All,
I am new to this site. But like you I am an AUDIOHOLIC ! I have a Yamaha MX1 power amp that I have been working on for a couple of weeks. It took a lighting strike, but did not take out any of the power supply components. I have repaired the main boards with sucsess, the protection board is fine. Everything checks out by the schematics EXCEPT the voltage stage of the unit. What I get is the supply voltage to the board (+/- 73 volts and about the same at the signal output. The rail voltage is also the same. I have replaced all bad transistors, resistors and diodes that I find. Maybe the muting transistors or the two 2sk 389s that are on the board? any thoughts
I am new to this site. But like you I am an AUDIOHOLIC ! I have a Yamaha MX1 power amp that I have been working on for a couple of weeks. It took a lighting strike, but did not take out any of the power supply components. I have repaired the main boards with sucsess, the protection board is fine. Everything checks out by the schematics EXCEPT the voltage stage of the unit. What I get is the supply voltage to the board (+/- 73 volts and about the same at the signal output. The rail voltage is also the same. I have replaced all bad transistors, resistors and diodes that I find. Maybe the muting transistors or the two 2sk 389s that are on the board? any thoughts