Simple, no-math transformer snubber using Quasimodo test-jig

Hi guys,
I built the Quasimodo and everything works perfectly.
But I have one question:
If I switch e.g. 100nF across each rectifier diode, how big is CX on the Quasimodo board?
Since I don't have these diodes in the measurement, they have to be included in the CX.
  • 410nF (4x100nF + 10nF snubber)?
  • 110nF (1x100nF + 10nF snubber)?
  • 400nF (without extra Subber-C)?
  • 100nF (without extra Subber-C)?

Are these diodes still useful over the rectifier diodes?
If so, what value? So far I have always used 100nF.

Thanks for the help!

Best regards, Mike
Getting back to using this on a 6 secondary Toroidy Audio Supreme power transformer. Took awhile to get back to using an analog scope, and can't quite get the trigger held off as much as I would like. The first shot is with 100R and the second shot is 12.5R. I think (?) this is in the ballpark (10 ohms or so). This is one of the 24V windings, primary shorted as 120V (parallel). I'll try it with the primary configured for 240V and see if it makes much difference.

And as a reply to Mikey70, above, I don't think there is any value to the old 100nf across each rectifier diode method. I could be wrong however.


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Perhaps. I raised it to 20 ohms. Changing to 240V primary configuration didn't change much. All of this is using the std. C configuration (10nf / 150nf). I'll go with that. The 8V windings were more or less the same, slightly higher, so I'll go with 27.4 ohms for those.