VE1ALQ 1.3GHz PA heatspreader

A friend asked me to make a heatspreader for the 23cm amplifier board from VE1ALQ (SK)

Rather than mess about with a sectional spreader, we decided to do a large single block of copper to maximise RF performance.

Millled to sized and flat, not drilling and tapping the holes
Holes and FET/load slots tapped and drilled, extension block for input load, and output coax clamp fitted.
Coax clamp and output hybrid dump load
Input SMA mount and outboard resistor mount for input hybrid
FET groove
Test fit of an MRF286 FET
The FET fits!
Main PCB soldered tothe spreader with tin/lead solder paste. Now applying Bismuth/Tin 138C solder paste for the FETs
On the hotplate with spring clips to hold the FETS in place while soldering
FETs soldered to the spreader and gat/drain connections solder to the PCB. Resistors are for gate protection until the rest of the components are fitted.

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