Also I see you mention variable power source. what power specification would i need for this amp ?
Not a very big one as you only need it for trouble shooting. Make sure it has a current meter so you can check the current flow while increasing the voltage.
And ? Is it AC voktages that it privides?
I am sorry i can’t help you this way if i have to ask twice for everything ..,,
I am sorry i can’t help you this way if i have to ask twice for everything ..,,
Thanks for the pictures. The rough and dry looking resistors are metal oxide types and that is actually a normal appearance of them They are good at withstanding heat.
Reading on and it sounds like you have other problems if this is a 120 volt unit that has been run on 240 volt mains. Essentially all the supply will have been almost double what they should have been. That's not good.
Before you do anything you need to ask yourself whether this is worth expending time effort and money on. If we say it has been overvolted then you are probably going to have a lot of work to do. There could be significant damage in various areas.
You also have to consider how you would ever use the unit if it is fixed. Does the transformer have mains tappings for 230 (240) volt for example.
Reading on and it sounds like you have other problems if this is a 120 volt unit that has been run on 240 volt mains. Essentially all the supply will have been almost double what they should have been. That's not good.
Before you do anything you need to ask yourself whether this is worth expending time effort and money on. If we say it has been overvolted then you are probably going to have a lot of work to do. There could be significant damage in various areas.
You also have to consider how you would ever use the unit if it is fixed. Does the transformer have mains tappings for 230 (240) volt for example.
Just looking at the manual. The transformer is shown as a single primary which means it would need a suitable step down transformer... this I'm afraid just isn't economic and I also think it is going to be far to ambitious a project to restore it given what has happened.
I have already contacted suppliers with equivalent reproduction parts that are suitable according to the manuals
At this point your biggest question is whether you feel you have the ability to work on this. Don't underestimate this. Given that it has been subject to twice its nominal supply voltages there could be quite a few problems that have been caused.
This is just an example of a step down transformer. You would need something at least in the 300va region I would think. Look at the price and ask whether you really want something like that to be alongside the amp somewhere when it is in use.
https://cpc.farnell.com/tacima/sc54...20v-500va/dp/TF00912?st=step down transformer
There must be a 240 volt version of this amp somewhere. Maybe look for a scrap one if only to take the transformer from.
(To repair this it needs to be worked on using its own power supply rather than external DC supplies as there are multiple voltage rails within the amp)
Hi SoundAmp,
I just had a look at this thread. Mooly is correct in everything he has posted thus far.
I was authorized warranty for this brand and have a lot of experience, including 220V to 110V conversions and the other way. A step down transformer is the only intelligent solution and one heavier than what you might think as a minimum is suggested to keep the voltage bounce to a reasonable minimum.
You may have a lot of work ahead, but as long as the transformer is okay you have something worthwhile to repair. I would highly recommend you use an AC variac to troubleshoot and repair the amplifier, never increase the applied voltage beyond 120 VAC. DO NOT attempt to use a "dim bulb" tester.
-Chris
I just had a look at this thread. Mooly is correct in everything he has posted thus far.
I was authorized warranty for this brand and have a lot of experience, including 220V to 110V conversions and the other way. A step down transformer is the only intelligent solution and one heavier than what you might think as a minimum is suggested to keep the voltage bounce to a reasonable minimum.
You may have a lot of work ahead, but as long as the transformer is okay you have something worthwhile to repair. I would highly recommend you use an AC variac to troubleshoot and repair the amplifier, never increase the applied voltage beyond 120 VAC. DO NOT attempt to use a "dim bulb" tester.
-Chris