New to this forum,, thanks for letting me join. I recently bought a PL 200 Series II amplifier. It was listed in as is condition so I expected it to need work. It has been worked on previously as some of the output transistors have been changed as well as some of the internal wiring.
I disconnected the two amplifier boards and the good news is the power transformer is working and there is no rust or corrosion on the case. I've downloaded the service manual and reviewed the schematic and I've decided to replace the circuit boards with a design of my own. I'll reuse the heat sinks and power transformer and maybe the output relay, but everything else will be replaced. I've built a breadboard front end and driver stage and have started testing it. It uses a cascaded differential amplifier with a current source load front end and a CFP output stage. I'm not sure how much the supply rails will sag under load, but I expect at least 150 watts RMS out.
Has anyone modified a 200 series 2?
If so what did you do?
Thanks!
I disconnected the two amplifier boards and the good news is the power transformer is working and there is no rust or corrosion on the case. I've downloaded the service manual and reviewed the schematic and I've decided to replace the circuit boards with a design of my own. I'll reuse the heat sinks and power transformer and maybe the output relay, but everything else will be replaced. I've built a breadboard front end and driver stage and have started testing it. It uses a cascaded differential amplifier with a current source load front end and a CFP output stage. I'm not sure how much the supply rails will sag under load, but I expect at least 150 watts RMS out.
Has anyone modified a 200 series 2?
If so what did you do?
Thanks!
