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Old 03-23-2019, 08:18 PM
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AlanInSitges AlanInSitges is offline
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Join Date: Nov 2017
Location: Sitges, Catalonia, Spain
Posts: 446
I'm just going to add to this thread so I don't stink up the whole forum with dumb questions. Not talking about video anymore!

I am replacing a few of the capacitors in the vertical section while I have this thing's guts up on its chest.



One part in particular Mouser didn't have in stock, and I'm wondering how critical the capacitance is. I'm talking about C5 in the image above. As I understand it, the frequency of the vertical oscillator will depend on the rate at which that capacitor charges and so if I replace it with a substantially different value, I'm going to be way off frequency. The one in the set is .0015 at 1000V, the manual calls for .0015 at 1600V, and the closest I have on hand is .0068 at 1600V. Is a difference this great possible to compensate with vhold control? Or should I just order the right part?

The other doubt I'm having is about C13. I replaced it with the correct value but in the process realize that there is also a .1uf part tacked in parallel underneath the PCB that I'm certain was done at the factory - there are a slew of these in various places. That raises the capacitance an order of magnitude at the same place in the other half of the circuit. If that's the case, then my .0068 shouldn't be such a big deal, I guess?

If you're wondering why I don't just try it, well, it's going to be a big deal to get the PCB loose and change it, and I really would rather only do it once.

As always, thanks!
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