On 11/2/19 8:27 PM, Winfield Hill wrote:
Jon I wrote...

Since my dual 2N3055 driven flyback power supply was
accidentally thrown away, I was pondering building
another until coming across subject mentioned assemblies.

Haha, 2n3055, you're talking 45 years ago!!
For the last 35 years, we use MOSFETs.

They're on eBay and elsewhere. Looks like various drivers with
flybacks. Example: https://tinyurl.com/y4lzxt85 Questions ...

Might be cheaper to buy than to build another from scratch
so your thoughts/ experiences appreciated.

It's a shame they never provide schematics or similar
information. You do get a nice set of parts, and can
reverse engineer to get the schematic, and then start
making changes.

Interesting that there weren't more responses. I would have thought
some folks would have tried them out for the "tinkering" value alone.
And the cost would have covered just the cost of a single flyback, at
least of the kind I used to use. There are also the Chinese Marx
generators that appear to be driven by these circuits. They call them
"levels" when referring to number of stages with what appears to be 20
stage the highest level (20 level) offered. They specify "10-15 cm"
spark lengths with their "6 level" generator which makes sense with a 20
KV flyback driver circuit. There are videos around of the Marx
generators though, but hard to confirm spark lengths claimed.

Well, I had some trouble with the 3055's. Too much arcing at tripler
output would burn them out quickly and they way I had everything set up,
they were a pain to change out. I finally switched out to a more robust
transistor and had no more problems, but I couldn't tell you which
transistor that was now. It has been some time.