[Hallicrafters] Snow / Antenna question.

[Duane Fischer, W8DBF]

Al,

What a terrific and comprehensive response! You always have, and always 
will, amaze me with your grasp of electronics on all levels.

Duane Fischer, W8DBF/WPE8CXO
dfischer at usol.com
HHI: Halligan's Hallicrafters International
http://www.w9wze.net
HHRP: Historic Halligan Radio Project
hhrp.w9wze.net

----- Original Message ----- 
From: "Al Parker" <anchor at ec.rr.com>
To: <hallicrafters at mailman.qth.net>; "Waldo Magnuson" <magnuson at mac.com>
Cc: "Waldo Magnuson" <magnuson at mac.com>
Sent: Saturday, February 02, 2008 1:13 PM
Subject: Re: [Hallicrafters] Snow / Antenna question.


> Hi Skip,
>    Your SWR might be up a little, that would provide a little more loss in 
> the feedline, and generate a little heat, but I don't think you'd get 
> much, if any, heating in the wire of the dipole.
>    I guess you could look at it as there is RF current flowing, but the 
> resistance of the wire is so little that not much power is dissipated in 
> heat, as an IR loss.  Center fed dipole has highest current at the 
> feedpoint, zero at the ends.  Figure pwr = I squared times R, so I = sq 
> root of pwr over R, or I =s q rt of 100/50, or I= sq rt of 2 =1.414 amps. 
> If it's #12 wire, and has 1.619 ohms/1000ft, or 0.00169 ohms/ft.  Then the 
> pwr dissipated in the first foot would be approx.  amps squared times 
> resistance, or 2 x .00169, or 0.00338 watts.  Not very much.  #14 wire 
> would give a 'hair' more (scientific term there).
>    I'm sure somebody will correct me if my math or reasoning is wrong.
> 73,
> Al, W8UT
> New Bern, NC
> www.boatanchors.org
> www.hammarlund.info
>
> ----- Original Message ----- 
> From: "Waldo Magnuson" <magnuson at mac.com>
> To: <hallicrafters at mailman.qth.net>
> Cc: "Waldo Magnuson" <magnuson at mac.com>
> Sent: Saturday, February 02, 2008 11:50 AM
> Subject: [Hallicrafters] Snow / Antenna question.
>
>
>> Spokane, WA has been getting a lot of snow this winter (about 70 inches 
>> so far) and yesterday my horizontal 40 m dipole had about 2 or 3 inches 
>> piled up on it (and it did sag a little).  My transmitter is currently 
>> undergoing some repair so I couldn't check but I know some of you will 
>> know the answer to this question.  Will transmitting on 40 m at about 100 
>> watts do any warming of the antenna and remove the snow?  Thanks.
>> 73,  Skip  W7WGM
>>
>> ______________________________________________________________
>>
>
>
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