Build Your Own Clone Message Board

https://buildyourownclone.com/collectio ... gnaltester

Very useful diagnostic tool for pinpointing where in the circuit the problem is occurring.

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

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

A signal tester is an extremely simple device. All you need to make one is an old instrument cable (that one we all have that went bad at one end is PERFECT for this), an alligator clip, a couple of lengths of wire, and a 100n (0.1uf) or larger value capacitor. Refer to the signal tester instructions at the link below for the construction details.

http://byocelectronics.com/signaltesterinstructions.pdf

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

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

that seems easy enough. awesome. thanks for the info!

I think I happened to have found everything I need to make an audio probe/signal tester in my random stash boxes! before I continue, does it look like I have everything I need?

Looks good from here. Just solder things together and you should be ready to go.

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

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

ok I think I got it. I'll follow the steps you posted on samber_dino's post.

https://r.tapatalk.com/shareLink/topic? ... source=app

I followed these steps:

1. Middle leg (base) of Q1 (clean input signal, unity volume)
2. Lug 3 (left) of VR1/Sensitivity pot (clean input signal, unity volume)
3. Pin 3 of op amp (clean input signal, unity volume)
4. Pin 6 of op amp (LOUD, distorted signal)
5. Lower leg (collector) of Q5 (LOUD, distorted signal)
6. Lower leg (collector) of Q6 (LOUD, distorted signal)
7. Lug 3 (left) of VR2/Attack pot (LOUD, distorted signal)
8. Middle leg (base) of Q3 ("wet" signal with audible swell, unity volume)
9. Lug 7 of footswitch ("wet" signal with audible swell, unity volume)

Mine failed at step 3. I get a signal but it is weak.

I tested C9 and R16 and R15. they are all the correct values.

I replaced C8. it didn't help anything. so far, I've replaced C9 and C8.

I am not well versed in this circuit, so it's possible one of the other mods will give you more specific direction, but in my experience with using a signal tester, resoldering the problem joint is highly likely to solve the problem—or at least move it down the list to a later test point. In this case, you are working with the op amp, so one thing you could try while waiting for other help is to carefully remove the IC from its socket, reflow the solder on the 8 pins, and then gently replace the chip.

Again, this is in the category of "couldn't hurt, and might help", not "definitely will fix your problem". I know I get anxious to keep moving when troubleshooting a pedal, so I offer it in the spirit of keeping you going.

_________________
Scott

My band, Austin Hollow

Test the signal at lug 2 of VR1. With the knob full turn CW (clockwise), it should sound the same as the signal at lug 3. Then you should be able to reduce the volume of the signal by turning the knob CCW.

_________________
*patience is a virtue*

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

I am able to reproduce that. and furthermore when I measure pin 3 on the op amp when the sensitivity knob is all the way up, I get unity signal.

OK, with that adjustment, where does the signal tester now show the first problem?

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

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

The Sensitivity knob is literally a volume knob that controls the signal level going into pin 3 of the op amp. So keep that in mind when tracing out the envelope trigger signal. If you have that knob full turn counter clockwise, it's going to kill the signal.

_________________
*patience is a virtue*

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

so then I should proceed with both knobs turned fully clockwise? trim pot about half way?

Yes.

_________________
*patience is a virtue*

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

1.Middle leg (base) of Q1 (clean input signal, unity volume)
2.Lug 3 (left) of VR1/Sensitivity pot (clean input signal, unity volume)
3.Pin 3 of op amp (clean input signal, unity volume)
4.Pin 6 of op amp (LOUD, distorted signal)
5.Lower leg (collector) of Q5 (LOUD, distorted signal)
6.Lower leg (collector) of Q6 (LOUD, distorted signal)
7.Lug 3 (left) of VR2/Attack pot (LOUD, distorted signal)
8.Middle leg (base) of Q3 ("wet" signal with audible swell, unity volume)
9.Lug 7 of footswitch ("wet" signal with audible swell, unity volume)

fails at 5, 6, 7. I didn't test further than that. the sound is the same at all three points and kind of hard to describe. If I hit all the strings on my guitar really hard, the signal is scratchy/staticy and very weak. If I hit one string softly, it is louder and then kind of sputters away.

Can you get DC voltage readings on the three legs of Q4, and on the collectors (lower legs) of Q5 & Q6?

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

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

Q4
2.75 emitter
3.1 base
6.7 collector

Q5
2.5 collector

Q6
2.5 collector

OK, Q4 looks pretty good but the Q5/6 collector voltages are very low. Please measure voltage at the following three places: Lugs 2 and 3 (left and middle) of the Attack pot and the left leg of the Zener diode, D1.

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

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

lugs 2 and 3 of the attack knob are basically the same around 2.8 V
left side of D1 is 5.4 V

btw my power supply is giving me 9.46 V

OK, you're losing voltage between the Zener and the Attack pot--both of those pot lugs should be at that same 5.4V value. Sounds like there's a partial short somewhere in between. I'd start by carefully inspecting in the area around R6-R7-R8-R10 on both sides of the PC. Look for possible solder bridges or wire strands between eyelets not already connected with a board trace. Clean up anything like that that you find. Gently scrape off any degraded solder mask or other crud with the edge of a small flat-bladed screwdriver.

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

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

what are these joints supposed to look like? I've been trying to separate the solder joints but can't.

Not a problem--those two eyelets (D3 & R23) are connected with a trace.

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

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

I just figured out why I'm getting low voltages at the attack knob. Those capacitors that I replaced (C8 and as C9) are attached to the board by pieces of wire. Hopefully you can see in the pictures. I noticed while working on it that the closer my hands were to the capacitors, the lower the voltage was at the attack knob. If I back my hands all the way from the capacitors, the voltage goes up to about 5.4 V. I destroyed both of the original capacitors that came with the kit getting them off the board so I can't replace them with what byoc sent. Diagnosing the problems are gonna be hard if I can't get my hands near the board. I'm not sure how to proceed from here. Other than replace the capacitors with the right size to fit on the board. Can byoc tell me what I need to get to replace the part that was included in the kit?