[VHFcontesting] Height vs. foliage

Rhinosix rhinosix at aol.com
Sat Jul 30 14:33:48 EDT 2016

We are looking into a solar min for the next 5 to 6 years so putting big bucks into a super antenna setup on six meters at this time may be disappointing.
For 2 meters and 1 1/4 meters there is tropo for the 200 to 300 mile contacts.  There is Trans equatorial in the Fall and Spring for some long haul contacts.  For uhf height is everything.  You say you have some good size trees to work with.   What I have done is put up some delta loops (2) at 40 ft.If they aren't too far from your house feed them with coax.if they are 100 ft or more use window line, 4:1 balun and coax (short lenght) to your rig  use a coax switch for bidirectional operation.  You may also want to try a double H loop on 6 meters too. This setup has gotten me a lot of grids over time.  But if you interest is only in competive contests you are going to have to spend some $.
The alternative is just learn to love the HF DX.
Jerry W2JCN





-----Original Message-----
From: Patrick Thomas <p-thomas at mindspring.com>
To: vhfcontesting <vhfcontesting at contesting.com>
Sent: Sat, Jul 30, 2016 7:44 am
Subject: Re: [VHFcontesting] Height vs. foliage

Wow, thanks for all the feedback.  It sounds like the anecdotal evidence varies, so maybe I need to look up those absorption articles and spend some time to do objective calculation at my frequencies of interest on:
1) low-height, high gain, attenuated by trees (what I have now)
2) medium-height, lower gain, attenuated by trees (hanging a halo stack, off a tall branch)
3) medium-height, high gain, attenuated by trees (current antennas on modest or roof tower)
4) substantial height, not attenuated, high gain (best but expensive)
(or moving!!)

...and figure out much each jump is worth to me, and how long I want to wait to afford it.  At least #2 (and maybe #3 using the roof) is likely to be affordable in the short term.

Which moves my question to "where is there good information about attenuation effects of trees?"  I'm sure google can help, but I'd be glad to weight ham-proven options appropriately.

The next-to-the-house versus away-from-the-house tower discussion is probably its own topic of debate.  On one hand I'm not fond of fastening a big lightning rod to the house... especially since the house's presence compromises RF and lightning grounding at least somewhat, and concern must be taken for one's basement/foundation.  On the other hand, bracketed installation means less feedline, easier access, and it provides better structural support.

Modifying the trees is not really feasible due to their quantity, size, and proximity to the house.

My city will require a permit, so the installation will need to meet mfg specs and local height restrictions, not just "other people have done it and nothing's blown over" or "it doesn't seem that tall from the street." :)

Thanks for the ideas & info!

Pat - KB8DGC

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