Flatline Help Needed....

[Barcode80]

So I have built two flatline compressors. I built one from the PCB layout in MarkM's gallery, and one from Ulysses' vero. Both have the same issue. Neither are actually compressing. I used a homemade photocoupler from an LED and an LDR in both. On both of them, when nothing was happening, i cut open the shrink on the photocoupler and realized that the LED was just on and staying solid. any ideas?

[David]

R.G.'s PCB layout is proven.  Just make sure the traces for the bias part in the circuit have continuity.  There was some defect in the PCB I made for it about 4 years ago and I couldn't get bias voltage.  I wound up creating a daughterboard with a 386 bias circuit, but never completed the pedal.

[oldschoolanalog]

Have you tried different LEDs & LDRs?
I built one of these using R.G.'s layout an it works beautifully. John Lyons etched me a real nice board (shameless plug )
I used a VTL5C3. My favorite guitar comp to date.
Dave

[Barcode80]

Hmm, I'll try R.G.'s layout then. I'll report back with results!