Build Your Own Clone Message Board

Hi people. New user here. Purchased the Lazy Sprocket and the 250+ kit about a year ago.
Built the 250+ easily by following the instructions and very much like the pedal. No problems at all with it.

The Lazy Sprocket is another story. The pedal activates fine, the led lights up but the pots do nothing. I'm not sure where or how I have gone wrong but I am attaching pics for some critique and review, if possible.

Files are attached but I'm not sure if they will show up.
Thanks in advance for any/all help you can offer!

Bill

hi, and welcome Bill!

A question right off the bat: why didn't you solder in the center leg of the trim pot? Doing so would go a long way towards getting her working, I think. Since there's already some solder in the pad, it looks like you should just be able to heat it up and push the leg in.

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Hey Captain! Thanks for the reply. I *did* solder in the leg of the trim pot however, the pedal was still not working so to be sure it was not faulty, I removed it temporarily, taking it out of the circuit.

Was there anything else you saw there that needed attention?

Appreciate your help very much!

B

well, it's hard to tell because the pics are a bit blurry, but it looks like your soldering is a little rough. I'm assuming you've already checked that all the components are in the right places and oriented correctly (if applicable). The first thing to do would be what some of the guys here call the "shotgun" technique - first, make sure all the component leads are clipped short, right to the top of the solder joint. Then, using a hot, clean, & shiny tinned iron tip, go around the board and reflow (melt) every solder joint for a few seconds - just long enough to heat it all the way thru. If the hole isn't completely filled with solder, add a little bit. Wipe and re-tin your iron tip frequently. When you're done re-flowing, each joint should be shiny, not dull, and shaped like a hershey's kiss. No blobs, bubbles, etc. Use a toothbrush and a little rubbing alcohol to clean away any excess brown flux that has stuck to the solder side of the board. Then give her another shot.

If that doesn't do it, we'll probably need some pics that are in better focus. But as long as all the parts are in the right spots, the old "shotgun" reflow is very likely to get her going!

Another thing to keep in mind is that this circuit isn't used to high-gain modern humbuckers - so the sensitivity will have to be set carefully or a hot incoming signal will overpower the gate and you won't hear any swell. Even the Texas Special single coils in my tele are a little too hot for this thing. Use the max attack time when testing, too - it can be a subtle effect at short swell times.

Hope that helps!

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Thanks for the lengthy reply Captain. OK, "shotgun" reload it is. I'll give that a try and then see how it goes after-the-fact.

It's weird because the pedal powers on and I don't lose any signal when it is engaged, it's just that, there is zero effect whatsoever. And yes, I did try it with a variety of guitars.

OK, thanks again and I'll get back to you once I've tried your trick.
Cheers -

B

Try this: set Sensitivity to about 9:00 and Attack to full CW. Now adjust the trimmer as you play a note and see if you can dial it in.

I checked the components I could see and all resistors and diodes are good. Orientation of components is good too, but I would double-check values for caps and transistors.

Have you got anywhere with this?

It isn't really weird if you get full signal but no effect in active mode because the direct audio path through the pedal is through two unity gain buffers.

Broken down into circuit elements the Lazy Sprocket consists of the direct audio path (T1 & T2 + associated components), a gain boost and envelope follower (IC1, T3,4 & 5 + associated components) and a gain control element (T6 plus other bits).

You know the direct audio path is probably OK so its something in the other circuit elements that isn't working - is the op-amp gain boost producing a healthy output to drive the envelope follower? does the envelope follower produce a control voltage to drive the FET gain control, is the FET biased properly and is it functional?

What you could try is connect a multimeter to the junction of R14 and C9 and see if you can see any sign of a change in voltage when the input of the pedal gets a signal (strum from a guitar for example).