RP112 100 WATT COMBO NO OUTPUT
Good Morning, the amp in question when purchased had really low volume with the master on full and channel volume on 10. All the electrolytics have been replaced including the dog house and all the ics and the 2 transistors. There was significant evidence of heat round the valve clips and base. When the amp was turned on after the work being completed the bias reading across both 3.9 resisters was 81 and 86. On resetting a comfortable 25 mv and 26 mv was achieved. When an input was tried there is no volume at all running into an 8 ohm speaker. Measuring voltages on the valve bases resulted in,
pin 3 low position 460 high position 692.
pin 4 - 227
pin 5 - 16
pin 8 - 36.
other pins 0.
Could anybody point me in the right direction on where to check next please, this is the amp from my previous post about the missing component , which Mike helped to discover was a thermal switch. Could this be an output transformer problem although there was output before the cap replacement was carried out,. Many thanks for reading this and fingers crossed.