Sunday, October 24, 2010

I've been really dragging my feet about burning in the caps on the RCA oscilloscope, seeing as how they are dated late 1964 for manufacture and I'm not doing the recap, rather hoisting it off on someone else. So I've been tiptoeing around the machine a little bit, keeping my heavy hand to myself.

In pondering the guts, two things are obvious. A) this machine has been subject to an impact of sorts at one point in the past 46 years:

B) the wire which broke free was essentially under tension and I'm willing to embrace the theory that the wire gave out when the impact occurred. You can see visual signs of oil staining on the wafer at which the wire was bent. I believe such leeching is inherent in the chemistry of the plastics, which in and of itself can be considered alarming.

Sticky wires sort of comes with the territory though, I do minimize contact with them when they are in this state, typically by leaving them be. Unless they've collected organic matter on the sticky surface I've not seen first hand evidence of voltage insulation failure, so... it's filed in the leave well enough alone category.

The fix for this unit entailed simply stretching the wire, which, due to the impossibility of directly applying that concept to actual wire I ran a leg off the terminal using a lead clipped from another component.

I'm happy to report that at a little over 80% wall voltage the scope is showing trace!

The hawkeye's amongst you will notice that the horizontal is far from true, I'll adjust clamp positioning once it's up to full voltage.

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