JDinPA17603 Messages: 69 Registered: May 2018 Location: Lancaster, PA
Member
Amp is end of A series A4.
Background 100uf white Mallory cap had split amp had set for number of years. In consult with the owner we decided to replace all of the Mallory caps that were in the amp and then other parts as needed. Long story short - 95% of all components on the board were more than 20% out of tolerance and that was from the stated values. So I pulled up my PC102 schematic and where the schematic showed 3 ea of 25 uf these boards had 4 and no a 25 had not been subbed for a 10 uf or for the 100 uf.
Upon further digging we find we have 25 fixed resistors instead of 23. I've taken shots of the component and trace side of the board trying to trace through but to be honest my head is swimming right now.
The board just says Ross PC102 but like I said totally different from the PC102 schematic I have.
If anyone can shed light on this or provide a schematic it would be a great help.
Thanks in advance.
Old Us Navy Vietnam Vet
Playing for my own enjoyment and irritation of the neighbors.