All,
I was given some guidance over on the Tek Scope Yahoo group on a test to run to see if the channel 1 trace is getting a position signal from the A5 board. Basically it was to check the signal at pin 17 on the channel 1 and 2 preamps. This pin receives position control from the A5 board and varies with the position control on the front. The voltages varies the same when I adjusted the vertical position controls for both channels. So with that said, it looks like the channel 1 preamp has an issue.
So, ignoring the fact I needed to go to bed, I removed the little shield over the solder connection on the channel 1 preamp, unsoldered the connection, then removed the nuts holding the preamp to the circuit board, installed the replacement preamp, and put it all back together. Plugged it in, and turned on the power. Low and behold, I now have a channel 1 trace! It moves with the position control and everything. I hooked it up to the internal cal post, which is supposed to measure .4volts, and the display said it was .43volts. Close enough for me tonight. Anyway, It appears that I now have all four channels working.
I still have to change out the power supply caps, but that can wait until a later date. Now I just need to learn all of the capabilities of this scope, and of course, I have the two 1465's to see if I can get back into service. The fun never ends.
Mitch