David Collier wrote:
Yes the trigger slope shafts were bent as well! Now straightened.
How did you straighten the shafts? I mean, other than bending them, did you do anything special?
I've got two parts scopes that I'd like to make into one working scope and one parts scope, where the main damage is to the knobs and shafts on the front panels of both scopes (and, like yours, the scopes themselves seem to be in almost perfect working order but for the front panel damage), and I would appreciate any pointers you might have in how to repair the trigger slope switch shafts (I may just have to accept broken knobs, since I haven't found any good source for the trigger level knob, which is what appears to be the common victim of this mistreatment).
The 475 seems to be a remarkably durable instrument, even in the face of obvious physical and electrical abuse. I had thought that it was amazing that my father's scope was in such good working order, but it had been treated with kid gloves and stored in a dehumidified basement for most of its life. One of my parts scopes is clogged with black, sooty dust and covered in something like grey paint, but seems to be in even better working order than my father's scope. And the 475A that I'm currently working on clearly had something happen in the HV section, but the rest of the scope appears to be in very good shape (meaning that other functions seem to be working even though the beam intensity amplifier is busted).
I was expecting all kinds of things to be damaged: blown diodes, transistors, and ICs, dried out and shorted caps, resistors that had drifted out of spec, dim or busted CRTs, etc., but, aside from the 475A (which is certainly delivering on some of those expectations) things have been quite functional, and I deliberately bought the cheapest, most likely to be busted scopes I could find on eBay! It's a testament to the engineering prowess of the folks who designed and built these machines.
-- Jeff Dutky
