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May 1, 2024. More output from your IRF510!

Every time I think or mention Mary Jo, somehow the 57 VW Beetle comes to mind. So, it is with the IRF510 and homebrew QRP rigs. They indeed are found frequently as the final RF Output device in our rigs. A really good thing that they can be had cheap -- as I have literally a ton of smoked ones sitting in a box. 



Today's sojourn is to document on how I took what I see as the common circuit for this device and by changing the Drain voltage to 30VDC from 12VDC, I went from 4 watts out on 40M to about 10 watts. I can also Drive my SB 200 to 150 watts out on 40M. This is huge! Now don't get too excited because the IRF510 on 20M may not give you that big of a boost but it will at least give you 2X. 

I ran this test a couple of weeks ago with a switching power supply and I could hear the supply in the radio. To resolve that matter I bought a used Condor 28VDC 1-amp linear (non-switching) supply from eBay. It does not have the noise issue and I got it for $25.
 
Add in a small sub-panel (scrap PC Board) a switch, fuse and power cord and we are there.








Without changing anything on the IRF510 board I got a huge boost in output using the same drive level. But as with all things more testing is needed. It is a possibility all we might have is lipstick on a pig. Looks to have great potential, but it is still a pig.

For AC wiring (110--125VAC), the convention is the WHITE wire is NEUTRAL, the BLACK wire is the HOT lead, and the GREEN wire is Protective Ground.

Always ahead of the curve.

73's
Pete N6QW


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