A local repair shop changed owners some time ago. In the process I received their Phase Linear file. They must have been an authorized repair center form the beginning base on the documents I've seen. I stumbled across a service bulletin recently that dealt with silpads. Thought I would share it. See the attachment. The ones that they mention in the bulletin are the pink silicon rubber types. Later P/L changed to the Berquists. I personally have never had issues with silpads. Apparently there were some people who got carried away and over tightened them. Never try to reuse them when outputs are changed out.
Recently I had occasion to do some thermal testing to see how the bias responds as the amp heats up. I got the case temperatures of the outputs up to 80C (176F). What was surprising was, on each of the 4 heatsinks, the second output form the top was 5C hotter than the top one.
Recently I had occasion to do some thermal testing to see how the bias responds as the amp heats up. I got the case temperatures of the outputs up to 80C (176F). What was surprising was, on each of the 4 heatsinks, the second output form the top was 5C hotter than the top one.
