So I picked up an 02 TSL100, when I got it the preamp tubes were original and the power tubes had seen better days.
When I checked the bias when I first got it. Side A read 93mv and side B read 29mv. So I got a complete retube with kt77s. Put all the new tubes in, I watched for run away bias... sure enough it was.
So I pulled the board drilled out pin 5 on all sockets, replaced the 220k with 5.6k.
Replaced R67,R68,R69 with new metal film resistors. Got it all back together, checked the bias again and side A was at 75mv and side B was at 29mv. So I turned down side A to about 61mv and then side B I got up to 61mv but it maxed out the pot.
I want to try out biasing higher where do I start?
When I checked the bias when I first got it. Side A read 93mv and side B read 29mv. So I got a complete retube with kt77s. Put all the new tubes in, I watched for run away bias... sure enough it was.
So I pulled the board drilled out pin 5 on all sockets, replaced the 220k with 5.6k.
Replaced R67,R68,R69 with new metal film resistors. Got it all back together, checked the bias again and side A was at 75mv and side B was at 29mv. So I turned down side A to about 61mv and then side B I got up to 61mv but it maxed out the pot.
I want to try out biasing higher where do I start?