stuwee said:
1930's mono AM with toobs and a big honk'n woofer!
Not just AM (standard broadcast bamd-BCB to 1500 KC) but also police band to 1800 KC and some shortwave ("foreign") likely to somewhere between 16-18 MC.
FM was an experimental service in 1937, mostly former Apex service stations in the 20-26 MC band and the pioneering stations such as the Armstrong led "Yankee Network". At the end of the 30s sets with a standardized FM band in the 40-50 MC band began to emerge...these sets would have to be modified or replaced directly after the war when the FCC moved them into their modern band. at first 88-106 then expanded shortly after that to 88-108 MC with the current 88-92 noncommercial band.
Armstrong was livid about this but obviously it made sense as it was conveniently between channel 6 and 7 (already an enpty spot then), out of a tough area in LOW VHF where the original channels 1 and 2 had a hard time from skip/interference and taxi radios among others and even at 54-60 MC channel 2 took savage periodic hits.
So relocation seems bad, however what was worse and almost killed FM involved the circular motions of many stations simulcasting just to be there in case AM took a dive. Original programming was not sustainable without set sales. Set sales would not materialize quickly for the price and perceived notion that all they wanted was on AM and FM was a poor stepclild. Postwar AM was driven by MUSIC and advertisers flocked to the hot stations. Nobody would buy FM and listen so advertisers would not buy FM time.
The remaining option was to simulcast and combine spot times for a dual station rate card. This killed off FM listening when the audiences would become discouraged that any original content was not happening, thus coming full circle.
That is not to say that no unique FM services existed. Like UHF, the operations became weighed down in losses and support and stations were dying left and right. The FCC saw this conundrum and acted to try and increase FM success. Unlike TV however, beyond the non-commercial allocations and some shuffling of allocated frequencies in the 1950s within the existing 88-108 MC band no requirements were made regarding which bands were used for which city allocations. Simulcasting was banned outside of small markets or severely limited though.
AM simply bareled down the road. It had the sponsors, the popular formats and personality announcers, also called disc jockeys. Many serious attempts to introduce stereophonic AM were proposed in the 50s, some very close to those that emerged in the early 80s but the FCC held them off. They had FM stereo of some type in mind.
FM alone did not save itself. The MPX system launched in 1961 didn't do it either. The establishment of quality formats that used both and brought listeners and advertisers alike to the station did.
In my market this was not easy. The first two stations in Idaho were born in 1946 and quietly died before 1957. When FM began to catch on there were still only two stations here from 1961 until 1967. By 1973, only FOUR. Not until 1975 would new stations begin airing to the point of over 20 with out of town stations slingshotting into the market and moving in (something that is not very possible now since the FCC has passed rules to discourage moving stations out of town or crowding boosters in (slingshotting).
AM hasn't died out here either, We've lost but one station in 84 years and it was the only new allocation since the 1960s, not a reassigned frequency. You don't lose a station here, it's like rescuing a maiden.
You didn't see Wikipedia coming I'll bet.