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Dj_Quirk
08-01-2009, 17:40
I have a US version (110V) SL1200 MKII. It was accidently plugged into a 220 socket which promptly blew it. I don't know much of anything about electronics but nosing around in the guts I came to believe that a new power transformer was the way to go (my 1200 is the version without fuses). Any advice, or am I barking up the wrong tree? :scratch: Thanks

jonners
09-01-2009, 18:07
Yes you will certainly need a power transformer of the right voltage, unless the transformer has survived through being protected by a fuse. In that case you could add an external 230V to 110V step-down transformer. However if there are really no fuses inside (which I find hard to believe) there could be much more damage - to ICs, transistors etc.

If you scroll down to the second picture on this page - http://theartofsound.net/forum/showthread.php?t=1020 - you will see two fuses. Don't you have those?

John

Dj_Quirk
09-01-2009, 20:38
I thought it strange as well that I could not find any fuses but after a little research I found that certain models don't have them. On the PC board where they should be there are mounting holes and printing indicating that fuses are to go there but there is nothing mounted in them.

jonners
09-01-2009, 21:15
Was the TT in an OK working state on 110v before it got plugged in to 230V? I think it's very strange that a piece of equipment has no fuses. Are there visible signs of burning, blackening, discolouration anywhere? Was there a smell of burning when it was connected to 230V? Can you test the continuity of the mains transformer windings with a meter - or get someone else to do it?

John

Dj_Quirk
09-01-2009, 22:25
It worked fine. No burning or black spots. I have a meter but I'm not sure how to use it for testing the transformer. Plugging it into 110V flips my apartments circuit breaker so doing any kind of testing while it's plugged in is a no-go.

Primalsea
09-01-2009, 22:57
If you dont know much about electronics its probably a very good idea not to try to fix it yourself. You are dealing with mains circuits which dont leave much margin for error if you know what I mean.

An option might be to speak to Dave Crawley on this forum as he sells a replacement PSU for the 1210. He might be able to tell you how can test it with no mains voltages.

jonners
09-01-2009, 23:08
It sounds like the transformer has a short then, so I think it's died. The resistance of the transformer primary winding should be 100 Ohms or so. You could measure this with your meter: DON'T plug it in to the mains, but just measure the resistance between the live and neutral pins of the TT mains plug with the switch on the TT set to ON. I think you'll find the resistance close to zero, indicating transformer kaput.

John

Dj_Quirk
09-01-2009, 23:27
I tested the resistance as you said. With the meter set to the 200 ohm range it read .2

jonners
09-01-2009, 23:44
OK, there's no hope for that - the transformer's dead. There would be no point spending money on a new power supply until you know whether there is damage to the circuits as well. I think - as Primalsea suggested - that you need help from someone with experience of mains electronics. The circuits could be tested by temporarily connecting up another appropriate power supply, but I don't think I can help any further unless you live in my part of the country.

John