I finally finished my new 2 meter 5/8 wave whip antenna, tested it and installed it on my roof. I got the design from the 1986 ARRL Handbook. It’s a very simple design, but with everything else, it took me awhile to get everything together. The original design called for a 3/4″ x 3 1/2″ acrylic cylinder, but I wound up using a short length of 1/2″ PVC (approx. 3/4″ OD) with a screw on cap. Later it occurred to me that I could have used one of those acrylic toilet plunger handles. Maybe I’ll switch to that when I install it on my truck. For now, the PVC is working just fine, and I’m sure you could use pretty much anything close to the right diameter and is non-conductive.
I had some trouble understanding how to actually connect the antenna to my radio and how to mount it. The tap on the 4th coil is soldered to the point in the SO239, while the ground at the very bottom of the coil can just be screwed down to whatever you’re using for your ground plane. After some thought, I understood that that means the antenna assembly itself doesn’t have to affix to the ground plane. Mine is zip-tied to a 2×4 that is in turn zip-tied to the vent that my feed line feeds into. I’m not sure it’s totally necessary, but I also connected the outer part of the SO239 to ground. Whether or not it’s necessary, it doesn’t seem to hurt anything.
It performed well for both RX and TX during the initial test on my balcony, and I have now tested it in it’s semi-permanent home on the roof. It works great. The roof acts as a giant ground plane just as expected. The vent that it’s attached to comes into the back closet where my little ‘shack is which is absolutely perfect! I have leftover cable from a 20’ line!
I apologize for the one terrible picture. I don’t know what I was thinking. I’ll update the picture when I install the 11m or 10m dipole.
Next up, 11m half wave dipole for and old CB radio that was my Dad’s. If the radio works, I want to modify the radio to 10m. It should be relatively simple since it’s a PLL (Phase Locked Loop) radio.