[R-390] Caps

[Bob Camp]

Hi

How safe do you feel with a 630 V part? Digikey has 0.1 uf X7R's  for a buck a piece. 

Bob

On Apr 29, 2013, at 6:10 PM, "quartz55" <quartz55 at hughes.net> wrote:

> Yeah, I'd like to see what others have used if not all ODs, especially with the ten IF .1uF as ceramic disk, nearly all of them are bypass caps.  Only C531, audio coupling and  C538 (filament bypass, which could even be a 50V cap) are not bypass caps.  It's not easy to find a .1uF high voltage in even a ceramic at a decent price.
> 
> The five .033uF in the IF are all bypass.
> 
> The two IF .01uF are both coupling caps.  Does anyone use a larger value for C549, the audio coupling and of course the V501 plate to filter C553 is fine as a .01 at 455KHz, no problem using an OD there.
> 
> All the caps in the AF section are audio coupling except the electrolitics.  I've already replaced mine with some metalized ones, but it would be easy enough to fix if I could find one that will fit on the board and not hit the chassis.
> 
> I did one IF in all OD, I got them in, but it's really not pleasant to look at, although I did a bang up job.  I'm just trying to get the price down a bit and mostly make it neater looking and easier to work on. I'm not that concerned about price, but it would be nice not to spend $2/cap.
> 
> I'm also going to replace the 5000pf bypass caps in one of my IF's because something else is wrong and I can't find it.  I'm pretty sure I'm going to use X7R for those. I'm thinking the MLCC look like a good small option for those unless someone thinks not for a good reason.
> 
> I won't whine.
> 
> Dave
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