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Antenna Modification

At the moment I have VERY limited space to put any sort of antenna up on a long term basis. What I have now is a 9m long random end fed wire going into an LDG 9:1 Unun about 12 feet off the ground and located in a gap between my block of flats and a high banked wall. Far from ideal but I’m actually getting really good results from it. Out west I’ve reached Alaska and get regular FT8 contacts into the east coast of the USA and Canada. Out east I’ve reached over to the Russia/China/Mongolia boarder region using FT8 on both 10 and 50 watts. And all over Europe I never seem to fail getting SSB voice QSLs on 10 watts with excellent signal reports.

I’ve been out today to give the antenna a bit of a check over and service and to add a large counterweight to to bottom of the mast stand to abb stability.

While out there I’ve realised I need to make a little modification. At the moment the weight and tension of the wire is entirely supported on the banana plug going into the top of the 9:1 unun and this doesn’t seem to be a good long term solution. The plug is pulling out and the unun case is bending.

So, I need a new 9m (maybe even up it to 10m) length of wire with about 12inch extra wire on one end. I’ll support the tension and weight of the wire on an isolator directly attached to the mast rather than the unun and then use the extra 12inch bit of wire to plug into the unun thus reliving the tension and weight from the banana plug and the unu case combination.

I will also add some sort of weather protection to the unun which will probably end up being a plastic bag and a long length of gaffer tape. Crude but effective!!

LDG 9:1 Unun