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I've been having some difficulty with this pedal and have never been able to get it working. I got it close to working once, see the previous thread below:
viewtopic.php?f=19&t=54474

The outcome of that last thread was that it was working but I was getting some noise when turning a knob on the pedal. It's been so long since I've actually looked at it that I can't remember what knob. Anyway, I started working on it today by simply sticking it back in the box and turning it on, and it seems that I have a new problem. It only works in true bypass and the led doesn't come on at all. My sense is that the pedal is not getting power.

Here's what I did:
I re-wired two of the dc adapter wires, as they seemed a little loose, and I cleaned up the board as best I could. Hence the new pics and the new thread. I've tested the pedal by completely putting it back in the case, as well as having the parts and pcb hang loosely out of the case while it's all hooked up. I did this because I was uncertain if the pedal was shorting when squeezed into the box and all the nuts where tightened up.

Any help would be greatly appreciated.

More pics

last pic

Do you have access to a multimeter and know how to use one?

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Yes indeed

Hey Duhvoodooman,

I read through the previous post where you were helping with this problem and ran through the same tests again. Here are the results.

I tested my 9v batter with a DMM and got a reading of 8.63v.

With the 9v battery connected to the pedal and an instrument cable inserted into the input jack, I tested the following points of the circuit with my DMM set to a 20V range setting. I made sure that the black probe of the meter was grounded:

Top leg of the 4.7K resistor next to the LED - I got an 8.75v reading
The square (bottom) solder pad of the LED - I got an 8.75v reading
The bottom leg of the 1N4001 diode at the lower left corner of the PCB just above the battery connections - I got an 8.75v reading.

I completed the same tests again, but with the battery disconnected and a DC power adapter plugged into the pedal. For each of the above measurements, I received a 9.62v reading.

With the 9v battery connected to the pedal and the DC adapter disconnected, I got a reading of 8.75v for the following measurements:

Both of the + eyelets on the pcb, where the DC adapter connects.
The two visible/exposed/easily accessed tabs on the DC adapter. I couldn't get a reading on the third tab because of the heat shrink.

When testing this, my battery never heated up or got warm after a couple of minutes.

Based on the results in my previous post, my assumption would be that the pedal is getting power. Not sure where to go now. Would it be a short in the circuit, maybe a faulty part, bad soldering, etc...

Yes, your pedal is definitely getting power just fine. The next thing to work through would be THIS, because I see a number of funky looking solder joints. The ideal solder joint is shiny, smooth and conical in shape--and while many of yours are exactly that, there are several that are distinctly funky looking (see marked up photo below for a few of them). I would concentrate on cleaning up those joints first. Go through the entire build and touch up any joints that look at all questionable. Trim down any long wire or component lead ends to the top of the solder joint, and look for solder splash or possible "bridges" between adjacent solder joints (assuming they are not already connected with a trace on the PCB) and clean up those, too. AAMOF, I think I may see a solder bridge between the two LED eyelets (see photo below), which would explain the LED not lighting.

Let us know where you're at after checking all this stuff....

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Awesome! I'll get on that tonight and let you know how it goes. I was having some problems with my soldering gun taking forever to melt the solder, then I learned that this problem can be alleviated by rubbing the solder tip with steel wool before use and periodically cleaning it with a damp cloth.

Hoping you mean soldering iron, not gun, since the latter is a very different thing--good for heavy duty jobs, but definitely NOT for pedal work.

In addition to keeping the tip of your iron clean, you also want to "tin" it periodically, i.e. coat it with a thin film of fresh solder, which really promotes rapid, efficient heat transfer.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Ok,

I am at a complete loss as to what is going on with this pedal. I'm starting to think it's possessed or something.

So here's what I did. I went through each of the solder joints and gave them a re-flow with my soldering iron. I even replaced a wire on the output jack as I suspected that it may be broken. When I connect the pedal back together, I get the LED coming one when it's turned on but not tone effect with the pedal. Essentially, I can turn all the knobs in every direction, including the trimpot, but I get no change in tone. It's as if the pedal is in true bypass when turned on. When I turn the pedal off so that it's in true bypass mode, I get no sound at all.

Any suggestions would be greatly appreciated.

Should I attach new pictures?

