Quote:
Originally Posted by DavidU
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Yep, this or similar will do the job without re-winding of motors.
My solution was 555, followed by 4017 (Johnson counter) and resistor ladder network, generating quasi-sinusoidal signal, which was amplified and buffered by PNP-NPN transistor output stage, and no transformer (that's why I re-wound the motor, it was easy job, 200 turns of 0.3mm lacquered wire (if I remember correctly).
It worked fine, frequency was stable enough for visual, and he was able to do photography by guiding (pot mounted in handpad).
These days I have microprocessor solution (for stepper motor) for this kind of problems :-)