I'm going to have some time to work on the 400 tonight. I reflowed the solder connections on the bridge rectifier, cleaned them up with alcohol, and mounted in the bottom row of transistors. I also received those AGX-5's and have those in. I'm hoping to get through the entire backplane startup procedure tonight.
The instructions say to "inspect all voltages". My plan was to check B+/B- after each row is added. Is there anything else I should be checking as each row is added? Offset? I have two spring loaded clips on my 2-channel o-scope and a Fluke... Where should those be installed on power up? What's the most critical reading when adding in the drivers?