Moderators: Dave Moll, Andrew Davie, Steve Anderson
Harry Dalek wrote:I expect a viewing range as below what i can produce
405 10.12khz 50hz
240 12.82khz 53.44 hz
441 11.04khz 50hz
625 15.65khz 50hz
525 15.70khz 59.79hz
625 1500x580........15.60khz 49.92hz
107 2.674khz 25hz
819 20.52khz 25hz
120 2.677khz 25hz
Steve Anderson wrote:
Hi SteveI'm curious as to how you plan to provide a signal source for those various line and scan rates...two are easily generated or maybe you have a source already (525/60 & 625/50), the others need some thought...
Steve Anderson wrote:I would need to look into that "Mode-Line" program myself, if it does what is says, well, it could be a valid source of signals. Where can I download it from?... I know you've mentioned it before...
As for the voltage multiplier, that could be done in fewer stages depending on the transformers you have and if they are required to provide other supplies as well.
Steve Anderson wrote:It's true that certain precautions need to be taken with Cockcroft-Walton voltage multipliers, or any other multiplier. Here's my 'check-list' when I build one...which isn't that often...
1) All capacitors are new, ordered from the same supplier in one order (a good chance of a batch-match). They therefore should ideally all the same.
2) They all should have a voltage equalising resistor in parallel with each capacitor, but otherwise no load.
3) Once built, arrange some method of slowly raising the 240V supply, say 50V to start with, check voltages and polarities across each cap (and write down) are approximately equal, leave for an hour, check again.
4) Increase input voltage to say 100V, repeat above exercise...
7) Repeat the above at least three times and compare results, allow some 'rest period' (hours) between tests so that the caps completely discharge.
Lastly add the real load or a simulated one (a big suitable resistor or array).
9) By this stage the caps should have 'formed', they may have been stored for years, this is a gentle way of doing it.
10) Now if all the above looks good you should be able to apply the full mains voltage at switch-on without any problems....says he!
Steve Anderson wrote:No idea what's inside my PC, all I know there's two HDMI outputs on the back of it....I've never bothered to look inside...it works as I want, that's that! I have a similar attitude when it comes to cars. But motorcycles and aircraft I treat very differently...
I mentioned that the caps should be new, therefore unused, hence the gentle 'forming' process. Just because they are 'new' and unused to you, they may have been in storage for some years.
Steve A.
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