I don't work on audio equipment very often, so this may be an easy fix for some of you. I have an Optimus STA-900 Receiver with no sound, protection light stays on. If I trip the relay, I do get sound. The relay is good. The output transistors check out fine. A schematic would be helpful if anyone has it. Chad Griffiths TV/VCR Schenectady, N.Y. ***************************************************************************** Lost Password: http://www.tech-assist.org and select "Login Problems?". Email Archives: //www.freelists.org/archives/techassist/