mcintosh amplifer

Hello - I have a mcintosh mc2125, it was working then the next day it stopped. meters still get input and headphones work but no output from the main speakers. toggling the off/on switch does not do it. I believe it is a bad relay on the unit, seems common and many threads about it. I opened...

Just reading Don Eyles memoir of computer programming for the Lunar Module, titled "Sunburst and Luminary An Apollo Memoir." He mentions that amplified 800HZ signals were needed for testing purposes, and that McIntosh amplifiers were selected as an economical solution! He doesn't identify the...