Danelectro PB&J - Total beginner yanking stuff off circuit board needs help..

[GarthVader]

Hi, i just joined... be gentle! 

I'll try and keep this short: i bought a Danelectro PB&J delay a long time ago, and was pleasantly suprised to find out it oscillated. which is completely non-standard.. nobody else's PB&J self-oscillates, and i even bought a 2nd one to confirm it in person. (plus they're dead cheap and sound great).

so i made this thread over on HCFX a while ago and some suggestions were made about changing pot values and removing resistors and whatnot. me being a complete moron with electronics decided to try the "remove this compenent" option since it's easy enough to do and it's worth the risk.

here's what happened:

feedback reduced to 1 repeat only.    no effect on the delay sound, and consistent across the short and long mode and with different delay times. so i've re-attached it again now.

So i'm basically looking for some help in modifying this pedal to take the limiter off the number of repeats so it can self-oscillate like my other one - (video of it 'on the verge' + pics below). the component has 223 written on it.. could i change the value of that.. do you know what that part is called, or where i could by some of them with different value that i could test out?

http://i51.tinypic.com/2a9d2py.jpg
http://i55.tinypic.com/rsh7ic.jpg
http://soundcloud.com/user3184381/glory-box-mess-about

[Taylor]

The problem is that you combined advice from somebody who knew what he was talking about with advice from some people who didn't, unfortunately. Not your fault, but in the future I would recommend getting advice from a dedicated DIY forum for DIY questions.

Soulsonic is right. You want to lower the value of that circled resistor (the one labeled 223 - that means 22k, or 22 kilo-ohms). By removing that resistor you removed the feedback path completely (when you have only one repeat, that means there is no feedback at all, as the feedback path is from the output of the delay chip to its input).

The solution both to your broken pedal and to get it to oscillate is nothing to do with messing with the pots, but to simply solder a smaller value resistor, like 5k, to that position. However, even folks with a bit of building experience under their belt sometimes have a hard time doing SMD soldering, so you should be aware that what you're trying to do is not an ideal beginner project and it will be easy to mess it up, so go slowly and carefully.

[GarthVader]

thanks for the reply, but i think i've stumbled onto what i was after completely unintentionally!

some guys at HCFX suggested jumping a wire from one contact to the other instead, and (with my impatience for more opinions) i went at it. and while i messed up the soldering process i ended up dropping a big blob of solder across the 2 contact-points.. hey presto, amazing oscillations! i got lucky, i know!

there's a video coming..

[GarthVader]

here it is. oscillating PB&J.. stumbled upon by sheer inability..

[slacker]

Cool, sounds great. Using a smaller value resistor like Taylor suggested would let you tune in where on the pot's rotation it started self oscillating, but your big assed blob of solder approach seems to work fine, nice work.

[markeebee]

You probably already know, but Colin at Experimentalists Anonymous (also a member here) has made an art form out of modding PB&J pedals.  There's a long thread with all kinds of mods and tricks here:

http://experimentalistsanonymous.com/board/index.php?topic=491.0