Dead/quiet channel on Dual Turntable - cartridge?
Jul 8, 2013 at 10:35 AM Thread Starter Post #1 of 6

Tetromino

Head-Fier
Joined
Aug 22, 2007
Posts
90
Likes
0
I've just finished recabling a Dual CS503-1 because one of the channels was dead. I have continuity from the start of the tone arm wires right up to the RCA connectors but the problem persists. I have reversed the Left & Right connectors to make sure it is the turntable not the amp (tested with two amps). Seeing as I've ruled out the wiring does this mean there is a problem with the cartridge/stylus? And how would I go about finding out short of buying a new cartridge? It has the stock Ortofon/Dual DN249E still, not sure about stylus condition or if it's ever been replaced. (The one channel I have sounds fantastic!)
 
If I set the balance all the way over to the dead channel, I do get a quiet signal, but nothing at all when balance is normal.
 
Many thanks
 
Edit: I just measured the resistance between the two sets of pins on the cartridge (all wires removed). My working channel reads 14.4 M ohms while my faulty channel is 14.4 k ohms. Is this significant? Sorry for electronics noobishness
 
Jul 8, 2013 at 12:04 PM Post #3 of 6
Tetromeno- Are you saying one channel measures -14.4 MEG??-and that's the GOOD one?-The only  time values like that were used were in the distant past in CERAMIC carts.You must have measured it wrong. Moving Magnet cart should look into an impedance of -47K ohms so you would need to look into an impedance of MORE than -14.4 MEG - Never come across that before.a Moving Coil  cart -which has a VERY low resistance into a bit higher than the value of it-although yes it would still work into -47Kohms. This sounds like a collapsed needle holder  damaged by banging on the deck OR damage to the fine coil wire.. If MM magnet damage or movement.
 
Jul 8, 2013 at 12:09 PM Post #4 of 6
Update: Connected each pair of tone arm wires together with a crocodile clip and measured the resistance across the pin and shield of the RCA connectors. Both returned identical results of approx 200 ohms. I am now fairly sure this is a cartridge issue and not the result of my wiring job! Does anyone else have any thoughts on this?
 
Jul 8, 2013 at 12:29 PM Post #5 of 6
Quote:
Tetromeno- Are you saying one channel measures -14.4 MEG??-and that's the GOOD one?-The only  time values like that were used were in the distant past in CERAMIC carts.You must have measured it wrong. Moving Magnet cart should look into an impedance of -47K ohms so you would need to look into an impedance of MORE than -14.4 MEG - Never come across that before.a Moving Coil  cart -which has a VERY low resistance into a bit higher than the value of it-although yes it would still work into -47Kohms. This sounds like a collapsed needle holder  damaged by banging on the deck OR damage to the fine coil wire.. If MM magnet damage or movement.

 
I'm guessing I should just replace the cartridge?
 

Users who are viewing this thread

Back
Top