[BC] Slant wire feeds vs series fed

[Scott Bailey]

Phil,
    If a exsisting daytimer, wanting to (or needing to) go to a slant 
wire antenna system, will they grant that? Now say if the daytimer 
has flea-power, say 2-10 watts, would they still allow the daytimer 
to use the slant wire feed?
    I've seen where this has been done on a emergency basis, and it 
worked just as good, or better than the old 1/4 wave series feed tower.
    I wonder.....what stations in the US are still using slant wire feeds?

    I'm using a unipole on my AM, but the slant wire, seems much more simple!



They would prefer seeing skirt fed shunt antennas instead.
While slant wires are not exactly prohibited in the rules, that is 
the effect of the rules in practice.
Slant wire fed antennas will not be approved for new nighttime 
service although they are permitted for new daytime use. HOWEVER, no 
new applications for daytime only service are being granted. Now I 
suppose if you had a two site operation, perhaps a DA-N site and an 
non-DA daytime site, they would approve a new application for the 
daytime site on that basis because the rules specifically say it is 
not prohibited.
It is far-fetched, but it could happen if the only site that would 
work for a frequency at night would not work for daytime in 
consideration of perhaps daytime adjacent channel interference. 
However, in that case, they probably would prefer a skirt to a slant 
wire because skirts are uniform.
There is a SLIGHT directional effect where the feed wire field tends 
to cancel the tower field however if the feed wire is close in (which 
force a higher attachment point) I think that should be very minimal, 
almost non-existent. The real problem, as I understand it, is there 
is no programming in the FCC computer for a slant wire feed because 
those programs predate the NEC. Thus, the FCC is unable to predict 
the high angle radiation of a slant wire at night. That, however, did 
not stop them from authorizing PSSA's and low power night service to 
Class III's back in the days of the show cause orders. So, there are 
quite a few of them in service at night, although none with more than 
about 240 watts, and most with far less.


Scott Bailey
General Manager/Engineer
Classic Broadcasting of Sumner County, Inc.
WMRO-AM, Magic 1560
Gallatin, TN
615.451.2131
615.202.0331 (Cell #)


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