In past posts, we have built several 2m portable antennas. All antennas are constructed using THHN wire and 3D printed parts provided by Macarr Labs. Each antenna was tested at the same height and using the same radio. Most testing was done simplex; but, some testing was done using repeaters.
The testing was very simple. A QSO was setup with several hams that were in different locations. Multiple transmissions were made and the audio quality was recorded. After each successful QSO, the power was reduced.
The 1/4 wave ground plane preformed well; but, it was beat out by the J-pole and the Slim Jim. This design does not have as much gain and it showed in the testing. Another disadvantage is, it was the hardest to store. The ground plane is difficult to coil up and keep neat. It also has the spreader bars that can be easily bent in the pack or while storing.
The Slim Jim fell next in my ranking. Performance was equal to the J-pole. There was no difference in audio reports between the J Pole and Slim Jim. When constructing the Slim Jim, it required a lot more adjustment to get it tuned. The extra wire also makes it a little more difficult to store. This antenna did have a little more bandwidth than the J pole though.
The J Pole is the antenna I liked best out of the three. Tuning was easier than the Slim Jim and coiling up the radiating element takes no effort. This antenna also requires less parts to construct. One small disadvantage to this antenna is, it has slightly less bandwidth than the Slim Jim. This is not a problem in my case.
More testing will be done with the J Pole. Future versions will be designed. It would be nice to wind the radiating element and tuning stub around a spool built in to the base. A connector will be nice so the feed line can be removed and stored separately. As this antenna evolves Posts will be made.
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