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Re: Topband: Effect of trees- tree appreciation

To: "Rick Stealey" <rstealey@hotmail.com>, <topband@contesting.com>
Subject: Re: Topband: Effect of trees- tree appreciation
From: "Tom W8JI" <w8ji@w8ji.com>
Reply-to: Tom W8JI <w8ji@w8ji.com>
Date: Thu, 8 Aug 2013 12:40:06 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>


Just thinking here - I can hold my hand on a 75 watt lightbulb for a few seconds. 10 of those lightbulbs-worth of heat isn't very much heat, dissipated over the surface area of the bark of a tree, 60 feet tall, in winter, with low temps, and maybe even some wind can't really have much in the way of visible impact, could it? Gone up in flaming glory?


Good logical thinking. It's difficult to know a 6 dB change without measurement, let alone three dB.

Take a tank coil as an example. Even 50 watts of loss could make it smoke or melt if the loss is concentrated in one small area, say just a few turns. If loss is spread over enough area, even 1000 watts power loss might not be noticeable.

This not only applies to trees, it applies to everything from ferrite cores to transmission lines. 0.1 dB loss in a coax connector can melt it down at amateur power levels, 10 dB loss in a 100-foot cable might be unnoticeable.

73 Tom
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