Quote:
Originally Posted by bandersen
I recall having ringing issues with an Admiral a few years back and ended up adding a filter.
I'll try to dig up my old project thread.
Sources of ringing and possible cures are discussed in this excellent book.
https://worldradiohistory.com/BOOKSH...-Darr-1963.pdf |
Seems like your latest GE restore was ringing too?
I finally got through reading the book you linked to, very good read.
The whole horizontal scan sequence is more complicated than I'd previously envisioned. Basically designed to resonate at the 4th harmonic of the scan frequency to accommodate the retrace staying within the horizontal blanking period. So this ringing we often encounter is really an inherent design feature, more less working more efficiently than it needs to. The damper tube is suppose to dampen the harmonic oscillation during retrace, but it doesn't always do it's job so well, and so we end up with several oscillations when the horizontal output starts tracing back across the screen.