Univibe issue - bulb not bright / deep enough flashing.

nznat

Member
Im having trouble with a vibe build. Here's the thing. When i plug in the power supply, i see the bulb go brighter and deeper in the flashing mode, seems perfect, yet after about 1 second after i plug in the power supply it suddenly goes more dim, the depth of the flashing has gone much dimmer / less, thus the lush univibe tone is mostly gone because of this, doesn't sound correct anymore. Any ideas on power supply issues on the pcb or what part of the univibe circuit controls the power of the bulb itself? Can anyone point to these areas and caps etc that regulate the bulbs depth of flashing on the schematic attached so i can remedy this situation?
much appreciate your help
 
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Im having trouble with a vibe build. Here's the thing. When i plug in the power supply, i see the bulb go brighter and deeper in the flashing mode, seems perfect, yet after about 1 second after i plug in the power supply it suddenly goes more dim, the depth of the flashing has gone much dimmer / less, thus the lush univibe tone is mostly gone because of this, doesn't sound correct anymore. Any ideas on power supply issues on the pcb or what part of the univibe circuit controls the power of the bulb itself? Can anyone point to these areas and caps etc that regulate the bulbs depth of flashing on the schematic attached so i can remedy this situation?
much appreciate your help

Post pictures, top and bottom, of your
Board.

Which board is it? Have you double and triple checked all the component values and your solder joints?
 
i have made three of the boards, all came out the same, soldering is fine. everything now working fine except bulb depth of flashing. just not deep and bright enough. Or thats what i think. the sound is more like a tremelo effect rather than a swealing lush vibe effect
 
i have made three of the boards, all came out the same, soldering is fine. everything now working fine except bulb depth of flashing. just not deep and bright enough. Or thats what i think. the sound is more like a tremelo effect rather than a swealing lush vibe effect
This is standard practice, saves the guessing game:
 
above picture of schematic? board wont show much as you cannot see the tracks

We only have your word as to the quality of your soldering, general assembly, etc.

It helps to give us pictures so we can reference the schematic and try to point you in the right direction?

Right now we only know your bulb is acting erratically.

If we can view your board, determine what the LFO looks like as well as the lamp driver, we can gives you some paths for troubleshooting.

If you don’t, we are flying blind.
 
Just attached my entire schematic. I dont need to send picture of board aswell as the soldering is the best of the best as its a SMD / Surface mount i got made at the factory, the soldering is perfect. The thing with the pedal is that it is working, all functions, but the vibe effect sounds like shit. more so like a bad tremelo, and i almost get there with the mini pot adjustment but it just doesn't get the deep and "swishy" sound. its flat and tremelo. Ignore the parts that are relay switching, as the pedal has two sets of pots to have dual settings.
 
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I don’t see a schematic here. Maybe I missed it. I know the time I had a similar issue with a vibe sounding like a tremolo my Ldr had too large of a spread. And the dark resistance was too high. I solved this by running a resistor in parallel.
 
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