Stuart vs J-Pole
Ever since taking Eric Kehler's remedial class on 2 meter operation, I've been trying to get up to speed on that band. Among other things it is a good excuse to try one's hand at home-brew antenna construction, even if one has 3 left thumbs on the same hand.
When a Kenwood handheld tribander was purchased, I looked around for a homebrew triband antenna. The only one resembling on was a dual band j-pole found at:
Since this covered only 2M and 7cm, the link was stored in Favourites and left to be dusted off at a future time.
In July 2007 I purchased an Icom 208H dual bander and dusted off the plans on the website. After a trip to Home Depot for the copper piping and the parts, and the donation of two coax connectors from Lloyd Hobbs, the project was ready to go.
For someone with very limited skills in the handyman department, the parts were cut relatively easily and the thing went together as pictured. The soldering went well thanks to the loan of some propane from Ken Norman (VE7KBN).
Placing the feedpoint stub 3 inches up from the cross-piece of the J-Pole produced a 1:1.0 SWR at the midpoint of the 2M band, with SWR being 1:1.2 at the band edges. The feedpoint required no adjustment. The analyzer does not measure the UHF band, but so far reports are good and the 208H is getting out with full power.
Test QSOs are giving good reports for both bands and soon the antenna will get some height and become the main one for the home dual bander.
All in all an interesting homebrew antenna project. Give it a try and let us know how it works out!
Here are four images of the J-Pole antenna, click on them for a larger view.