Oscilloscope

Well the main task for today is to fix the oscilloscope.  It was out of focus and you couldn't refocus it.  Thanks to Google and the EEVblog, I found the problem with my scope.
https://www.eevblog.com/forum/testgear/tektronix-2221a-focus-problem/
https://www.eevblog.com/forum/repair/tektronix-2213a-repair/
My scope is a Techtronics 2213A.  Turns out there is a string of resistors in the focus control section that start to fail over time.  I replaced them, and the focus is as good as new :)

I took some pictures of the boards and their numbers that came out of the FT-101F, so that I could look them up for incompatibilities.

I also had time to recap the regulator board for the FT-101E that is currently on the bench.

I may have to buy transistors to make the crystal calibrator work again.  More investigation will be needed...


























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