The original schematic says "13.8 V". I don't know now if it's possible to get 70 W at that voltage, though. Feels like too low voltage? The IRF530s might put out more power than the IRF510s for the same voltage though. My QRP Labs 50W PA (which uses IRF510s, also in push-pull) puts out 38 W at 19 V (not linear), for reference.
Here's a very nice write-up by F5NPV I forgot to mention before: https://f5npv.wordpress.com/irf530-mosfet-amplifier/ A lot of good information there (as well as the original schematic)!
Rasmus SA5RJS /
npub133…hfazx
2024-12-30 09:31:31
in reply to nevent1q…smd8
Author Public Key
npub133kx3vtsccvrn4uxjn85wacm45uqglre8qz7z7tr86p6lhy0whsqmhfazxPublished at
2024-12-30 09:31:31Event JSON
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"content": "The original schematic says \"13.8 V\". I don't know now if it's possible to get 70 W at that voltage, though. Feels like too low voltage? The IRF530s might put out more power than the IRF510s for the same voltage though. My QRP Labs 50W PA (which uses IRF510s, also in push-pull) puts out 38 W at 19 V (not linear), for reference.\n\nHere's a very nice write-up by F5NPV I forgot to mention before: https://f5npv.wordpress.com/irf530-mosfet-amplifier/ A lot of good information there (as well as the original schematic)!",
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