Tektronix 465B: Repair
For engineers analog oscilloscopes are a bit like vinyls and tube amplifiers: Most don’t use them anymore, but if they see one, they think: Nice! And are happy that they don’t have to deal with them on a daily basis ;) However, I bought a Tektronix 465B with a faulty second channel, just to repair it. For this one, I made a quick YouTube video.
Caution
High voltages found inside of analog oscilloscope can cause damage, severe injury or death. If you are not authorized or qualified to work on such devices, don’t do it. I don’t take any responsibility for actions you take or the results of these actions. You do everything at your own risk.
Here is the link (external page, YouTube): https://www.youtube.com/watch?v=QqoxUd-pWKk
After the initial tests with the BAT41 diode I ordered a proper replacement: the 1N5711. Also, I replaced some capacitors, including a slightly discolored tantalum capacitor. Then I powered the scope up and… Nothing. Did I blow it up? As it turned out a cable soldered to the line switch got loose. After solving this small issue the scope finally started doing its job again. Almost at least. I went through large parts of the calibration/adjustment procedure to bring channel 2 up to speed and make it a bit more accurate.