I have two Tektronix scopes: a 485 and a 2465. Both of them need a little TLC, but I'm going to focus on the 485 at the moment as it is non-functional. I'm not an experienced electronics tech, but I'm not a complete novice either.
I really like the blue phosphor of the 485. For the moment the traces will show up, but the traces don't respond to input on either channel. I think the problem lies with the attenuator cards, but I'm not 100% sure thats the only problem. This I know for sure: if I take my signal gen and hook up its output to the place on the vertical amplifier where the attenuator plugs in, the signal is displayed on the scope. Another strange symptom is that on Channel 1, if the impedance is on the 50 Ohm setting, the trace is there, but on the 1 MegaOhm setting it disappears. Any thoughts guys? Have any experience with this sort of thing?
I've taken out the channel 1 attenuator and have it in my hands right now. Where should I start troubleshooting?
Thanks!
John
