Steve Ward Half Bridge and Micro SSTC Action

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Back at it at least for the moment. While I forgot where I was originally going with this I ended up putting together a voltage doubler after finding a couple large caps I had in a scrap box. What I do remember is I was going to try to build a more sophisticated and powerful ZVS supply I could pull 300VDC or so from to drive some coils. Never got around to finding a proper core but for the time being the voltage doubler gives me around 200V which makes a noticeable difference in the output compared to the 170VDC I get rectifying the variac output. Long story short I do a lot of changing around of things and I get tired of replacing 5A fuses when running CW. Observing how the voltage drops on the ZVS output can let me know ahead of time whether something just isn't going to fly off a 5A fuse and mains input. I can also drive the whole thing from a battery powered supply @30VDC input if I wanted to with the ZVS doing the inverting.

A big issue is getting around the arcing of the primary where it seems like that's going to be the problem pushing higher voltage instead of components failing. This kind of arcing is always a problem when I get coils firing decently and it usually seems like with preferred setups it's just impossible to 100% insulate the primary without some kind of vacuum potting or some crazy shit.

I also ended up getting my Micro SSTC driver interrupted using the NAND gates like I did with the half bridge and it works pretty good. Gets iffy at over 170 and the primary arcing makes it unstable but it gets pretty impressive output with the one shit IRFP460 I got from ebay eddie.

Wound the new coil for my other Steve Ward 30V Micro SSTC and it works like a champ. I still don't know if using the hex inverter makes any actual difference but I do drive mine from straight DC unlike Steve's circuit which uses the smoothed DC from a transformer. I can pull some decent hot arcs from it at 30V for less current than I can from my other 30v coils but the mosfet did get too hot without a fan.