• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

know any GOOD repair guys...

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My dad once joked about an outlet on every stud when a friend built his new house. It was not quite that bad, but has more outlets than a house built before 1970 or so.
Most of the house fires in the 1950s-60s were caused by cords run under rugs to hide them.

I managed to buy a house that was not really grounded when I got it about 1995 . The lot originally had a house that burned down in the 1950s and they moved an old house onto the lot on the 1960s. The owners were general contractors so I an sort of understand why they failed to ground it. I only noticed when I added onto the house and replaced the fairly old circuit breaker panel. No ground stake at the panel. There was a wire clamp on one kitchen pipe but the wire did not connect to anything. The utility people also noted that likely meth people had collected the closest ground wire from the nearest pole so ground was another pole away at least.
Replacing the breaker panel and having two grounding points also resolved so RF interference problems I had with the stereo.
 
A wood framed house with a four foot crawl space just seems to act like an antenna when the closest path to ground is on the second closest pole. I never felt any shocks when touching anything though I never know if I touched a grounded appliance and a water pipe at the same time.

The pole on the street was missing the ground wire going to the stake. Luckily there was a line run down the backside of my and other lots that was not as accessible. In fact one ground is protected by a bunch of miniature plum trees on my lot.
 
If you can afford it that's one way but if you have a fully enclosed mains transformer with the same VA as your power transformer at a voltage of 10volts/15volts output you could put that in series with the live side of the transformer input


Do you mean like this?

What does the zero side of the transformer connect to, and I guess I could also fit a switch to turn it off if not required?
 

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OFGEM is the UK official service for complaints that aren't resolved between the customer and the supplier as regards energy.


UK Power Networks must have done it on your behalf or want you to make an official complaint .


Complain about your gas or electricity bill or supplier | Ofgem


It will be interesting what advice you are given or told by them as customers on my old website weren't always too happy with the outcome .


Americans have a more "forceful " service .


Keep me---or us informed on this as this is something I helped people with in the past.
 
Update:

Mains still ****, went from 237v to 215v today, all over the place and mostly around 220v.

I am going to build a boosting transformer as per Rod Elliot (thanks Duncan) and add 10v or so to the mains. I will put a variac in a box with a VU meter on the final boosted voltage.

The only thing that might be useful is a simple circuit to prevent over voltage, is this an easy thing to do? e.g. my voltage is around 220v I wind 10v on the transformer, and get 230v. Then Mr Power Newtorks finds 237V and I get a rather high 247v, until I notice and turn the transfomer down?
 
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^ Its no way to operate an amplifier.

215 volts is out of spec and the wide variations you see suggest some real bottleneck in the distribution network somewhere.

Its a legal requirement that it be within the prescribed limits so you need to pursue this and get it resolved.
 
You can get away with up to 15 volts increase but no more therefore just use the boosting transformer but leave out the variac just now that leaves out the worry of high over-voltage .


Unless you have a self adjusting voltage stabilizer ( can set a standard voltage ) just do the boosting transformer .


I used to have a self adjusting variac inside a case but I think they are obsolete now.


I dont care who says what---- FILL IN an official COMPLAINT to OFGEM that is the official way to get the authorities to start acting that's how the British legal system works .


If your energy provider cant ( or wont ) fix this you can file for a reduction in costs of your supply as they have broken the contract with you by failing to provide a continuous viable domestic service to your property.
 
yeah - I will file a complaint tomorrow. I will also ring the maintenance team and see what the schedule is for the work. In essence it was reported to be a main station fault that was not able to be resolved by the local sub station. The lady who read some sections of the 9 page report from the investigation (not sure if I have any right to see this in it's entirety?) seemed to suggest that the remedy would be resolved....but with no urgency and also that 215v was still legally compliant even though I told her it was not.

complaint will be filed tomorrow -----> goodnight!
 
Just a quick update to say thanks and to share my latest understanding.

The problem is failed High voltage supply which is down and due for repair by 'network operations'. We are currently on a back-feed (whatever that means), and until the repair is completed the problems will remain.

The schedule for repair is unknown and so I will use the boost variac until normal service resumes....then after that I have even less excuse to build my own preamp owning a variac that is no longer of any other use to me :)
 
"Backfeeding " is usually applied to an electrical generating system that isn't part of the normal public supply system but is locally generated .


It is sometimes used by those possessing an electrical generator to power the house electrical supply but without many safety measures it can be illegal as at least one guy in America electrocuted a network engineer repairing electrical cables externally.


So I take it your utility company has supplied their own local generating system until they fix the fault relating to the network electrical supply.
 
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I've heard that term used when a supply is connected to two local substations at once and actually have first hand experience of that when we had problems with the supply not holding up under load.

The supply to the house (and a few others) was connected to a different sub with a stiffer cable but the existing weedy connection also left for a couple of days at which point they just literally cut the cable further down the road. That was referred to as 'back-feeding'.
 
I hope you get this sorted Tonescout and they are not "stringing you along " as I found many companies are doing in the UK going by the never ending complaints emailed to me by my old website.


Its just getting worse and arrogance has taken place instead of real customer help services.
 
Sounds like they will get it sorted Tonescout.

Backfeeding is usually where they back feed an 11KV to 415V transformer from the secondary side. This will allow them to feed 11KV into a circuit that is isolated from its 11KV source elsewhere. It could be for a number of reasons. Failed transformer, failed switch gear or even downed lines from a storm or tree fall etc. It does mean that the voltage will sag as it has been stepped down a couple of times from 125KV or whatever and then back up again. The distribution people do have to switch around like this now and again for either maintenance or faults. This sounds like a fault. Probably a dead transformer which will have to be either taken out and repaired or a new one manufactured. Don't tend to keep multi MVA transformers lying about.

I'm sure it will be sorted.

Cheers
Matt.
 
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