G3WDG amplifier WDG050

Steve Bunting M0BPQ

Hi everyone,

I have a G3WDG 50W amplifier for 1296MHz that does not have an integrated 5V bias circuit.  As I'm a talent-less designer, can anyone point me towards a PTT switched bias circuit that I can build? The PA runs on 28V.

I would also like to box this up with a preamp for mast head use - my coax runs are very long. I assume the general wisdom is still to feed 28V up the mast rather than 240V? I was thinking about copying M1BXF's approach ( but I wonder if this is suitable to leave up the mast 24/7 as compared to Gav's box which is used contest portable.

Steve, M0BPQ