Pop switching

rocker-D82 · May 04, 2005, 06:22:32 PM

I build a Small Clone from tonepad info. It's sounds good, but I've a "pop" when I turn on the effect. I haven't this problem when I turn off. There's a way to delete it?

niftydog · May 04, 2005, 07:41:14 PM

probably caused by different DC levels between the effected and bypassed modes. There are several ideas to help solve this common problem, one of which is simply to provide a path to ground for the input/output caps to charge/discharge when the switch is activated. This is usually done with a 1M resistor from the cap to ground.

Have a quick search of the forums, there's been heaps of discussion on this topic in the past.

rocker-D82 · May 05, 2005, 01:53:45 AM

I know this solution.
I insert 2M2 resistor by .033 input cap and ground. But for the output, I don't know what is the right way to mount it, because the output signal arrive from a series of 1uF cap and 100k resistor.

Can you see the schematics and tell me where I can solder my anti-popping resistor?

niftydog · May 05, 2005, 02:24:24 AM

usually it's the very last component before the output jack - some people actually solder it to the output jack itself.

rocker-D82 · May 05, 2005, 12:19:45 PM

But if I solder it from output to ground, I do a parallel between 100k output and 1M anti-pop resistor. This will decrease my output drasticaly!

niftydog · May 05, 2005, 08:31:35 PM

1M in parallel with 100k equals 90.9k.

I guess you need to be sure that it's the output that is the cause of the problem. Take some measurements at the inputs and outputs of the circuit to see where the DC is coming from.

rocker-D82 · May 07, 2005, 09:00:40 AM

Quote from: niftydog
I guess you need to be sure that it's the output that is the cause of the problem. Take some measurements at the inputs and outputs of the circuit to see where the DC is coming from.

I solder a 4M7 to output jack from signal tip and ground. I solve partially my problem: popping seems to be less, but I don't delete it!

Khas Evets · May 07, 2005, 01:48:38 PM

The 100K resistor on the output should act as a pull down resistor. I'm not sure why the additional resistor helped. You could benefit from adding one to the input, but you've already done that. Are you grounding the input to the board while the effect is bypassed?

leonhendrix · May 07, 2005, 03:07:05 PM

it might be a electrolytic cap put in the wrong way

i had popping on my scrambler even though all the caps were the right way by the schematic. i found out that this schem was based on the original which had the popping problem and was told that by reversing one of the caps would solve the problem.

leon

rocker-D82 · May 07, 2005, 04:00:17 PM

Quote from: Khas EvetsAre you grounding the input to the board while the effect is bypassed?

Yes!

I solve my problem changing the soldering of 3PDT. I found the new scheme here:
http://www.diystompboxes.com/sboxforum/viewtopic.php?t=32968

I try with 4M7 resistor to output, but it seems to make my effect dummy!!!

I remove this resistor, but with the new soldering I don't have problem!

It's perfect... cool!
We can see my DIY stomp here: http://www.marc-us.com/rocker/pedalmaking.php ...sorry, in italian!

News:

Pop switching