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Old 26th May 2019, 6:25 pm   #22
af024
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Join Date: Jan 2003
Location: Ashby-de-la-Zouch (it's not by the sea)
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Default Re: Bell and Howell TQII 1652 16mm projector

Taking a look at various LM2901 and LM2917 datasheets, I came across this circuit. Perhaps this would form a suitable building block? Of course there are still some challenges as the project supplies an unregulated nominal 40Vd.c. and this IC is limited to 28Vd.c. I think.

I'm not sure what current the motor will pull on full load.

I don't know whether I need a PWM solution to keep the torque up.

My aim would be to try and create something that would just drop in as a substitute, so I have 7 pins (and existing signals, presets etc) to deal with.

Not sure what to do for R1, C1 and C2.
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Now where on earth did I remove that from?
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