# Duo phase slightly "off"



## Ozzytown (Apr 17, 2019)

I've got one side of my duo phase that's slightly "off". The led should flash like a pulse. Fading down before going back on again. Very smooth, like. 
   But one side flashes more harshly. Almost like a blink. So it sounds a little choppier. What possibly controls the led that makes it quickly fade off before going on again?
   I also noticed that side seems brighter as well. Its definitely not the transistor, as I changed that out. And adjusting the trimmers doesn't give it that smooth pulse.


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## zgrav (Apr 17, 2019)

good job getting this build together with both sides working.  you should be able to adjust the trim pots on the board to change the character and "choppiness" of the flashing.  I suggest leaving the side alone that you like already, and experiment with the two adjustments for the other one.  one should adjust where the light turns on/off, and the other should adjust how much past that point the light goes in the cycle.    experiment a bit and see how each control affects the sound.  you should do that in a dimly lighted area since the light in the room also affects the sound.


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## Ozzytown (Apr 18, 2019)

I've built about 8 of these. And this one is particularly different. I've tried adjusting the trimmers to no avail.
    The way it should correctly flash is to dim off and then on again. The bad side is more of a quick on/off. Its weird.
     I thought maybe it's the led itself. But its not.
      Another thing I noticed is that the bad side is brighter. I'm wondering if I screwed up in a resistor somewhere? But I'm colorblind and I just cant tell? I tried looking at the schematics by the led/trimmers, but that's way over my head what's going on there!


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## Robert (Apr 18, 2019)

Can you post a couple pics of the side that is giving you trouble?    I'll see if I can see any values that might be off.


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## zgrav (Apr 18, 2019)

Try reflowing the connections on the resistors and caps in the LFO circuit.


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## Ozzytown (Apr 18, 2019)

Robert said:


> Can you post a couple pics of the side that is giving you trouble?    I'll see if I can see any values that might be off.


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## Ozzytown (Apr 18, 2019)

Its totally gotta be some value off. I built 2 of these simultaneously and they both are acting the exact same way. Same side too. The led is significantly brighter. I'm not sure which resistor controls that?


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## Dice1012 (Apr 18, 2019)

Power supply? I built a combo pedal with 5 effects in one enclosure. had some problems wirh the effects sounding "off" and finally figured out it was the Boss power supply I was using.


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## Robert (Apr 18, 2019)

Still looking, but this resistor is the wrong value.

Should be 3K9, that appears to be 39K.


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## music6000 (Apr 18, 2019)

Robert said:


> Still looking, but this resistor is the wrong value.
> 
> Should be 3K9, that appears to be 39K.
> 
> ATTACH=full]379[/ATTACH]


Yep,  It's Orange, White, Black, Red, Brown = 39k
Should be Orange, White, Black, Brown, Brown = 3k9
R2B appears to be 39k, should be 3k9
Check this value on the other Half of PCB.

Easily done with a humongous Board like this!


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## Ozzytown (Apr 18, 2019)

Robert said:


> Still looking, but this resistor is the wrong value.
> 
> Should be 3K9, that appears to be 39K.
> 
> View attachment 379


Hey!hey! Beautiful!
   That was totally it! You saved me two projects! Thank you so much!


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