[BC] AM Band Birdies Chart

[Mike McCarthy]

I concur with Curt.  In 20+ years of radio, I've only had to deal with this 
once.  It's simply an A+B summed mix condition in the RX.  That is most 
often the case in RX BFO. Similar to RITOI, but one step short.

One of my former stations gets hit with two A+B combos from different 
directions and they constantly complained thinking the engineer could do 
something to fix "the coverage problem in those two areas". Over the years, 
they added more copper to the ground (they have over 400 radials from 4 
different iterations of radial installations.) and tried a variety of other 
"fixes."

When they wanted me to contact the FCC about being interfered with, I took 
them out with a FIM and had them listen to their supposed high end car 
radio with all the IM. Then I did the same with a FIM. Guess what...zero 
interference.  Expression...priceless.

We then went to less than 0.5 mile from one of the 50KW co-contributors and 
did the same.  There was only about 1.5mV of signal at that point. Yet the 
FIM still RX'd the station fine. The car radio was useless. That was the 
last time I heard them complain.

Bottom line, don't sweat the issue if there's no one complaining.  It's a 
non-issue in the vast majority of the stations out there.

MM

At 08:43 AM 11/15/2005 -0500, Cowboy wrote
>On Tuesday 15 November 2005 08:24 am, Stanley Adams wrote:
> >Where can a fellow find a chart of calculated birdies in the AM broadcast
> >band, i.e.:  2F-1F= for example 810 kc.?  Or F1-455=such and such.
> >
> >Some are easy to figure out in your own market, but I bet that there is
> >a chart out there with all of the possibilities.
>
>  I'd be surprised.
>
> >I would think that some very wise people have such a chart as the band is
> >about three octaves in length.
> >
> >Is this a stupid request?
>
>  The thing is....
>  If you want all possibilities, and since you tossed in 455 as well, you can
>  find combinations that will produce every 5khz from 5khz to a bit above
>  5Mhz, and that's JUST the third order stuff !
>
>  It's just easier to do it ad hoc when the situation arises.
>
>--
>Cowboy