Antenna

My main interest is 144 MHz weak signal. The whole station is build especially to push the bounderies on that band. The current antenna at the homestation is a home made 14 element LFA antenna with 3 reflectors. The gain is 14.48 dB (16.63 dBi) and the front to back ratio is 36.35 dB. This antenna is a compromise as I can work all forms of propagation including Earth-Moon-Earth. It is also what is accepted in my neighbourhood as it can be seen from all around. The boom is 30×30 thick-walled aluminium as it is nearly 10 meters long. The return-loss is better than 53 dB at 144.150 MHz.

4 x 14 element XPOL LFA antenna

To keep things at a lower profile I have made a stack of 4×14 element (7H/7V) XPOL yagi’s. The total gain of this setup is 16.66 dB (18.81 dBi) which is about 2.5 dB more than my single 14 el LFA PLUS2. It makes it possible to use horizontal or vertical polarisation and in combination with my Javornik 144/14 duo channel transverter, the Afredi 822x SDR and Linrad 4.07 I have adaptive receiving capabilities. The stack up is easy to set up and can be used in portable operations too. Being low on the ground means I pick up less noise from solar panels from neighbouring houses. Sometimes, especially when Tropo is good for several days, the setup is placed on the flat roof of our house. In the technical corner you will find details how to set up an adaptive receiving system for Earth-Moon-Earth.