Re: Bell and Howell TQII 1652 16mm projector
Hi!
The 28V max needed for an LM2917–8 can be provided by an LM317T adjustable regulator or a 7824 with a 3.9V zener in parallel with a 10u 25V electrolytic in its middle ("GND") lead, or, if you can find space in your Projector, a small "LM317 Adjustable PSU Module", which you can buy cheaply online from Chinese supply sources, either ready–built or as a kit of parts with a bare pcb!
A darlington transistor such as the TIP147 or BDX53 should do for the LM2917–8 circuit example suggested in the previous post!
I wouldn't be at all surprised to find B & H have buried a '2917 in that module to begin with – it is, after all a similar speed control arrangement with simple switched potential dividers adjusted for each film speed!
Chris Williams
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It's an enigma, that's what it is! This thing's not fixed because it doesn't want to be fixed!
Last edited by Chris55000; 30th May 2019 at 5:55 am.
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