Author Topic: moderate buzz partially goes away when touching ouput tip  (Read 4375 times)

guitarify

moderate buzz partially goes away when touching ouput tip
« on: July 25, 2010, 02:39:46 PM »
So I completed the NPN Boost on perf after previously getting my feet wet doing it on breadboard. In both cases I had a lot of debugging to do but I honestly think I learned way more then if I got lucky and it worked the first time.
I'm about ready to start drilling the enclosure to box this up but there is still this moderate buzz(too loud to be usable). I found I can partially get rid of it by touching the tip of the output jack. When bypassed the buzz is significantly less and if I touch the output tip it actually gets louder.
I've checked all the ground connections and didn't see any problems. There is a slight pop when turning it on but it's not too loud. The one alteration I made to the circuit was to add 2 output capacitors, .69uf and .1uf on a 3pdt toggle. It seems to work fine and I don't think it's the issue.

Is this amount of buzz normal for an unboxed circuit or are there some things I should check? My breadboard version buzzed the same way.

aron

Re: moderate buzz partially goes away when touching ouput tip
« Reply #1 on: July 25, 2010, 04:02:39 PM »
Hopefully it is just RF. A lot of it will go away when boxed.

guitarify

Re: moderate buzz partially goes away when touching ouput tip
« Reply #2 on: July 28, 2010, 12:17:42 AM »
Boxing it up got rid of about 60% of the buzz. On a hunch I switched guitars and another 30% went away. Seems like my Teisco may have some grounding issues. I think the other 10% may just be power line noise. But it's hardly noticeable now. Over-all I'm really happy with this build and everything I learned. Up next, I just bought parts to go through Small Bears tutorial on breadboarding a fuzz to learn more about biasing and other parts effecting the tone of a pedal. Should be fun!

aron

Re: moderate buzz partially goes away when touching ouput tip
« Reply #3 on: July 29, 2010, 07:11:52 PM »
Great! Good luck!

Aron

lil PopTart kid

Re: moderate buzz partially goes away when touching ouput tip
« Reply #4 on: August 08, 2010, 01:27:27 AM »
Also turning off a lot of the lights around where you are playing will help.  The lights often interfere.  The reason it got worse when you touched it is because you body acts as an antenna picking up even more unwanted noise.