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Put new flyback driver on my website
Original poster: "rob by way of Terry Fritz <twftesla-at-qwest-dot-net>" <rob-at-pythonemproject-dot-com>
I finally got very high voltage from my NOS 70's color TV flyback. I
put the schematic on my website below in the "Coil Corner" section.
However, this circuit is not sustainable. I draws 3-5A at 30V. I think
if you turn down the voltage it might be easier on the components. The
key to using a modern HV switching transistor was to heavily damp the
transformer. Otherwise the short switching times of the best bipolars
would ensure their own destruction. Ironic. (a 2N3055 was slow enough
not to self destruct :)
The two points of concern are: 1. Use a transistor mounted directly to
a large DC floating heatsink. Do not use a mica or rubber insulator.
Beryllium oxide might be OK. 2. The circuit generates such large
magnetic fields in the flyback (0.5 to 1mm gapped ferrite) that the
metal brackets get very hot from induced current.
I still want to work on this circuit some more to get some pulse shaping
in the base circuit. Narrow pulses at the resonant rate is what gives
I tried to fully characterize my flyback using an LCR meter. Doesn't
work very well when the secondary has 520 ohms.
The Numeric Python EM Project