Model number could help. Then I could determine year of production.
Any electronic device can suffer from oxidation of the switches on the low voltage low energy signals. Spraying out with contact cleaner can help, else pulling a piece of paper through the contacts. Use no sand shedding paper, aluminum oxide is a permanent insulator. Warning contact cleaner is flammable, no smoking, open flame, pilot lights, or electricity turned on or off within 10 m.
My Hammond used a motor driven drum to produce vibrato, but I don't know when that patent expired. In the fifties many organs produced tremelo, a variation of volume, instead of vibrato, a variation of pitch.
That diode at the lower right could be some sort of a relaxation oscillator, a sawtooth generator affecting volume.
See Organs and organ music for church, home and theater. A reference source by Colin Pykett for articles on various aspects of organ technology.
Any electronic device can suffer from oxidation of the switches on the low voltage low energy signals. Spraying out with contact cleaner can help, else pulling a piece of paper through the contacts. Use no sand shedding paper, aluminum oxide is a permanent insulator. Warning contact cleaner is flammable, no smoking, open flame, pilot lights, or electricity turned on or off within 10 m.
My Hammond used a motor driven drum to produce vibrato, but I don't know when that patent expired. In the fifties many organs produced tremelo, a variation of volume, instead of vibrato, a variation of pitch.
That diode at the lower right could be some sort of a relaxation oscillator, a sawtooth generator affecting volume.
See Organs and organ music for church, home and theater. A reference source by Colin Pykett for articles on various aspects of organ technology.
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Model is G-1,circa 1955.no longer in organ,I built it into a head for guitar,but vibrato is kind of in limbo.
1955, would be tremelo only.
Yeah. OA2 is a tube that shorts at a certain voltage, like a zener diode.
They are not very reliable, so changing to a zener diode may make the circuit work.
That voltage from the big cap to the plate of the diode should ramp up linearly until it shorts. Then the gain of the above tube should be varied by that voltage. That makes the tremelo. On-off from switches on the right.
Yeah. OA2 is a tube that shorts at a certain voltage, like a zener diode.
They are not very reliable, so changing to a zener diode may make the circuit work.
That voltage from the big cap to the plate of the diode should ramp up linearly until it shorts. Then the gain of the above tube should be varied by that voltage. That makes the tremelo. On-off from switches on the right.
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