-hot to the switch in the backstab port. 

It always seemed to me that there is no good reason why one shouldn't be able to safely put two conductors under a single screw on screw-clamp type outlets like the one above; that kind of terminal self-levels and actually clamps better if there is a conductor under both sides. But to my knowledge, that is not to code; I suspect mostly because it requires the sparky or wannabe sparky to know the difference between the many basic types of receptacle, and to not just buy the 89¢ duplex every time.

For my part, I think I'm just going to repair the ground fault and close up that box, then replace the faulty duplex with a good industrial-grade one wired exactly the same as it is now. I really don't dare do anything more.



GFCI for my TE can be implemented in something external like this; not my preferred solution, but I mostly already have what I need to do it.

mnem
*trying to back slowly away from the sparky-fustercluck*

[mnementh]

Somehow the only thing that strikes me in your pictures is that they look blatantly (to me, after just waking up...) like smileys :

- the US socket looks like this :   

.. and the Dannish one looks like this : 

I will go consult a doctor I think....

This is pretty much exactly how I feel after trying to figure out the wiring in this old house.

mnem
doctor, doctor, gimme a clue...

[mnementh]

And so... here I am, on the other side...   After several rounds of poking around dusty, cobweb-entangle floor joists and crawlspaces, I finally figured this crazy little bastard out. <snip> But now comes a whole new misery: Each half of this duplex is connected to a different breaker. Thankfully, both on the same rail so no 240V differential, but I don't know of any GFCI outlet that'll do 2 circuits in one duplex.

That would be SO "illegal" in that it violates the assumption of least surprise. Not illegal per se: I just spent some time reading the swedish law, and the by public administration released regulations, that are binding like law, just easier to change.  If you deviate from the Swedish standards (which are neither law, nor regulations) you must document how, why and when the deviation was made, and I guess you must motivate why.

A duplex outlet in Sweden, by design, never can be wired separately; there are bars connecting the two receptacles. A quadruple can, but it is frowned upon.

I would put up two quadruples (in boxes, not recessed), one per circuit, mark them as such and be done with it. That would be least surprising, which is a Good Thing. This being a rental, I'm quite aware of your hands being tied at times, but at least here, the responsibility of the contractor (by law! this is what the law mostly is concerned with) is such that they will sometimes be forced to perform corrective actions on electrical installations to be free of liability.

I know I addressed this already, but...

The odds are that the contractor who did these is long-dead, and I believe at one time it was supposedly considered acceptable to use the box to connect the ground conductors as done here.

As for the outlet itself... I actually did have a wild hair notion to do something similar in a single oversized 2-gang box. But then I realized all the misery I could be in for if I made such changes, and decided it was better to limit my own personal exposure.

mnem
 

[TERRA Operative]

Well, one more TDS754D scope lives to see another day. It's working quite well.

Another is on the bench now, trying to figure out why the display has decided to go black and white, even after replacing the CRT, CRT PCB and the main processor board one by one... It was colour then it wasn't.   

[AVGresponding]

IMO only time served sparkies should be allowed to inspect/sign off works. Doesn't guarantee competence, but increases the probability at least.

I agree... however, then you have the problem of aging homes like this one, where we've been through essentially at least a half-dozen major revisions to the electrical code. To refit the whole house to current code would, in this case, require some pretty extensive demolition/remodeling.

It's really a horrible double-bind, particularly given the expense of hiring a decent & licensed electrician due to the cost of staying certified, liability/accidents & omissions insurance, and even, in some locations, requirement to have separate workman's comp as the electrician is their own employer.

I can get that it's unreasonable to try and apply Industrial-grade electrical standards to a near-century-old private residence; but fuck... there should be some better middle ground where this work can be done without mortgaging the next 3 generations.

mnem
dwagon caught in the middle*

Here at least if something was compliant with the current code at time of installation, it doesn't have to be replaced until it's no longer serviceable.

Heading off to Discord, which is quite harmonious, ironically enough...