building ggg hotbox capacitor question

[9 volts]

Hey there, quick question about capacitor ratings in the hotbox at ggg. Through the clean channel the signal goes from plate through a .022 cap (400v) before hitting the volume which has a few pf capacitors connected to it. Do the pf caps have to be rated for 400v also? I figure since the signal has already gone through the .022 (400v) cap these could be a lower voltage. Yes?

[petemoore]

I figure since the signal has already gone through the .022 (400v) cap these could be a lower voltage. Yes?
  Yes ? ...'ok'...sounds logical...
  But I can't see what you're doing.
  One way is to calculate what voltage the capacitors will see.
  Another is to measure the voltage they will see [as long as that's it].
  A third and less desirable is to stick whatcha got in thar ansee if it blows...
  Fourth and last is post schematics of everything that comes under question.
  PS using larger voltage rating than what the PS is never fails...expensive...space consuming etc.

[9 volts]

Sorry the schem is at general guitar gadgets under hotbox, see link
http://www.generalguitargadgets.com/diagrams/hotboxsc.gif

[petemoore]

  well./..nice effort, it is too large or small to make sense of easily.
  You should read 0.0vdc....on the outside of a DC blocking capacitor in a circuit...
  As long as it 'is on the outside...sounds like it is, comes off a plate output [HV], and goes to a volume control [seems the only electricity you or any further capacitors would see is AC signal...
  And I"m really not certain how that figures into capacitor voltage ratings...ok for me to guess? I guess the peak voltage is what matters, and since this is a 'booster', the AC signal voltage would be small enough that any 'normal' capacitor [say >16v] will be fine there.
  I would guess that the info is available if you can dig it out of it's hiding place, first place to look would be the BOM for the project, but maybe it's in some other 'universal' text at GGG...maybe not too though.
  So hope this helps.
  Unless it's a super strong pre-amp or amplifier, the voltage you'd see beyond a DC blocking cap = signal AC = >10v...don't quote me..

[9 volts]

Thanks Peter, thats what I figured. We'll see what happens. The BOM says all caps are 450v, but given that these are parallel with resistors you'd hope no dc had got to this stage.

[MikeH]

I was just looking at this project recently; is it just me or are the "A" and "B" points reversed between the schematic and the layout?  What I mean is, all the "A" points on the schem seem to line up with the "B" points on the layout and vice versa.