Build Your Own Clone Message Board

1 MEG REVERSE AUDIO POT[/quote]
Awesome thanks

Ok I tried to cleans this up a little today
I took the belton unit off for a third time and tooks some pics to show to some fresh eyes in case i'm missing something
wish I knew how to work a camera

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Doh! Stupid Diode

Your build is pretty clean and I can't spot anything out of the ordinary. Play through it without the brick in. That will give you just dry signal and you can check to make sure there is no funkiness going on there.

Beyond that, I recommending axing the trim pot beneath the pcb to return the circuit to stock. I know you had it stock before and still had issues, but who knows... Then if you get it working, you can always just tack a 10k resistor on top of R14 to knock the reverb back down.

I absolutely hate suggesting new parts, because that is almost never the problem, but if you get the same problems after getting back to stock you might think about ordering another brick. Before you do that though, make sure and probe the wet signal path like I suggested earlier. You can actually do that up to the brick input when the brick is not installed. This might tell us if something is suspect in the signal path between the input buffer and the brick.

Your voltages look good and that second sound clip sounds a little harsher than usual, but not too off. That sort-of slap back effect at the end of the reverb decay is part of the brick emulating a spring reverb. Yours seems to sound harsher than others though.

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MasterDelayer/Reverbrador/Ampaholic/TopJacker

Ok I get signal all the way thru as follows

R6 loud signal > R9 volume drop> R10 > IC1 PIN6 > IC1 PIN 7 loud signal > C5 BRICK PIN 4 > BRICK PIN1 volume drop> R11 > R12 signal tone throbbing > IC2 PIN6 > IC2 PIN 7 loud signal > TONE POT LUG 2 > C13 > REVERB LUG 2 volume drop > R19 > C14 > Q1 > C15 > R22 loud signal

there was a small volume drop and a weird throbing like a slow tremolo effect on the far side on r12 until ic2 pin 7 where the volume returned and the throbbing stopped
I'm using function generator set on a straight sine wave for the test tone
The volume drops are maybe 1 or 2 db's
So what does this tell us?

Edit:
I was just looking at the schematics trying to follow this signal path ( maybe I'm a learn sumpin )
And noticed the ic's are labeled 4558 on the schematic and TL072 on the parts list
I have TL072cn ic's installed, Do I have the right ones installed?

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Doh! Stupid Diode

I'm not sure what's going on with the signal throbbing at R12 (that's within a feedback loop in the reverb recovery stage and sometimes weird stuff can go in those), but I don't have a build here to determine whether that's normal or not. I'm mostly concerned with your reverb signal. Does the reverb signal sound like it should at IC2 pin 7 or at the middle lug of the reverb pot? Or does it sound like there is something wrong with it?

As far as the dwell circuit, it takes the signal from IC2 pin 7 and feeds it back to the reverb input. So if you have a good strong signal at IC2 pin 7, that part of the circuit is good. You should have basically the same signal on one side of R15 when the dwell knob is cranked. R15 will then knock that signal down a bit before feeding it back to R9. The dwell knob knocks it down more from there. So the dwell circuit feedback loop basically feeds the reverb output back to the input for more resonance, depending on where the dwell knob is set. With R14 at stock, it should be a fairly obvious effect.


BYOC probably just changed op amps at one point. They work the same; TL072 is generally regarded as a better op amp for these types of applications.

Did you get rid of that trimmer underneath the pcb and return R14 to stock?

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MasterDelayer/Reverbrador/Ampaholic/TopJacker

I haven't taken it off yet
I ordered a new belton unit and I'm waiting for it to show up
I'll let you know how it goes

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Doh! Stupid Diode

Got the new Belton unit installed today and It's WAY better
must be something faulty in the old one
I't very nice reverb.finally get to hear what your all talking about
still not much control on the dwell knob but it's a least very usable
Thanks for all the help

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Doh! Stupid Diode

Oh good! Glad to hear it!

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MasterDelayer/Reverbrador/Ampaholic/TopJacker

Hi All,

I ran into the same problem a long time ago and I needed a reverb pedal because I just bought an amp w/o reverb. Dwell didn't seem to work, the pedal sounded good w/o it, so I put it on the board all is well. Along comes COVID and I have time so I pulled it off the board and followed the info from Morgan and Duhvoodooman. Everything seemed to check out ok, pot, voltages etc. When I jumped R15 I finally got some sonic reaction from the dwell knob. (Oscillation mostly), I put in a 100K resistor instead of the 180K for R15, back to nothing. Then I put a pot in for R15 as suggested. The dwell seems to work pretty good with R15 somewhere between 30-60K. I left the pot in to see how things sounds in a band setting and revisit it later. I was almost ready to get a new module.....

Thanks guys!! I'm glad this info is archived so I could just review the debugging tips that were already provided. I bought that pedal when it first came out. The schematic says 9/2009 and on 11/11/2020 it is completely working. It been on my board since I built it and hurray Dwell works now!!!

Thanks again!! Thanks to all our Veterans!
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