In article , Scott Miller wrote: [...]
Yes, a bit. At higher temperatures, the recovery time usually gets a bit longer and the corners in the curve get a bit rounder.
1N4007 is about the worst one on the market. You want a diode that is "fast recovery" or "high speed"Remember it is the ESR of the capacitors not their capacitance that matters most to what the diode capacitance is doing. The storage effect has most of the longer term effect. The capacitance increases the sharpness of the output edges that happen when the transformer's voltage swings up and down.
Yes, there are better ways. If you are regulating the voltage by means of a servo loop that controls the duty cycle, you don't need to adjust the frequency for the highest voltage. I'd be inclined to adjust for the lowest supply current to maximize the battery life.
I can offer but little help there. I don't use PICs. The basic thing to check is what happens to the current cycle's pulse width if it ends just as you are updating the registers.
I don't know that this matters in your case. The gain of the tube is very voltage dependant. You are only counting pulse not measuring how big they are so a slight gain shift shouldn't matter. I think you can safely leave the detection on the cathode end.