[UK-CONTEST] : feeding beverages over long distances

[Dennis Andrews, F5VHY]

Beware of using 75 ohm satellite coax. I have tried feeding various receiving antennas with it and get some very strange results. This type of cable seems to exhibit strange resonances which I think are something to do with the type of shielding used in the cable. These are very obvious if you have the antenna matched through a transformer at the feed point and showing a flat 50 ohms across the relevant frequency range. Then put the antenna analyzer at the other end of the feed line and you will see all sort of dips and peaks that are not there when the same antenna is fed with RG-58 or similar. RG-58 is fine for RX antennas - you don't need to over-worry about loss in a lengthy line.

73

Dennis - F5VHY.