I just got a couple mark3 amps and thus the sudden lot of questions. I wwant to do the minimum amount of modification but want to do the most practical things to make the amps run safe and consistent.
I have replaced the Selenium with an IN4007 and the 2 caps were switched with 100uF 100V caps that look fairly new. No other resistors or caps were added. I heard you are supposed to use a 4.7K in place of the 1K in the bias inside the chassis but so far I see no reason as they bias fine. Let me know if I should do anything else.
I did the .27s and the .1 on the circuitboard.
I am going to do the can cap as soon as it arives. going to so the 80,40, 30 ,20. And use the 30 after the GZ34.
I am posting the circuitboard. When I got it the resistors that look to be 1K circled in red were replace by a 1 Watt 47ohm. This was done before I got them. I am planning on switching them back but have no idea what it is for or if this value effects anything. Please feel free to chime in.
I have replaced the Selenium with an IN4007 and the 2 caps were switched with 100uF 100V caps that look fairly new. No other resistors or caps were added. I heard you are supposed to use a 4.7K in place of the 1K in the bias inside the chassis but so far I see no reason as they bias fine. Let me know if I should do anything else.
I did the .27s and the .1 on the circuitboard.
I am going to do the can cap as soon as it arives. going to so the 80,40, 30 ,20. And use the 30 after the GZ34.
I am posting the circuitboard. When I got it the resistors that look to be 1K circled in red were replace by a 1 Watt 47ohm. This was done before I got them. I am planning on switching them back but have no idea what it is for or if this value effects anything. Please feel free to chime in.