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Antenna Mk-III Up And Working

Yesterday saw the implication of my Mk-III 9m long end fed random wire antenna.

Mk-I was a test of concept and consisted of a 5m long end fed random wire into a 9:1 unun strung between 2 light stands. This confirmed that (a) the AH-705 would match the antenna and (b) I would be able to actually receive a signal. I live in a tiny flat that is effectivly a massive faraday cage and stops all but the strongest signals getting in. Everything worked perfectly.

Mk-II increased the length of the random wire from 5m to 9m and removed one of the light stands (which kept blowing over in the wind) by attaching one end of the antenna wire to a ring screwed into the wall of my flat above my living room window (don’t tell the landlord!!). These changes gave me an overall improvement in performance and stopped the wind blowing it over.

Mk-III kept the same length of 9m but saw the addition of a car wheel over the base of the remaining light stand which massively improved stability and totally eliminated the risk of wind blowing over the antenna. This then allowed me to extend the light stand to it’s full hight of 4m and hight is always our friend when working HF. Additionally I took the weight and tension of the wire off the 9:1 unun connector and moved it down by 6 inches onto the mast because it was damaging the unun. And finally we added extra weatherproofing by placing a plastic bag over the unun and taping it down with gaffer tape. Simple but effective!

Mk-III gave no performance improvement other than getting the antenna a little bit higher overall but has given the antenna improved stability and resistance to the weather which means I can leave it longer between servicing.

Finally and most importantly I have to thank my farther for his help in carrying out this work. Without him I could not have done this.

LOVE YOU DAD