[BC] FM TX spacing question (cross-post)

[Mark Humphrey]

The requirement that a 73.215 applicant must assume short-spaced non-215
stations are operating with maximum facilities for their class sometimes
produces illogical results.

An application was filed recently by an upstate PA licensee to short-space
his facility to an adjacent-channel Class A station with a ridge-top site.
This station's actual HAAT is nearly 400 meters, but the 73.215 contour
analysis required an assumption of "maximum Class A facilities" of 6 kW at
100 meters, effectively pushing the antenna 250 meters (820 feet)
underground!  In this unrealistic terrain situation, the predicted contours
resembled a figure-8 (pinched in along the ridge) when, in reality, they are
much more circular.

If the applicant had been required to evaluate this station according to its
licensed mountaintop facilities (maximum Class A power for that height),
there would have been some prohibited overlap, but by "burying" the antenna
as required by the rule, his proposal was deemed acceptable and a CP was
granted.

Mark

On 2/7/06, rstype at aol.com <rstype at aol.com> wrote:
>
>
> Section 73.215 (the contour protection rule) is intended to provide
> stations with more flexibility in locating suitable transmitter sites
> and requires that the use of such a site involve the use of
> facilities which provide the required "contour protection" to short
> spaced stations.  In doing so, you must assume that the short spaced
> stations being protected are operating with the maximum facilities
> for their class (even if they aren't), unless the station being
> protected has previously used the contour protection rules to
> similarly protect another station (which effectively forfeits its
> right to be protected to maximum Class facilities).
>
>
>