[Bear]

I recently bought a craigslist Technics SL 1200 MKII on craigslist and the left channel has extremely low to no output.  I rewired the RCA plugs(switched inputs around first to make sure the issue was at the turntable and not elsewhere in the system), I switched out headshell/cartriges, so the problem must be in the tonearm wiring?  maybe the tonearm circuit board somewhere?   Any experiences or suggestions?

Thanks,
Shane

[Wayner]

Take a digital multi-meter and do a continuity test from the headshell leads to the RCA connectors. I suspect the wire may be shorted out, or the IC from the table is bad. If you take off the bottom cover, you will find the tonearm circuit board and you could do a continuity test from the headshell to this board. I suspect the problem is not in the tonearm, but rather the interconnect cable. Infact, test the other way from circuit board to RCAs and I think you will find a bad conductor.

I'm not eliminating the arm wiring, but I would go for the weakest link (and easiest to repair/replace) and that is the interconnect cable.

If it's an interconnect shield that is bad, you could connect both commons together at the cartridge end, cause they are connected together at the preamp end anyway, and that might fix it too.

BTW, did you swap the left and right channels at the cartridge? Your cartridge might be bad. I just had a Grado Longhorn failure, brand new (for a customer) with an open circuit. So cartridges can get smoked too.

Wayner 

[Bear]

Thanks Wayner,

I did not swap the channels at the cartridge but I did swap to another cartridge headshell combo and still the output was nearly non-existant.  I took it apart last night but did not see anything obvious, I will take a meter to it tomorrow and see if I can identify anything.  Im not very knowledgable with these things though.

Shane

[Wayner]

Sometimes the contacts at the end of the arm (head shell removed) can become corroded. I would try using an eraser from a pencil and try rubbing off the oxide. It could be as simple as that.

Wayner 

[Bear]

Sometimes the contacts at the end of the arm (head shell removed) can become corroded. I would try using an eraser from a pencil and try rubbing off the oxide. It could be as simple as that.

Wayner 

I will definately try that first, to the naked eye everything appeared very clean.  I plan on rewiring the tonearm anyhow, but would prefer to know what/where the issue is before rewiring for piece of mind, if that makes sience..

[mix4fix]

Sometimes the contacts at the end of the arm (head shell removed) can become corroded. I would try using an eraser from a pencil and try rubbing off the oxide. It could be as simple as that.

Wayner 

I bought a used pair of 1200's and one of those contacts was sticking.

I cleaned it with alcohol and fiddled with the particular contact until it pops back into place regularly.

[johsti]

Bear - I think I just purchased your turntable on Craigslist??? not really, but I did just purchase a used 1200mk2 on CL, and am having the exact same problem.  Very weak left signal output.  I've swapped the RCA's around and it definitely seems to be a problem with the turntable.  Did you ever determine what the source of your problem was?

edit - problem fixed with a little alcohol and a q-tip.