[BC] Shunt Feed AM Antennas

[Phil Alexander]

On 24 Feb 2007 at 2:00, Alan Alsobrook wrote:

> I presume you are referring to a slant wire, (technically a unipole and 
> bazooka are shunt feed and are allowed). From what I've heard, if you 
> play your cards right you might could get one approved for daytime use 
> only. Since the FCC isn't allowing new daytime stations it doesn't seem 
> likely that anyone would want to jump through the hurdles that the FCC 
> would impose to a slant feed.

AFAIK there is no prohibition against a DAYTIME slant wire, shunt-feed.
Thus, it might be possible to convert an antenna of some other type to
slant-wire, but why? The problem would be that, as I understand it, the
FCC computer is not programmed for slant-wires, and this more or less
limits their use to the grandfather cases. One could make a case for 
using a slant-wire for its load characteristic which is broader and
flatter than most other antennas, but ....

BTW, the "bazooka" is not a shunt fed antenna, although the theory of
isolation is similar to a 1/4 wave skirt. A "bazooka" feed is a common
name for what the FCC calls "1/4 wave isolation" of a transmission line
crossing the base of a series excited radiator.


---------------------------------------------
Phil Alexander, CSRE, AMD
Broadcast Engineering Services and Technology 
(a Div. of Advanced Parts Corporation) 
Ph. (317) 335-2065   FAX (317) 335-9037