Got another amplifier project on the go to learn more about them, this time made completely from scratch.It uses 8 x IRF520N mosfets and works up to 20m and will deliver a significant amount of power. Its designed for 250W, but I have had over 400W out of it!!
View of completed module
Drilled heatsink, nicked from an old audio amplifier. And thermal pads.
Underside of amplifier
Start of development of amplifier controller
The amp has an RX/TX circuit on there so is usable at the moment with a suitable LPF for the band required. Developing a controller with ADCs etc for monitoring SWR and current and TX sequencing. Once tested and working with this smaller amp, it will be used to control the big EB104.
Output transformer is made from ferrites that were clipped to power leads in a dead switch mode audio amp.
It runs off any voltage up to 30V, 24V has been chosen for high power mobile use at 300W. At 13.8V, over 100W of power is available up to 20m.
Total cost very low, £50?
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