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#74 - New Antennas & Equipment

I decided to make a few upgrades to my equipment and my communications capabilities. First I will start with the updates to my antenna system here at the hamshack as well as for portable use and emcomm situations.


I have added a DX Commander vertical antenna which uses a 33 foot tall fiberglass mast surrounded by six wire elements for the 40, 30, 20, 17, 12, and 10-meter bands, but the 40-meter wire also works on the 15-meter band. It also has the ability to add an 80-meter wire in place of the 30-meter wire if desired.


Because this antenna uses multiple resonant wires as the antennas for the various frequency bands it acts similar to the way a fan dipole would excelt that it is turned on it side as a vertical instead of being stretched out horizontal. This antenna will be my main vertical antenna for the new BPQ32 bulletin board system and email server that I am setting up now, but I will get into that more in the next episode.


My main all-band vertical antenna right now is the 20' tall "Fat Spectrum" 13-Band vertical antenna which covers 160, 80, 75, 60, 40, 30, 20, 17, 15, 12, 11, 10, and 6-meter bands. I will keep this antenna as a backup for the DX Commander should anything happen to it.


I have also ordered a 50' fiberglass telescopic antenna mast for portable HF use. I am still deciding what antenna I want to utilize on this mast, I am considering an 80-meter dipole wire, fed by ladderline so that I can tune it for the 80, 60, 40, and 20-meter bands easily which are the main bands that I would be using in an EmComms situation.


I am also considering a fan dipole with pretuned wire antennas for each of those bands. I like that idea better, however by adding the additional tuned wires for each band, that also adds to the overall weight of the antenna. In this case I would basically be quadrupling it's weight over that of the single wire antenna.


Weight is a big issue when dealing with fiberglass antenna masts, especially one that is five-stories up in the air. Because Hawaii tends to get strong winds at times, especially during storms, this antenna mast will be secured by 21 guylines anchored at three positions around the mast along with a mast base anchoring system that is driven into the ground. There is also an alternate base plate version for when the antenna is set up on asphault or concrete which my communications van would be parked with the tire on top of the base plate giving it stability.


For here at the hamshack I have ordered two 40' metal telescopic antenna masts. For now I will be placing a G5RV Jr wire dipole antenna in an inverted "V" on one of them but I am considering replacing that with a fan dipole in an inverted "V" and an "L" configuration.


Setting the antenna up in an "L" pattern would allow me to have one of the ends of the antenna facing west and the other facing south. This gives me two benefits;


First it allows me to have a longer antenna wire. Because of the size of the property the antenna is being installed on I am limited to how long I can stretch a wire out in one direction. By taking the wire in two directions I can almost double the antenna's overall length.


Second, by stretching the wires to the west and the south I get closer to an omnidirectional coverage like a vertical antenna is.