One problem i have over the last SSTV P7 and B/W NBTV magnetic deflected tube is EHT i have run out of Chinese bug zapper modules and this colour tube will need something a touch higher.
I did manage to have a look at the spark distance of the colour tubes EHT but it died before i could get my High voltage probe and better meter onit to take a correct reading .
Looked to be in the teens for a 1mm per 1000 volt spark .
Since then i have knocked up a replacement which i was going to do any case ,didn't use this crt's flyback transformer but used another i scrapped from another colour portable tv from a few years back ...its CRT is long gone which i regret all getting harder to find these days .
Below the ZVS flyback driver ,pretty much fool proof this fool as made 3 and they always work first go .
Now on to testing the voltage .
I had to check my meter and probe testing my PMT power supply on one of its settings just to make sure i remembered how this works ....i picked the PMT power supplies negative 1280 volts raw to the meter first up,then via the Probe and meter which shows 12.8 on the Low probe setting and 6.4 on the high (have to double the number on high setting).
Ok that went fine on to the ZVS flyback ...
Raw reading direct to my good high voltage meter its low voltage is a touch over 1.200 volts and high 12.050 volts via the probe working it out ....well so far , i have double the winding's on the primary coils i need to cut back and see if i can tweak it a touch higher
Below low EHT reading as the flyback driver starts to work. Notice reading is direct to meter .
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The highest reading it can do at the moment via a probe reading is 12.050 volts just add a zero via a probe reading
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low spark test ...not really good to do this all it doe's is heat your parts up to fail as i found out the hard way on this monitors original EHT circuit...i recall the 555 flyback circuits will kill them very quickly .
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Placement ...a pain if you make something and it doesn't fit a lesson learnt !
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The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.