1M pulldowns in place & STILL popping!?!

[Gus]

Something I forgot to post.  I don't think of a pulldown resistor on the output cap as an added thing thats good design I was posting more about the input cap.  I think sometimes an input cap  having a resistor to ground on the input  side causes more of a DV DT or DI DT rate of change than just letting it float.

[Doug_H]

;lkj

[RDV]

I've never used a pulldown on the output.



RDV

[Lonestarjohnny]

I had to pull my last build apart to see what I did that made mine not pop when switching, because i have an Eighteen that's popping when switched, the difference i see is, Both have 1 meg pulldowns at the input cap, the 18 i'm making/braking the B + to the LED, On the 808 Clone i'm M/B the neg side of the LED, and I'm useing a Cliff's 3PDT switch where as the 18 has a Taiwanese Blue, I'll change it around and see if i get any popping.
Plus i just noticed from reading Gus's thread that I have a 200uf Cap on the rails of the Clone and only a 47uf on the Eighteen, this I'll also change.
Johnny

[puretube]

anyone noticed yet, that a circuit-simulator refuses to work,
if an input- or output-cap is not "terminated"?
(in fact, it won`t work with any floating capacitor...).

[Lonestarjohnny]

Made the change's, was still getting a slight pop, not as pronounced as before but it was still in there, so i changed the high dollar , paid 16 bucks for the cliff's switch a year or so ago, and now it's quite when switched, i have some more of the cheaper Taiwanese switches that i'll be useing next, hope they are not all this way, hopeing maybe just this 1 was bad.
Johnny

[puretube]

http://diystompboxes.com/sboxforum/viewtopic.php?p=110966#110966

http://diystompboxes.com/sboxforum/viewtopic.php?p=138205#138205

it is mysterious, sometimes...

[Lonestarjohnny]

Thanks Ton, Good threads,
Johnny

[Doug_H]

;lkj

[puretube]

quite sure, there`s a reason for that...
in tube circuits, you also need a return path (mostly lower than 22M)...

[Lonestarjohnny]

Except when it's a Floating Ground !
Johnny