madbeanpedals::forum

Projects => Tech Help - Projects Page => Topic started by: Wedge on November 22, 2010, 08:03:14 PM

Title: Slow Loris Issue
Post by: Wedge on November 22, 2010, 08:03:14 PM
Hey guys, so I'm currently in the process of building a Slow Loris for a friend of mine, and am running into a problem.  I ran a signal tester over the circuit board (one from BYOC, put in signal to input, listen to output from spots on the board), and found that I was getting signal into C9, but no signal out.  I assumed, therefore, that my capacitor was bad, so I ordered another one and replaced it, but the same problem kept occurring.  The one I just put in is a Topmay TCM07 63V 5mm box with a +/- 5% tolerance.  Any suggestions on what I should try next?  Oh, and it's a ver. 1 board, if that makes a difference.

Thanks a lot!
Title: Re: Slow Loris Issue
Post by: jkokura on November 22, 2010, 08:16:55 PM
It looks like that if you're getting no sound after C9 then you've got a bad solder joint. If you replaced the part already, chances are you wouldn't get two faulty film caps in a row, it's more likely to be a bad solder joint. Try reflowing the solder, or perhaps using some rosin to clean it up.

Also, just to be sure, are you checking at the volume pot or at the cap? It could be that the trace between C9 and the volume pot has a break. Could also be that the pot has a problem, but that's very slim. Finally, it could be that the part is bad again, but the odds are very, very, very small.

Jacob
Title: Re: Slow Loris Issue
Post by: Wedge on November 22, 2010, 08:43:42 PM
Well I just tried reflowing the solder, and still nothing - and I'm measuring this right before and after the component - on the solder joint itself.  The input to C9 produces sound, but the output lead/solder joint does not.  Any other crazy ideas?
Title: Re: Slow Loris Issue
Post by: jkokura on November 22, 2010, 08:49:35 PM
No, you can try measuring the cap, you can try jumpering it or using a different value capacitor. Perhaps if you need to replace it try installing some sockets rather than soldering the part in directly. It will be easier to check continuity.

I would really have placed money on the poor soldering job thing I said before. That baffles me. The only thing I can really see it being is simply that - a poor solder joint. Perhaps you need to remove the solder and start over on that joint.

Jacob
Title: Re: Slow Loris Issue
Post by: madbean on November 22, 2010, 09:15:38 PM
That is strange. Try flowing solder directly from the end of C9 all the way to the pad of the volume pot.

Maybe that volume pot is grounding out somewhere.
Title: Re: Slow Loris Issue
Post by: oldhousescott on November 23, 2010, 12:40:22 AM
Brian's right. If you have no output, you've probably got a shorted pot or output jack. Check that the output jack is wired correctly, and that the pot isn't shorted to ground from C9.