If I remember right, the first rule in designing a BC antenna, when dirt was 
new, was PATTERN coverage.  Once that was achieved they fixed everything else. 
Resonance??????? No one cared.
Mel, K6KBE

      From: Fred Jensen <k6...@foothill.net>
 To: elecraft@mailman.qth.net 
 Sent: Tuesday, December 18, 2018 11:56 AM
 Subject: Re: [Elecraft] wire for random wire antenna using kx3
   
Indeed.  AM broadcast vertical antennas are rarely 90 or 180 degrees, 
especially if they are a Class A station.  I think both KFI and KNX in 
Los Angeles have 195 deg verticals.  The design goal is to maximize 
field strength in the service area, accomplished by adjusting the height 
of the current maxima in the antenna element.  All resonance means is 
that the reactive component of the impedance at the feed point is zero.  
A bigger problem for stations at the low end of the band ... KFI is at 
640 KHz ... is that the usable bandwidth of the antenna can be less than 
the bandwidth of the DSB signal. [:-)  Last time I saw KFI's tower from 
Interstate 5, it appeared to have a fairly large capacity hat.

Elecraft ATU's [even the KX1 which is necessarily small with a limited 
number of L-C selections] seem to handle reactive loads just fine 
suggesting [to me at least] that designing an antenna for azimuth and/or 
elevation pattern may be more beneficial than achieving resonance in the 
desired part of the band.

73,
Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 12/17/2018 7:45 PM, W2xj wrote:
> Coming from the broadcast side, especially AM broadcasting, I never 
> considered resonance particularly important. Really it’s just the transmitter 
> that cares. We always put matching at the antenna but in ham radio we usually 
> have tuners at or in the TX.
>

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to farrerfo...@yahoo.com

   
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Reply via email to