170 Watt 80 metre Transmitter Receiver

The first photo shows the two 1u shelves of the transverter sitting on top of the h/b 3u 80m qrp (3 w) cw tx/rx. The transverting (mixing) functions were turned off and the only modules used from the transverter were the Norton broadband receive amplifier and the linear amplifier. The linear produces 170 watts output on 80m (it gave 130 watts on 20m) and the next picture shows the linear amplifier splitter, high power combiner, 2 x dual Mosfet amplifiers and dual switch mode power supplies.
The third photo shows a close-up of the 170 watt combiner and the input circuit of one the linear amplifiers. The 4 x IRF510 mosfets have proved very reliable (at a lower power level). The antenna (capable of handling up to 3 amps peak) and an 80m dipole was built using 300 ohm ribbon with the two conductors connected together. The 4th photo shows the dipole centre piece made from a chopping board.
The DC rx in the QRP rig makes it difficult to copy cw in any but the best conditions for a DC receiver, i.e. no transmission on the adjacent sideband etc.

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