40W_BLF2047

40W BLF2047 PA:
Here is the 40W 2320MHz PA that is used for tropo DX during several years now. It is mounted in a waterprof housing at the rear of a 1.6mtr mesh dish. The BLF2047 is able to give a bit more power than 40W, but drive from the transverter is only 1W. A single stage amplifier like this is not able to have enough gain.

The BLF2047 transistor is mounted ona 1.5mm thick piece of FR4 double sided PCB material. Input and output are matched by means of lumped circuits.

The original description was published in the dutch HAM paper Electron.





 Here the mechanics are ready. The transistor is mounted on a 10mm thick piece of copper that serves as heat spreader. The housing is made from tinned plate. The input and output connectors are screwed to the tinned side walls.
The tinned box is screwed to the copper heat spreader by means of no less than 16 M3 bolts. To be able to screw the bolds in, M3 thread had to be machined into the copper. This took a lot of free time...


On this picture the PA is mounted behind the mesh dish. The supply for the PA is done through the PL259 connector, simple because a line to the shack was available that could run the 4A current that is needed (26Volt). The DC line consists of a spare H1000flex coax cable...