Hi everyone.
After a power supply accident (supplied ac instead of dc) at a chain of pedals, i managed to burn the wallwart, but most pedals survived intact.
But the last two in the chain ( a byoc tremolo and a madbeans mutron filter) seemed to have problems. The filter seemed to be burnt (luckilly enough an easy fix -mjust a burnt zener diode) and the tremolo showed a weird behaviour.
When it was powered in a chain it was switching on/off all the other pedals in the chain, regardless of position (the only pedal in the chain that behaved that way). When it was powered on its own, no problem at all.
What the issue would be? Another burnt diode or power capacitor, or something else switch or grounding related?
Thanks in advance
A schematic and pictures of any damage might help.
Sorry about forgetting it.
Here's a link for the schematic
http://byocelectronics.com/schematics/tremolo.jpg
Quote from: tedsorvino1 on August 30, 2023, 09:38:17 PM
When it was powered in a chain it was switching on/off all the other pedals in the chain, regardless of position (the only pedal in the chain that behaved that way).
a. Does, in any instance, on/off switching frequency coincide with tremolo's working rate..??
b. Does D1 LED hights up..??
c. Does D1 LED also serve for effect On-Bypass state..??
Quote from: antonis on August 31, 2023, 06:15:35 AM
Quote from: tedsorvino1 on August 30, 2023, 09:38:17 PM
When it was powered in a chain it was switching on/off all the other pedals in the chain, regardless of position (the only pedal in the chain that behaved that way).
a. Does, in any instance, on/off switching frequency coincide with tremolo's working rate..??
b. Does D1 LED hights up..??
c. Does D1 LED also serve for effect On-Bypass state..??
A. I'm not sure
B. Yes
C. Yes
I repeat the pedal was working perfectly well before the accident and the positive answer on questions B. and C. is part of perfect functioning. The switching problem happened just after the accident. And I seriously doubt that it has to do with anything else than the power supply part of the circuit (since when it's on it works perfectly well, and when it's off the signal passes through it perfectly fine and noise free).
Could it be that the pedals all boot up in an off state, and that switching the Tremolo on causes a short which briefly drops the power to zero and "reboots" all the pedals?
This assumes that you haven't got any true bypass pedals. How the hell switching a tremolo on could turn those off I can't imagine. Some sort of demonic possesion of your pedal would be required. :icon_twisted:
So...I'm assuming we're talking about FET-switched pedals. You could test this theory by taking the Tremolo out of the chain, and turning the power supply off and on again. What state are the pedals in? Is it the same as the state they finish up in when the teemolo affects them?
(I'm hoping for "Yes" and "Yes", clearly...)
I'd check/replace D2 & C9..
(https://i.imgur.com/nUTkxRj.jpg)
P.S.
D2 is the "cause" for wall-wart burn..
(it appeared like a short across supply during half-wave cycle..)
Quote from: ElectricDruid on August 31, 2023, 09:13:25 AM
Could it be that the pedals all boot up in an off state, and that switching the Tremolo on causes a short which briefly drops the power to zero and "reboots" all the pedals?
This assumes that you haven't got any true bypass pedals. How the hell switching a tremolo on could turn those off I can't imagine. Some sort of demonic possesion of your pedal would be required. :icon_twisted:
So...I'm assuming we're talking about FET-switched pedals. You could test this theory by taking the Tremolo out of the chain, and turning the power supply off and on again. What state are the pedals in? Is it the same as the state they finish up in when the teemolo affects them?
(I'm hoping for "Yes" and "Yes", clearly...)
Needless to do it since i've built all pedals andbthry are abdolutelly true bypass.
Antonis answered my question and it is what i sudpect.
Quote from: antonis on August 31, 2023, 09:39:56 AM
I'd check/replace D2 & C9..
(https://i.imgur.com/nUTkxRj.jpg)
P.S.
D2 is the "cause" for wall-wart burn..
(it appeared like a short across supply during half-wave cycle..)
Thanks man for the info on D2. I was suspecting those 2 parts.
Na 'sai kala
Quote from: tedsorvino1 on August 31, 2023, 10:51:43 AM
Quote from: ElectricDruid on August 31, 2023, 09:13:25 AM
Could it be that the pedals all boot up in an off state, and that switching the Tremolo on causes a short which briefly drops the power to zero and "reboots" all the pedals?
This assumes that you haven't got any true bypass pedals. How the hell switching a tremolo on could turn those off I can't imagine. Some sort of demonic possesion of your pedal would be required. :icon_twisted:
So...I'm assuming we're talking about FET-switched pedals. You could test this theory by taking the Tremolo out of the chain, and turning the power supply off and on again. What state are the pedals in? Is it the same as the state they finish up in when the teemolo affects them?
(I'm hoping for "Yes" and "Yes", clearly...)
Needless to do it since i've built all pedals andbthry are abdolutelly true bypass.
Antonis answered my question and it is what i sudpect.
Ok. In that case they're only being "turned off" in the sense that they're being deprived of power. They're not actually changing from "Effect" to "Bypass", which is what I thought you meant initially. I agree with Antonis that a short from either that cap or diode is most likely, and I'd certainly fix those two and then see what things look like.