Moderators: Dave Moll, Andrew Davie, Steve Anderson
Steve Anderson wrote:Hmmm, it's always a good idea to ask yourself, "Why did it fail? It was fine at the start." In builds like these it can be so many things...did a high voltage get into the FET from somewhere? Solder splashes, bad joints, an off-cut of wire floating around?...all the usual suspects. It's great when you find the culprit, when you don't it's an uneasy feeling.
Steve A.
Klaas Robers wrote:It is more likely that the software ferequency of your computer has a slight deviation. That is the reason that sync pulses are needed to keep the (big) picture stable.
But if you want to have an idea about the precision, time yourself how long it takes until the black bar is back in the same position. If that is 100 seconds (I gues that it is much more) then it is 40 000 pulses of the 400 Hz signal. One pulse less or more on the 40 000 pulses. So the deviation of the frequency 1 / 40 000, or 2.5 10^-5, which is reasonable for a crystal oscillator.
There is no reason to adjust this for your aplication in a camera. Besides that, if you do so, you adjust it to the clock frequency of the PC, which is also just a non adjusted crystal ascillator.
I would be happy with the result.
Klaas Robers wrote:Yes, it is difficult to tune a crystal oscillator exactly onto his precise frequency. The main reason is that a frequency counter ALSO runs on a crystal.
What you did now is to match the frequency of your sync generator to the frequency of your computer. For your experiments this may be good enough.
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