2. analog
  3. 1431788990

HELP HELP - VENDETTA RESEARCH SCP2A FAULTY

I recently purchased a Vendetta Research SCP2a phono stage - before i go on I am 100% certain it was sold to me without any faults, and that it may have been something else that was the problem -
HOWEVER!!!
I have a major problem
I used a step down transformer as recommended by John Curl so that I could run it off UK voltage which is 230.
I got a great sound out of my right channel - as it happened I only wired the ground to the left channel.

I checked the fuses (1 Amp) - but to be sure I went and got some replacements and put them in.

Once back on again there was a very faint signal out of the left channel alone - I replaced the fuses with the originals - just in case - same thing.

I tried it this morning - absolutely no sound at all -
I got a decent step down transformer from Maplins so that there would be ample overload protection.

I have emailed John Curl and await a response - I have also furiously e-mailed a few audio electricians in the UK - does anyone have an idea what the problem may be?

Alternatively is there anyone you know who may be able to resolve this?

Thanks

Lohan
parrotbee

Showing 3 responses by lewm

lewm
6,770 posts
 
I am a little unclear about the recent history. You say you originally heard no problem with the right channel, only the left channel was without signal. And incidentally, you mention that only the L channel was grounded. When you replaced the fuses, did things get worse, in that you lost the R channel as well? It seems so, based on what you wrote.

Have you opened the chassis, at least to see by visual inspection whether there are any loose wires? The fact that only the L channel was grounded should be neither here nor there, because if you're talking about chassis to chassis grounding, the grounds are probably common to each channel. I don't think there is a problem with your transformer, because you would have heard nothing at all or something more catastrophic might have occurred, if the AC voltage coming out of your transformer is seriously off the mark. BUT do you perchance have an AC voltmeter with which you can check it?
lewm
6,770 posts
 
There is a company on the West Coast, the name of which escapes me, that carries a lot of supposedly no longer available transistors, including FETs. I was able to buy the full complement of transistors needed for my 1980-vintage Beveridge amplifiers from them. I will look for the name later today, but you may find it by simply doing a google search on the needed FET, if indeed you need a FET.
lewm
6,770 posts
 
The company you found, is it in California? If so, they're a really good source.
I feel remiss in not thinking about the electrolytic capacitors. By all means, they need to be replaced if still OEM. One can only hope that damage has not already been done to one or more of the FETs.

Last year I bought a Klyne 6LX. I built a new outboard supply for it using an overkill toroid from Antec, and I replaced all the lytics on the audio chassis with ELNA Silmic IIs. I also upped the values of the PS filter caps. Lots of bang for the buck.
More to discover