>I am building the KPA 100. I have just tried the resistance measurements on >page 41 of the Alignment and Installation. Sounds like you are maybe running into the photoelectric effect on the PA transistors too. Do you have a strong light on the workbench? http://www.ac6rm.net/mailarchive/html/elecraft-list/2003-11/msg00574.html -- Ward / KG6HAF