Ok,

Some new findings. I'm getting progress but still something is wrong.

I loosened up the pot screws and held the pcb with my fingers so that I could wiggling it around. Turns out what I thought was the pedal turning on wasn't actually happening, as the LED was rather dim. I learned this because the pedal now comes on with a very bright LED, way brighter than before.

So here is what is happening now. I get no sound when the pedal is on, and I get true bypass when the pedal is off. When off, the LED also comes on but very dim.

Do you have a signal tester?

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

No, just a DMM and an audio probe.

Signal tester = audio probe, I think in this case. Start tracing the signal from the input along the audio path until you get no output. That will give us a clue as to where the issue might be.

I know this sounds like a very novice question but whereabouts (very specifically) would I start with the audio probe? Would I start on the pcb. If so, would it be the input eyelet?

Not a noob question at all. I would start at the input jack and follow it into the PCB. It should be easy enough to follow the trace from there.

Great! I'll attempt this on Friday night and post how it goes.

One last question, does it really matter what kind of cap I use on my audio probe?

That was a bit of a confusing process, going through the board with an audio probe. It's hard to follow the trace when you're dong it by following the copper tracks, as opposed to the schematic. I don't know how to read schematics. I also noticed a couple of resistors and one cap where the audio probe would give a signal on one lead but not the other. I'm not sure if that's normal or not. I re-flowed the leads and got the some results.

Anyway, after a couple of hours I gave up. When doing so, I did notice that the wire going from my input jack to the pcb was loose. I think this may have been the problem. I also noticed some cold looking joints. I was using copper wire that I bought 10 years ago. I'm wondering if it has just aged and become more brittle.

My Plan:
I'm going to replace all the wiring and get rid of the cold looking joints. Then I'll put it all back together again and see what happens. The whole process may take me another week because of career and family commitments. I'll post back here with the results once I'm done.

Any insights or suggestions are always appreciated

Part of the process of using the probe is that you get really close to the circuit, detail by detail and you often find issues that you missed before. Do your thing and report back. The fact that you got audio on one side but not the other may need further investigationz.

In regards to those components where I got a signal on one side but not the other, what steps should I take? For example, re-flow, replace the component, remove it and re-solder it on again, etc...

Is it possible for the signal to flow through one side of a component but not the other? I would assume not.

Thanks for your help

I find that the easiest way to trace the signal path through an effect is to use a combination of the schematic and a PCB diagram labeled with the component designations from the schematic. Here they are for the 5-knob compressor:





Even with this info, it's by no means an easy trace, because a compressor--particularly one with 5 controls--is a fairly complicated affair. For one thing, it has both a "dry" and "wet" side (unprocessed & compressed, respectively), as well as a 9-pin IC and 7 transistors to deal with.

It would be very helpful if some compressor-savvy forumite (which leaves me out ) could tell you exactly what points to test for signal. I don't even own a 5-knob comp to be able to try signal testing myself. But I'll see if I can drum up some support for you....

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

If you could report where you get signal (and where you don't get signal) we could certainly point you in a more specific direction.
Tell us which cap or resistor you're probing. And thanks to duhvoodoo you have a nice roadmap.

5-knob signal path. To be followed with a signal tester.

We'll just go over the semi conductor test spots rather than break down every single eyelet along the signal path. When you find the dead spot, then we know which area we need to go through with a fine tooth comb.

Dry signal: IN eyelet > base Q1 > base Q6 > base Q7 > OUT eyelet

Compressed signal: IN eyelet > base Q1 > pin 8 BA6110 > base Q2 > base Q3 > base Q4 > base Q5 > base Q7 > OUT eyelet

_________________
Math illiteracy affects seven out of every five people.

I can't get enough minimalism.

Ok, Good News! It's working.

I cleaned up some of the joints and replaced a couple of wires on the output and input jack, which I think was the main culprit. In hindsight, I should have checked the wiring first, as it would have likely saved me a lot of time. Anyway, live and learn.

I find it to be a rather subtle pedal in that you don't really notice it when it's on in a major way. Not like a phaser or chorus. It's when you turn it off and the compressed tone goes away that you really notice the difference.

Anyway, thanks for everyone's help, much appreciated