Hello Folks, a friend gave me a 4x5 Dual Dichro head, and I want to sell it
on e-bay, as I don't do any color work.  I thought I should check it before
I sold it, so I plugged it in and started fooling around with it.  I think I
found a problem, but I'm not sure what to make of it, so I am seeking the
wisdom of the net.

I plugged both power cords into the wall, so the head was both on and
enabled for exposure.  I had the unit on its side, so I could adjust the
knobs and watch the light output.  I started to turn all three knobs,
yellow, magenta, and cyan, and I could see the color of the light changing.
When I turned the yellow and cyan knobs, the output numbers changed
accordingly: low numbers starting out, higher numbers as I turn the knob
clockwise.  But I couldn't see the magenta number changing; the light output
changed, but not the number value.  When I changed the yellow and cyan
lights, I could see small changes in the magenta number.

Any idea what might cause this?  And how I can fix it?  It's probably
essential that the number reflect the actual value of the output.

Any help would be appreciated.

Cheers,

-- Mark