Thread: RV and HF
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Old 06-09-2009, 09:22 AM   #9
wa8yxm
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One of the things folks forget is a dipole antenna is it's own conterpoise

So the O/P said "I use a couple of ham sticks

Like this perhaps: Stick 1------T------Stick 2

T is where the coax feeds

However from the post I don't think that's how he's doing it

I run 100' of copper wire myself, one end is hooked to the win nut on the KAT-1 Auto-tuner, then it runs up to a "hook" at the roof line of the motor home (or as close to it as I could mount) then it runs back to whatever I can find by way of tree or other support (Tree today), I'm parked in Davision, MI (Near Flint) and the AF4-net control for this morning's breakfast club 20 over on the old digital S-Meter.. I mean he was BOOMING in (Course he was the only one I could hear clearly ) Works great.

I've been net control a few times with that rig on another net. IN a much worse location too.

Don't do much on 10 meters though (I have an alternative antenna for 40 up if I wish)

For UHF I just put a NGP on the roof. sealed it in well (Servere T-Storm last night, no leaks) and for VHF I plan a quarter wave on the roof

I also have "T" poles (Based on the popular "J" pole) I can put atop a flag pole, they work MUCH better than the 5/8 NGP and I'm sure will beat the S-Units off the 1/4 wave too.. They are something that might suprise you a FULL WAVE antenna (Actually 2 half waves phased so they add)

The construction is simple 2 half wave elements, arrainged dipole style and a quarter wave of flat line (TV-300 ohm is what I usually use) as a phasing stub, the impedance at the dipole feed point is infinite (Well, in theory) so I short the quarter wave phase stub (Same as if it were a J pole) and tap up the stub to feed it, just like a J pole

In fact if I wanted a J pole all I'd have to do is drop one 1/2 wave element, the stubs are identical for both designs save mine is mounted at a right angle
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