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Developments to preserve "FrankenFMs"

IIRC, the Franken FMs are allowed to use the FM broadcast format (75kHz, 19kHz stereo pilot) instead of the NTSC FM format (25kHz, 15.734kHz stereo pilot, dBx NR), may as well go all the way and let the Franken FMs use 87.7MHz as the center frequency.

NTSC TVs may provide distorted sound from Franken FMs and also wouldn't provide stereo, so compatibility with legacy NTSC audio isn't much of an issue.


Kirk Bayne
 
Theater of My Mind said:
TV channel 6 analog audio has always been a sort of radio reception hack. It's off-frequency for most digital tuners. Some sound OK tuned to 87.7 or 87.8, others don't. The Franken stations used it anyway because that's the audio frequency allowed by the TV license and it worked well enough to get the job done on FM, even if it wasn't perfect.
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This. The use of TV analog channel 6 back in the day was to get on the FM band for cheap. In modern times, nobody but a few radio nerds would go looking for a carrier at that end of the band. That's why most have gone the way of the Dodo.
The thought of some channel 6 VHF going ATSC 3.0 modulation is about as likely as the Catholic Church recommending Christmas be changed from December to August. Doing anything ATSC 3.0 is not cheap, so the motivation just isn't the same as it was what.. over thirty years ago?
Theater of My Mind said:
If the FCC does decide to officially sanction it, would be nice if they allowed it to go on 87.70 so it would work properly on a standard digital FM tuner. WNYZ-LP always had a lot of hash-like distortion on my digitally tuned radios
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It's just not a practical application either from a technical perspective. In spite of whatever RF filter manufacturer mask filter, it's unlikely to keep one digital carrier out of another that close.
 
kfbkfb said:
IIRC, the Franken FMs are allowed to use the FM broadcast format (75kHz, 19kHz stereo pilot) instead of the NTSC FM format (25kHz, 15.734kHz stereo pilot, dBx NR),
Click to expand...
Has that ever been officially sanctioned by the FCC? Sure, that's what almost all of them did, but since they're licensed as TV stations, they were always supposed to conform to the 25 kHz deviation analog TV audio specification.
 
kfbkfb said:
IIRC, the Franken FMs are allowed to use the FM broadcast format (75kHz, 19kHz stereo pilot) instead of the NTSC FM format (25kHz, 15.734kHz stereo pilot, dBx NR), may as well go all the way and let the Franken FMs use 87.7MHz as the center frequency.

NTSC TVs may provide distorted sound from Franken FMs and also wouldn't provide stereo, so compatibility with legacy NTSC audio isn't much of an issue.
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One thing comes to mind:
 
Kelly A said:
One thing comes to mind:
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Lucky me - I actually saw this SNL ep live in late 1986 while planning to go see ST4 at a THX theater (a lot of good this did, WS goes to multiple conventions/year now)

https://twitter.com/WilliamShatner (as a good Lost in Space fan, I follow WS)


Two places I've lived have had NTSC ch 6, in another post, I mentioned routing the sound from the NBC broadcast of the movie Earthquake to my smaller Advent speakers to try to hear the rumble (not very successful, my portable radio was too far from the WOC-TV transmitter).

In the other case, KMOS-TV was an early convert to NTSC BTSC/MTS stereo, which my new (1987-04) VHS HiFi VCR was able to decode.


Kirk Bayne
 
kfbkfb said:
Has anyone asked the FCC why they think 87.75MHz is useful with digital FM tuners?


Kirk Bayne
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Back in the analog days, I never had any issues with 87.75 audio when I set my digital tuner to 87.7 (and every car FM radio I've owned since 1983 had/has one). The 25 kHz deviation of NTSC audio was still well within the 200 kHz channel width. Volume was weak, but there was no distortion whatsoever.

I don't live in an area with "Franken FMs,", but I don't understand why digital video and analog audio couldn't coexist if spaced far enough apart within the channel. I'm not familiar with the ATSC 3.0 spectrum mask, so is it too wide to accommodate such things?
 
Wouldn’t a lot of these owners running a tv channel just to get on a crappy dial position do better buying a cheap AM nobody wants and trying to get a translator for it? Better dial position and invest a lot in streaming.

Very few people scanning the dial are going below 92 unless they know there’s something they want (such as a religious station or NPR). How many people are going to 87.7? This seems like a loophole that should have been addressed ages ago.

Side note, how far do the Franken FM’s normally get out? In larger metros like Chicago (probably the most popular application of this) are they able to provide semi full market coverage comparable to a full market class B FM?
 
101tm said:
Wouldn’t a lot of these owners running a TV channel just to get on a crappy dial position do better buying a cheap AM nobody wants and trying to get a translator for it? Better dial position and invest a lot in streaming.

Very few people scanning the dial are going below 92 unless they know there’s something they want (such as a religious station or NPR). How many people are going to 87.7? This seems like a loophole that should have been addressed ages ago.

Side note, how far do the Franken FM’s normally get out? In larger metros like Chicago (probably the most popular application of this) are they able to provide semi full market coverage comparable to a full market class B FM?
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Not to mention that some car radios don’t even go down to 87.7. I remember renting a Ford Explorer in Chicago several years back, excited to finally hear ME- TV FM (since it wasn’t being streamed), only to have a car radio that stopped at 87.9. There was no way to tune to 87.7 (or 87.8 for that matter). Whoops!
 
101tm said:
Wouldn’t a lot of these owners running a TV channel just to get on a crappy dial position do better buying a cheap AM nobody wants and trying to get a translator for it? Better dial position and invest a lot in streaming.
Click to expand...
That's a possibility, and some people do it. However, translators are limited to 250 watts, and AMs can still be prohibitively expensive. On the other side, though, a low-powered AM would travel far.
101tm said:
Very few people scanning the dial are going below 92 unless they know there’s something they want (such as a religious station or NPR). How many people are going to 87.7? This seems like a loophole that should have been addressed ages ago.
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Advertising and word of mouth, most likely. I don't usually see the 87.7ers in the Nielsen's, (mainly because they can't afford to apply for ratings), but probably about 2-4% of a given population would be on 87.7FM.
101tm said:
Side note, how far do the Franken FM’s normally get out?
Click to expand...
KXDP-LP Denver is 3,000 watts, and it often makes the trip to Cheyenne on the FM side (97 miles away).
101tm said:
In larger metros like Chicago (probably the most popular application of this) are they able to provide semi full market coverage comparable to a full market class B FM?
Click to expand...
I don't know much about Chicago.
 
ZantennaG1 said:
Advertising and word of mouth, most likely. I don't usually see the 87.7ers in the Nielsen's, (mainly because they can't afford to apply for ratings), but probably about 2-4% of a given population would be on 87.7FM.
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Please don't create assumed numbers.

KXDP in Denver gets an average of a 0.5 share and a cume of just slightly over 1% of the population.

WRME in Chicago gets an average of a 3 share and a cume of just over 3% of the total population. That is around 400,000 people who have found that out-of-band frequency.

It all depends on the format and the composition of each market. This is a classic case of "if you build it they will come".
 
DavidEduardo said:
Please don't create assumed numbers.

KXDP in Denver gets an average of a 0.5 share and a cume of just slightly over 1% of the population.

WRME in Chicago gets an average of a 3 share and a cume of just over 3% of the total population. That is around 400,000 people who have found that out-of-band frequency.
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I will remember not to do that in the future. On the bright side, I was at least close to the totals you mentioned here.
DavidEduardo said:
This is a classic case of "if you build it they will come".
Click to expand...
I hope that will be true for FM band expansion as well. *Crosses fingers*
 
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