Build Your Own Clone Message Board

You should get continuity to ground on the bottom of R18 because it's supposed to be connected to ground. However, you do not want continuity to ground on the top. That would imply a short to ground.

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*patience is a virtue*

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

No continuity on the top, so that's good at least!

Well, C6 was tough (for me) to remove with the way the lead was clipped/bent. I managed to get it out but ruined the capacitor. I have another.
I noticed on the top of C6 the eyelet is half gone. I can't be sure if it's from my desoldering or if it was that way before. Is there a jumper connection I can make like we did for the last time?

As long as the damage is only on the top (component) side of the PCB, you should be OK. The trace connections for both ends of that cap are on the bottom of the board.

Photos are always helpful to us in assessing the situation and making recommendations (hint, hint).

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

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

Sorry I should have been more specific. On the bottom side of the PCB (solder side) the eyelet is half gone. So I think indeed it's damaged. I'll get a photo.

Does that eyelet seem fixable? I'm wondering if it's time to bite the bullet and start over with a new kit now that I have half an idea what I'm doing.

Wrong question. The important thing to ask is "Can I still make the connection between that capacitor lead and the next component that it should connect to?" The answer to which is "Sure, no problem!"

That eyelet connects to the top of R18 with a trace on the PCB which appears to be gone, probably ripped off along with half of that solder pad. No matter. Since you're installing a new cap there, this is a very easy fix. Push the cap lead through the half-gone eyelet and solder it to what's left of the eyelet, BUT DON'T TRIM THAT LEAD. Instead, bend it over and tack-solder it to the top solder joint of R18, and then trim off any extra lead that protrudes past that joint. See marked up image below.

At this point, you should have continuity between that cap lead and lug 7 of the footswitch. Confirm this with your multimeter. If it checks out, reassemble the pedal and test it out.


Nah, you're a long way from that! We got this!

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

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

Many thanks. That went smoothly and I have continuity between the cap and lug 7 of the footswitch. However, I still get very low volume and when I do a signal test it still doesn't get the wah effect past C6. Note, the volume when I test R14, the wah is light, but the overall volume is the same as when I test C6 (just without the slight wah). What might be next to test?

Now that you have the various PCB connections sorted out, can we get a new set of pin voltages for the large IC? I'd like to see voltages both with the IC installed and with it removed. For those pins that don't give a stable readout and just drift down in the mV range, don't bother to report those--just show a dash for such results.

Please report the results in a single column--the forum won't display side-by-side columns correctly.

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

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

One other thing--since the responsiveness of this circuit various widely with the various control settings, I just fiddled around with mine with my CV Tele Custom. For the strongest auto-wah output, I found the following settings to work:

Range: Mid-point (noon)
Attack: ~1/4 (9 - 10 o'clock)
Sensitivity: ~3/4 (3 o'clock)

Of course, the toggle switch should be set to the envelope side.

You may just want to try running at those settings and see if the output improves.

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

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

IC Installed:

1 - 0.65v
2 - 0
3 - 3.64 v
4 - 2.69 v
5 - 0
6 - 0
7 - 0
8 - 1.48v
9 - 1.34v
10 - 0
11 - 8.35v
12 - 0
13 - 3.03v
14 - 3.03v
15 - 0
16 - 0.65v

IC Removed:

1 - 0.65v
2 - 0
3 - 3.75 v
4 - 2.69 v
5 - 0
6 - 0
7 - 0
8 - 1.47 v
9 - 1.34v
10 - 0
11 - 8.35v
12 - 0
13 - 2.7v
14 - 2.7v
15 - 0
16 - 0.65v

Unfortunately I think I've sloppily removed this IC one too many times. The tips of pins 8 and 9 came off. I suppose I could solder a lead there? One step forward and one step back

I would just go ahead and replace the 13600D (which is a dual operational transconductance amplifier (aka dual OTA). They're not expensive--the shipping will run you more than the part. You can get it here: https://www.digikey.com/products/en?WT. ... =NJM13600D

Your numbers look pretty good except for pins 8 & 9 with the IC installed. I get just about 5.0V on mine on those two pins.

The V571 is a compander (compressor/expander) chip--not the same thing.

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

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

Thanks, will do. What are common causes for the voltage differences? Is there a possibility the op amp was the problem? I'm guessing it's probably something on my end, but who knows.

