madbeanpedals::forum

Projects => Tech Help - Projects Page => Topic started by: Carlos Barros on March 23, 2011, 03:29:27 PM

Title: Uproar Gain problem
Post by: Carlos Barros on March 23, 2011, 03:29:27 PM
Hi, i've built the uproar and when i turn on the effect doesn't have gain, it's like if i had another clean channel and i've revised the board and all the components and can't find the problem, please someone can help me?


Thanks!
Title: Re: Uproar Gain problem
Post by: bigmufffuzzwizz on March 23, 2011, 03:33:05 PM
Can you post some clear close up pictures?
Title: Re: Uproar Gain problem
Post by: night-B on March 23, 2011, 03:42:42 PM
Have you checked your 3pdt and jack wiring?
Sounds like the problem sits in there...
Title: Re: Uproar Gain problem
Post by: Carlos Barros on March 23, 2011, 03:54:09 PM
Here is a pic from my PCB



(http://i53.tinypic.com/1zb5w92.jpg)
Title: Re: Uproar Gain problem
Post by: Carlos Barros on March 23, 2011, 04:00:18 PM
The tone and volume control are okay, i put the gain pot all the way up and down it does the same like the volumen pot, i really don't know whats wrong! please help me!
Title: Re: Uproar Gain problem
Post by: night-B on March 23, 2011, 04:43:54 PM
I see a lot of place where your solder joints are really really close. Have you checked with the DMM that you don't short 2 traces of the pcb that shouldn't be relied?
Title: Re: Uproar Gain problem
Post by: Carlos Barros on March 23, 2011, 04:47:45 PM
It's all checked, all is okay thats way i don´t understand the problem!
Title: Re: Uproar Gain problem
Post by: bigmufffuzzwizz on March 23, 2011, 05:10:52 PM
Have you tried checking the pot with your DMM to ensure its working correctly. I've sizzled them before and had this problem.
Title: Re: Uproar Gain problem
Post by: Carlos Barros on March 23, 2011, 05:12:12 PM
this night i'll check it, thanks for the tips i'll post if it works later!
Title: Re: Uproar Gain problem
Post by: bigmufffuzzwizz on March 23, 2011, 05:16:54 PM
the continuity and ohm meter functions will aid you greatly
Title: Re: Uproar Gain problem
Post by: Myramyd on March 23, 2011, 06:21:41 PM
It might be the way the light is reflecting on your board but, to me some of those solder joints look like they might be bleeding on to each other. At the least, a lot of those connections are awfully close together. You might want to make sure there aren't connections being made that shouldn't be. You might have a short or a jumped connection where you don't want one. Some spots look a little dubious.

J
Title: Re: Uproar Gain problem
Post by: Carlos Barros on March 25, 2011, 10:59:11 PM
Hi, i've checked all the parts and points on my PCB and i can´t finde the problem, i don´t how to do to make the pedal work
Title: Re: Uproar Gain problem
Post by: jkokura on March 25, 2011, 11:06:13 PM
Carlos,

I can tell from your picture that your soldering job may be the problem here. You've got some places visible where you've obviously tried using a razor to cut and try and separate some parts that may be touching and shouldn't be. I hate to tell you this, but I think you need to carefully use a DMM and Audio Probe to make sure you PCB is properly soldered and all the parts are properly separated.

Jacob
Title: Re: Uproar Gain problem
Post by: Carlos Barros on March 26, 2011, 05:30:31 PM
I'll do that once again, but if i can't finde any problem i don't know what to do anymore!



Thanks!
Title: Re: Uproar Gain problem
Post by: madbean on March 26, 2011, 06:21:21 PM
Carlos, not to beat a dead horse, because a few people have already chimed in: I would check those traces and solders under a magnifying glass. I do this for virtually every build after I solder on the components. Your PCB etch is decent, but obviously there are a few close calls on those traces. I've had solder bridges that were not even visible WITH a magnifying glass....boy those are a pain.

Other than that, we could look at the voltages on your IC and/or trying a different pot on the gain to see if that might be an issue.
Title: Re: Uproar Gain problem
Post by: Carlos Barros on March 30, 2011, 01:58:29 PM
Thank you Brian, i'll see all that things, i've checked the pot and it isn't the problem i'll check the PCB once again and then i'll post the results!


Thanks for helping me!
Title: Re: Uproar Gain problem
Post by: dromilious on March 29, 2012, 08:25:53 PM
Hello.Actually i don't have a gain problem but i need more gain from this.How i could do this ?changing the gain pot maybe ?Also i need more brightness from the tone maybe more mid range.for this i will change c8 and c9 .But with the gain ?