Saturday, May 31, 2014

2 meter J-pole in a tree

Finally, finally, finally getting around to installing an antenna for the Yaesu FT-1900R two meter radio I got for Christmas last November.

Copper J-pole is completely obscured by leaves. 
I didn't want to hang one off the house house, or in the attic. And I didn't want an elaborate antenna mast.

My house sits down in a hole. For most cellphone carriers, service is spotty. So for two meters, I knew I'd want at least a some height.

So I settled on a tree about a hundred feet from the back porch. The backyard has a gentle upward slope, so I gain height with every foot of cable run.

Mounted the J-pole on an 11.5 foot PVC mast, the first 10 feet is 1 1/2 inch PVC, the final foot and a half downsizes to one-inch. The J-pole is attached to the one-inch PVC. I used a ladder to get about 20 feet up the side of the tree, then hoisted up the mast so that the base of the mast is mounted at that 20-foot point. A series of metal air-duct clamps on the lower three feet of the mast now holds it in place.

Before installing the mast, I spray painted it a khaki color.  The paint didn't really stick well, and tends to scape off, but that almost seems to enhance the inadvertent camo effect. You really have to get up on this thing to see it.

I also put up a 10 meter dipole not far away. It's not nearly so stealthy. It hangs from a nylon cord hung between two trees. Got the cord over some branches by duct-taping it to a softball, and doing some underhand high pitches.

Update:  Mixed results when I hooked up transceivers. The 10 meter dipole works perfectly. Strong signals, and near perfect SWR readings. But there was high SWR (close to 2.5) on the 2 meter antenna. Part of the problem may be the proximity to the tree. But I also used cheap coax for the final leg of the cable run. Up in the tree. Live and learn, as they say.

Update 2: Checked out the cables except those making the climb up the tree, and still get bad readings using two different radios and a dummy load antenna. I suspect now it's the SWR meter that's bad, or perhaps just out of its range. Will look to acquire or borrow a better meter later in the week. For now, the 2 meter antenna will stay in place as is, pending further testing.

Update 3/Monday, June 2: Bought a Diamond SX-200 SWR meter at Ham Radio Outlet. According to the meter, the 2 meter antenna has a 1.1:1 SWR on a 146 mhz frequency I spot checked. Looks like the antenna build-out was perfect, the failing over the weekend was in the SWR meter initially used for check-out.

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