For any errant VHFers who live here, THE VHF/UHF DX BOOK edited by G3SEK,
published for the RSGB and available from the ARRL, contains an
absorption(db) vs frequency (30-3000 mHz) chart for foliage. Not exactly the
same as redwood trunks, but interesting reading nevertheless.
-Herb,W3IWU
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At 08:47 12/13/96 -0600, Craig Clark wrote:
>At 04:53 PM 12/12/96 -1000, you wrote:
>>The military has done extensive studies regarding RF absorption
>>by foliage. 20 years ago while in Coast Guard Radioman school
>>I recall some instruction regarding this; my memory is a bit
>>dim but what stands out is that all antennas should be kept
>>clear of all growth, and don't depend heavily upon ground
>>wave propagation over forested areas.
>
> "Don't sweat the small stuff"
>
>I remember this too from US Army Signal School, fall 1974. However, the key
>factor was frequency. Since most platoon and company communications is VHF,
>this was the frequency range of greatest concern. PRC 25/77 series radios
>use either a long rigid whip or a flexible steel antenna (the one you often
>see bent over the RTO's shoulder.) The long whip was better for covering
>greater distances. The steel whip is, at best, like a rubber duck,
>convenient but not the best DX antenna.
>remainder deleted
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