Keith successfully completed his POTA activation under a gorgeous blue sky at the San Jacinto Battleground Historic site on Wednesday March 19. Keith deployed his homebrewed multi element Chameleon Spider antenna. This is a variation of the buddipole design, using a pair of rigid elements to form a dipole. However, the Chameleon Spider can be configured for up to 4 pairs of matched Ham Sticks (for a total of 8 ham sticks fanned out from the hub) to allow instantaneous band changing across 4 bands. These 4 bands are defined by whatever ham stick bands you decided to screw into the 3/8″ ports on the hub. The hub is agnostic with regards to which bands you decide to mount on the antenna (6m-80m). However, for this to work, a ham stick of a defined band must be paired with another ham stick of the same band on the opposite socket on the hub. i.e. a symmetrical dipole must be formed for each band used.
OK, I’ve never seen one of these before. It looked very cool, and its installation was a breeze. Did it work? … YES. Keith had multiple pileups on 20m SSB using this antenna. His Spider was only about 10 feet above ground (no radials needed) and worked terrifically. To keep his deployment simple, he only installed an additional 10m pair of hamsticks.
In a few hours, he almost cleared 60 QSOs. We QSYed to 10m and received a 59 from Connecticut, but the band went dead so we never had an opportunity to try it out more on this band.
Of note, this type of antenna is top heavy which was one reason we kept it at around 10′ elevation. I reminded Keith that this and many other POTA parks disallow ground penetrations that we hams like to use of guy stakes. If we loaded this spider up with its full complement of 8 hamsticks, guy wires would probably be needed. Although this worked great at 10′, it would be interesting to get it elevated up a bit more.
In addition, the exciting experience of using this new antenna, Keith aired out his IC-718 Icom transceiver and at the end he activated his newly acquired Icom IC-706MK2g transceiver, which worked great as well.
The attached photo shows the build detailed inside the hub. Keith procured the waterproof octagonal hub from DigiKey and drilled out hole to fit the 3/8″ stud mounts. The simplicity of this design is apparent: the feedline SO-239 center pin connected to 4 insulated 3/8″ ports and the ground lug connected to the opposite 4 ports.
The highlights were getting called by an aeronautical station flying 40,000 feet above Alabama and how unexpectedly well this antenna performed.
As usual, 20m was quite good during the morning and puttered out as the day got old.
Cool antenna setup, and I never thought the hub for something like this would be SO simple! Wow.