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In a previous article available HERE I described the construction of The 2m Oblong (rectangular loop) Antenna. I decided to revisit this very easy to construct antenna. This antenna is a very popular antenna in parts of Australia and is mainly used for SOTA. It is easy to make, light to carry and packs small. It is horizontally polarised. (Note: Repeaters use vertical polarization.) The Oblong Antenna I constructed resulted in the following NanoVNA readings:
144.000 Mhz 60 Ohm VSWR 1.2
145.000 Mhz 53 Ohm VSWR 1.0
146.000 Mhz 51 Ohm VSWR 1.0
From the above it is clear that the antenna needed to be lengthened if you want to lower the resonant frequency. However I am more than satisfied with the resonance frequency of the antenna I built and will leave it just the way it is.
An RF Choke is not a bad idea to keep the RF at the antenna. If required wind 8 turns of RG58AU coax around a 25 mm former. Make a 1 turn loop near the feed point for strain relief on the coax BNC plug.
Testing:
I once again tested this antenna using my trusted UV82 radio and could access all the local repeaters in the George / Mossel Bay area with three watt output. I was not able to access the Aasvoelkop Repeater from my QTH using 3 Watts output power. Remember this antenna is horizontally polarized while the repeaters are all vertical polarized. Polarization clearly played a roll in this regard. Maybe I will change the polarization in the future just to see if I can access the Aasvoelkop Repeater with this antenna. Remember horizontal polarization has less RF attenuation than vertical polarization at the same output power level.
Final Comment:
This antenna will be great for HOTA, SOTA, POTA and even Emergency Communications. Although it does not have gain like a Yagi or a Quad Antenna it is ideal for a cheap, quick, light weight and minimal setup. Distances of between 60 and 94 km has already been achieved using this antenna in difficult terrain.
Note: This antenna is mainly for use on SSB and CW.
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