I have been tweaking my pp and have a sort of prob. I fitted a 10turn 100R sense pot and agjusted the other values accordingly. This gives me great control - almost 3" for a 5c coin. Prob is temp. I think that it is the transistor driving the led. As it warms up its Vbe changes and I have to re-adjust the sense pot. A scope on the base shows no drift in the 'integrated' pulses. I am thinking of fitting a comparator instead.All thoughts very welcome.
(Circuit in my other pp posts)
(Circuit in my other pp posts)
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