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Vintage threads from the first ten years

Morley Volume Wah

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12/8/1999 6:50 AM
Mike O	Morley Volume Wah Where can you get a schematic for one of these? I purchased this one in the late 70's. It's all chrome and plugs into a 110 outlet.It seems to be alittle noisey and when it's on by-pass it seems to rob a little volume.Is there supposed to be a shroud over the photo cells? Any help wpild be appreciated. Mike O

12/8/1999 10:28 AM
GFR	Try the Morley website.

12/8/1999 1:33 PM

Yes, there is a shroud over the photocells. The noise could be generated by a few things. One, resolder cold solder connections and check the Electrolytic caps inside. Also, I have had to replace trim pots on a few Morley pedals like yours. Mark a spot on the PCB where the wiper of the trimpot lies and turn the trim pots to loosen them upand clean the wiper off. If this does not help the noise, replace the pot.

CJ

12/9/1999 7:50 PM

I usta have one of these, there was a
black cardboard shroud, kinda wedge-shaped,
taped over the photocells. The flap that
moves when you move the pedal lays flat
against the open side of the wedge when
it is in the 'closed' position.

I traced out the circuit at one time, doubt
I still have it, but as i recall the volume
pedal circuit was very simple, a resistor
which gets loaded to ground by the photocell.
So there is always some attenuation, and any light
leaking in will make it worse.

I had some noise problems which were improved
by changing the grounding a little (I think one
of the jacks relied on contact to the chassis
for its ground) and adding another filter cap to
the power supply.

I also added a level control to the wha circuit,
because it boosts the signal a lot, which isn't
always convenient!

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