That's a good question. Might be the OTA chip, might be something you did that we haven't found yet, or might be something beyond my meager knowledge of how an envelope filter works! I'll see if Keith might comment on your question....

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

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

OK, thanks. I'll post back at the end of the week once I receive the new op amp.

Hello again! I got the replacement op amp and still have issues. I think at this point I will take all these mistakes and learn from them and get a new kit. The way it is now, if the toggle switch is set to Manual, I get wah and the manual knob controls it. The volume is about 1/3 of what it is in bypass, however. I'm guessing that is not right? And when envelope mode it can go from no sound at all to a very faint sound and the other 3 knobs don't seem to do much. I have a hunch the C250k sensitivity may not be quite right since i had to replace the leads on that. Is there an easy way to test that a pot is properly working in the circuit?

One other general question - when you use the helping hands, do you normally put some cloth or something to protect the PCB? I can see I have some light scratches that are on the traces on the board. I'm wondering if that might be the problem too.

It's a mess, but at least I have learned and I hope the next one will go well!

Thank you!

I was exchanging emails with Keith about your problems with this pedal, and we came back to that high pin 7 voltage that you reported on the smaller op amp, the 4458. That suggests that this IC may not be functioning correctly. Could you please recheck the signal strength on pin 1 of that IC? You said before that the signal there was "low". We need to understand that more quantitatively. The first half of that op amp is what's known as a "unity gain buffer"--that is, it buffers the incoming signal but doesn't amplify it. So the signal volume on the output of that half of the op amp at pin 1 should be the same as the incoming guitar signal. So use your signal tester on the tip of the input jack to hear the incoming signal volume and then test at pin 1 of the 4558 to hear how that compares. Let us know what you find.

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

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

Hi, the volume on the tip and pin 1 is the same, so I guess that is as expected.

Also, my results are a bit different than before. Previously I lost the "wah" effect on R18. I now have the Wah effect on R18 and Eyelet 7, but the volume is very low still. If I do a signal test on pin 10 of the larger IC, I get a louder wah signal. Is there perhaps some way to trace it as to where the volume drops off?

A little update. I reflowed D2 since it looked like it might not have been totally right (also reflowed other stuff when in there). Not sure if it is why, but I now get a more consistent wah on the envelope mode and the pots seem to be working. The main issue is that the volume is low. Like 1/3 of the bypass volume.
How is the volume on your pedal when engaged vs in bypass. Maybe it's just the nature of this pedal?

That's definitely not normal. Mine maintains the same volume as bypass, assuming that the controls are dialed in properly. Try setting your Range and Sensitivity pots at ~ 3 o'clock (where 12 o'clock = mid-point) and the Attack pot to about 9 o'clock. See how that sounds, then twiddle the Attack pot in both directions to see where you get the strongest response.

BTW, do you happen to have another 4558 or other dual op amp (TL072, TL082, NE5532, OPA2134, etc.) in a socket in another pedal? If so, try swapping it for the 4558 in this pedal and see if it helps.

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

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

Thanks, I did have a spare and tried it but no difference.

Also I got some replacement pots for the sensitivity and attack ones that were compromised. When going to replace them, I noticed the eyelet is not in great condition. Attached is a picture of the front and back. I pointed to the the ones I think are problematic. For the ones on the back, can you confirm where I should make a manual connection? The one on the front I think may be OK, it just seems to have a tiny piece of the eyelet maybe missing.

In your experience, when volume is low, what are common causes? Also just curious, if I used the wrong resistance (not that I think I did) would that typically mean the effect doesn't work at all? Or are there too many variables to answer that?

Thank you.

You can check continuity using your DMM. You can see the traces, so if there’s no continuity, you can use jumpers the connect the eyelets to whatever is next In the circuit.


Sent from my iPhone using Tapatalk

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Pedal building is like the opposite of sex. All the fun stuff happens before you get in the box.

^ This. None of those look too bad to me. You definitely need to work on your de-soldering technique, though--you're consistently causing eyelet damage when you remove things.

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

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

I replaced the pots and I think I'm making some progress here. While the volume isn't the same as bypass, it's reasonable I think. The only issue I think I'm having is that the wah effect sounds a bit crunchy. Like a dirty pot almost. Here's a sound clip:

https://clyp.it/15js3rky?token=b4e1698c ... 5e371ddeb1

I strum once in bypass, then once in envelope mode. Any suggestions on what might cause that sound defect?