madbeanpedals::forum

Projects => Tech Help - Projects Page => Topic started by: onthetundra on April 23, 2012, 09:59:24 PM

Title: Low rider DOCT1 issue
Post by: onthetundra on April 23, 2012, 09:59:24 PM
Hey people,

I built my Low Rider and it sounds good but it has one issue.  The DOCT1 is not really functioning.  When I turn all of the other pots down and that pot up I can hear it very faintly and when I turn it down the faintness goes away.  The other pots work normally and the OCT up and DOCT2 are both loud and sound good.  Ive tried replacing all of the IC's and that hasnt helped.  Is there anything that jumps out right away as a possible problem?  Thanks,
Mark
Title: Re: Low rider DOCT1 issue
Post by: stecykmi on April 24, 2012, 04:33:11 AM
since the issue seems to be exclusive to the DOCT1 portion of the circuit, that really narrows down where to look for problems (especially since DOCT2 is derived from DOCT1). personally, i would use an audio probe to trace the signal out (or better yet an oscilloscope, but those aren't available to most).

i would start by probing pin 3 of the DOCT1, you should get only the DOCT1 signal (careful, it'll probably be pretty loud if it's working correctly). If that looks good, check before and after R55 (turn down all the other controls) and make sure you get signal, keeping in mind the DOCT1 pot will affect the signal level around R55.

let us know how it turns out.
Title: Re: Low rider DOCT1 issue
Post by: Vallhagen on April 24, 2012, 06:03:07 AM
As stecykme sais; this should be fairly easy to track down, as it only is DOCT1. I am pretty sure that the problem is the DOCT1 pot. Second guess will be R55. Check your solders.

Cheers
Title: Re: Low rider DOCT1 issue
Post by: harpplayer on April 24, 2012, 03:28:25 PM
Hi! 

Am I the only one getting fuzzy sounds even with all the pots down? (You have to turn up the amp“s volume a bit, but it defintly leaks, and is not as clean as the "natural" sound)