Help & Advice

I'm not familiar with low pass filter cf30mr.

I put 9 turns of my HF antenna cable on an FT240-31 outside the shack. It is on the wall in a grey box - bought from Screwfix. Endfed has a counterpoise that is 1/20 of lowest band e.g. 80m = 4m - it is on the other side of the antenna on 49:1 and dangles down but does not touch the ground.

NB using an earth to ground isn't always effective - it can appear as an inductance and an earth rod may not provide the low impedance depending upon ground (soil) and other factors.

I also put an FT240-31 with 6 turns on my PSU mains cable (L + N + E). I would have put 9 turns but I needed the additional length.

I also put an FT240-31 with 9 turns on the output side of the PSU - both the red and black wires.

I haven't needed an FT240-43 so far because the FT240-31 covers 80m-6m OK.

PSU is a switched mode version. It has a mains earth for the metal case and the common (black) wire is also earthed. The RF earth terminal of the radio is connected with 10mm cable to a 4 foot copper earth rod. RF earth is connected through to mains earth - not ideal but seems to work OK.

I also have a lightening arrestor for the HF antenna - also connected to the earth cable to the earth rod. For UHF/VHF I'm in the process of installing a second lightening arrestor. Better than nothing and bleeds off static but a direct hit would probably destroy the cables and/or some equipment anyway.

Simon
M7CKL