I got a Denon DP-60L in the shop for a speed control issue. It went hyper-sonic after a few minutes of run time.
Turns out this is a common failure mode for this 'table, given all the youtube videos about it.
Short story long, I bought a complete board on eBay to do a board swap.
The board in my 'table had three locations of unpopulated parts including the power supply, which is located off-board.
The donor board had all those locations populated, including an on-board power supply, which would have added a lot of noise.
Some of the wiring was different. Different enough to make me hesitate to perform a major retrofit.
There were too many unknown modifications I would have needed to consider before using this board.
I attempted to sent it back. The seller balked. Was I wrong for claiming the board wouldn't work?
Had I had attempted to jury-rig it in and smoked it, I would have owned it. At an almost $200 loss.
I later found out this was an early Japanese version of this 'table. Later (US export) versions used a simplified design.
The service manual offered little in the way of help in this area other than the schematic and board layout.
With nothing to go on, I stared tracing from the pickup head onward, replacing the cheap components until I got to the offending parts.
Several caps around IC-1 (TA-7122BP) were leaking, they got changed, Though they measured open, it didn't solve the issue.
TR1 is a 2SC458 Turns out KSC1815 is a good sub for this part. This ended up being the problem child.
Turns out this is a common failure mode for this 'table, given all the youtube videos about it.
Short story long, I bought a complete board on eBay to do a board swap.
The board in my 'table had three locations of unpopulated parts including the power supply, which is located off-board.
The donor board had all those locations populated, including an on-board power supply, which would have added a lot of noise.
Some of the wiring was different. Different enough to make me hesitate to perform a major retrofit.
There were too many unknown modifications I would have needed to consider before using this board.
I attempted to sent it back. The seller balked. Was I wrong for claiming the board wouldn't work?
Had I had attempted to jury-rig it in and smoked it, I would have owned it. At an almost $200 loss.
I later found out this was an early Japanese version of this 'table. Later (US export) versions used a simplified design.
The service manual offered little in the way of help in this area other than the schematic and board layout.
With nothing to go on, I stared tracing from the pickup head onward, replacing the cheap components until I got to the offending parts.
Several caps around IC-1 (TA-7122BP) were leaking, they got changed, Though they measured open, it didn't solve the issue.
TR1 is a 2SC458 Turns out KSC1815 is a good sub for this part. This ended up being the problem child.