Broadcasters' Desktop Resource

... edited by Barry Mishkind - the Eclectic Engineer    


Is it time to eliminate the mileage tables from FM assignments?

10/4/11 - The FCC has received a petition for Rulemaking to amend 73.215 - which has been used to permit stations on the reserved band that are nominally short-spaced according to the separation tables - to include all stations.

The idea is to allow applications to no longer protect the maximum possible contours of an operating station, allowing other stations in areas where the existing operation, or terrain shielding, Another requested change that appears in comments addresses a technical anomoly where stations must assume in their calculations an antenna buried underground.

The FCC page where you can see the Petition and the comments on RM-11643 is here.

Here is a Guest Commentary by Dana Puopolo, CE of WURD, Philadelphia:

[10/4/11] Today I filed comments in an FCC proceeding where I proposed the Commission radically change the way FM stations are allotted and classified, and current stations modified. I also proposed a new Class of FM station.  Below is a copy of my FCC submission. I believe that it is well past time the Commission come into the 21st century. For example, the entire United States’ terrain data is digitized with 3 second or better accuracy, yet the FCC still relies on the 30 meter terrain data assumption it has used for the past 40 plus years.

The Commission still assumes that radios have 25 dB of second and third adjacent rejections (commonplace in the early 1960s when these rules were put in place)  when even the mid priced radios of today have rejections of better then 70 dB.

I believe my proposal is a good start - but it is only a start. If you agree (or disagree) with what I have filed-or have ideas of your own then I urge you to also file comments. The dialog is probably more important then the final results.

Before the

Washington, D.C. 20554


In the Matter of:                                                                    )                                                                                                                                                                                                   )
Amendment of Section 73.215 of the                                     )      RM-11643
Commission’s Rules, Related to Contour                               )
Protection for Short Spaced FM Assignments                       )

TO:      Marlene Dortch, Secretary
            Federal Communications Commission
            Attn: Media Bureau


 Pursuant to Section 1.405 of the Commission’s rules and regulations,

Dana J. Puopolo (“Puopolo”) respectfully submits his comments in the above captioned proceeding.  Puopolo is a broadcast engineer & technician with over 30 years of experience and has been an FM licensee. He has held an FCC Radiotelephone Operators license since 1974 and presently holds lifetime General Radiotelephone Operator License PG0114172.  His credentials are a matter of record before the FCC.  In support thereof the following is stated.
 1.     Puopolo supports the proposed amendments, but does not believe that they go nearly far enough. The FM band has long been hamstringed by obsolete regulations, many which are now almost half a century old. Puopolo proposes that the Commission examine EVERY FM rule-especially the rules with regards to FM allotments.
2.     Right now, proceedings to allot FM stations work strictly on mileage separations. This has limited the number of FM stations that could be allotted and has also made a waste of the Commission's time and resources. For example, in an FM allotment proceeding frequently a mutually exclusive counterproposal is filed, requiring the Commission to decide which proposal is 'more' in the Public Interest. Even after the Commission makes a decision, frequently there are requests for reconsideration and other appeals-meaning that it sometimes takes years to allot an FM channel to a deserving community. By increasing flexibility in the FM allotment process, none of these things need to happen. For example, the present allotment process uses an archaic system of allotment where second and third adjacent channels and IFs are concerned-when it is well known that stations can (and have been) successfully allotted on second and third adjacent channels both in the United States and other countries by using co-location, terrain blockage, etc. The same thing applies to IF spacings. The current IF rules were designed when vacuum tube receivers with slug tuned IFs were the state of the art-not the receivers of today that routinely have IF and adjacent channel rejections in the 70+ db range.


 Indeed, in New York, Los Angeles, Chicago, and other cities NON co-located FM stations of different classes have operated for decades on second adjacent channels without any problems. In Philadelphia, two stations are IF short spaced-and one of the two also is third adjacent short spaced with no practical problems.
3.    These rules should be intensely looked at and eliminated where necessary. Some will call this the "AM itzation of the FM band" -yet everyone agrees that AM is dying a quick death-and these proposals (coupled with a fair mechanism to migrate some AMs to FM much like is happening in Canada, Mexico and many other countries), might SAVE these local stations.
4 .   Puopolo proposes that FM stations should be allotted by the: 'where it will fit' philosophy that AM currently uses. Puopolo proposes that the second and third adjacent rules be replaced with protections based upon realistic for today interference ratios-and eliminated where stations of similar class have co-located transmitter sites. Puopolo proposes that directional FM antennas that represent the current state of the art be allowed to determine reference coordinates in FM allotment proceedings and all changes to current facilities. Puopolo proposes that FM terrain roughness (and smoothness) be allowed to be used in FM allotment proceedings and all changes to current facilities. Puopolo proposes the Commission determine FM station classes by the maximum contour distance radiated by an FM station on any bearing. Puopolo proposes that the Commission adopt a new class of FM station-Class A0, which would operate with a maximum ERP of 3 kilowatts at 100 meters AAT. or equalivent contour distance. Finally, Puopolo proposes the Commission allow stations that wish to receive (but not cause) interference made by other FM stations be allowed to do so-as long as the benefits of doing so are in the Public Interest.
Puopolo realizes this is radical, and will likely be opposed by the 'status quo' of current FM broadcasters who will claim these proposals he makes will hurt FM broadcasting. Puopolo does not believe this and instead states that what is currently hurting broadcasting is the exact opposite-those who oppose change.
Radio today is under assault from many directions-satellite, the Internet, smart phones, portable audio players and many other new technologies yet to ‘come down the pike’. Anything the Commission can do to make radio more vital is clearly in the Public Interest.

Respectfully submitted

Dana J. Puopolo
850 County Line Road
Bryn Mawr, PA 19101
October 4, 2011 



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