X-mtr locations that were granted to AM signals way back when

[qtpieislit]

WFIL, WNTP (WIBG), are up on the ridge as well as WNWR (RCP) due to S SE DA pattern configurations that offer a liberal signal footprint over most of what was primary population areas in the city proper. WHAT and WDAS were lower power allocations that required a signal footprint closer to Center City Philadelphia for primary signal coverage.

WIP's original tower was in Center City at 8th & Market on top of the Gimbels department store. Share timers 560/WFI & 560/WLIT (Strawbridge's & Lit Brothers) also had their towers on their respective department stores on market street as well as John Wanamaker's 1200/WOO

When WIP was granted 5,000 watts DA-2 they had to find a larger property to situate that antenna and did just over the bridge in New Jersey very close to Center City.

WCAU AM originally on 1170 developed the Newtown Pa site somewhat irrespective of the primary AM signal but to accommodate it's Short Wave Transmitter WCAB. When the short wave undertaking was dissolved to send the short wave transmitter over seas during WW2, they moved the AM to Moorestown.

WFLN had signal limitations and felt it was better suited to place the transmitter as close to Center city as possible.

WPEN found desirable property in Overbrook which was farm land at the time, to accommodate their liberal sweet spot signal footprint over Center City, for what was their early DA signal configuration

 

[rtetro]

Sam makes an important point. The location of an AM radio station's transmitter, particularly in the case of directional antennas, usually has more to do with their pattern shape than anything else. A directional AM will normally try to put their transmitter site in a location in which their major lobe is pointed toward their city of license and heaviest population density. In the case of WIBG, the Lafayette Hill area was pretty much the best location, given their two patterns.

The same is basically true for WFIL's day pattern and KYW, although to a lesser degree. They probably could have placed their transmitters in other locations and have been as largely effective. The limiting factor for KYW would have been the null toward 1050 in New York. Depending on the location of KYW's transmitter, this factor could have dramatically changed the shape of their pattern. The fly in the ointment for WFIL is their night pattern, which must be beamed largely to the SE.

Another factor for the location of WIBG, WFIL, and KYW is that, back when they were built, the population density in Whitemarsh Township was much, much less than it is today...similar to the remark made about WPEN's Overbrook site.

 

[vacuum tube]

Back in the day when most of those signals went on the air, the FCC rule was you had to have the 25mv/m contour cover the main business district of the COL. Now it is just the 5mv/m contour over the city of license, but they (FCC) routinely grant waivers allowing even less signal than the 5mv/m. Those Class D stations operating with secondary nighttime authorization (daytimers with low power) do not have to meet any minimum signal level requirment for that operation.

 

[rtetro]

Back in the day when most of those signals went on the air, the FCC rule was you had to have the 25mv/m contour cover the main business district of the COL.

I always believed that to be a good rule. It would be a real advantage today with the amounts of man made mega-noise on the dial. I was in center city last night for an event and was reminded again just how bad that noise can be in a major urban location. Thinking back to when I arrived in Philly for my first gig here in 1980 (WZZD), the static today along parts of Market Street, even under stations like KYW, WPHT, WNTP, WFIL, and WIP, is dramatically worse than 30 years ago.

It's hard to compare noise on WPEN's night signal between then and now because of the night transmitter move to West Norriton and power boost to 21kw. But, I can say from listening last night that it, too, is probably much more noisy than I remember it from the old 5kw Overbrook system.