The Finch Formerly Known As Gold

11 October 2004

Wish I'd thought of this

It's a step beyond serendipity: the ability to claim credit for an innovation that requires you to do nothing at all.

Tulsa's KOTV, channel 6, is now promoting its Online Audio at its Web site, and you don't even need to be online to listen to it: just tune your FM radio to 87.7 MHz.

Under FCC rules, an analog TV channel covers a bandwidth of 6 MHz; channel 6 runs from 82 to 88 MHz. The color subcarrier is generally located 1.25 MHz from the bottom of the channel, or at 83.25 MHz.

TV video is AM. TV audio, however, is FM, and the FM subcarrier is located 4.5 MHz above the video subcarrier in all TV channels. On channel 6 in Tulsa, or indeed channel 6 anywhere in the US or Canada, this means 87.75 MHz. (Actually, some stations, including KOTV, are required by the FCC to offset their subcarriers by 0.01 MHz, so the actual FM audio from KOTV is at 87.76 MHz.) This signal is well within the reach of any FM receiver within transmitter range which can be tuned to approximately 87.7, and KOTV didn't have to do anything extra to provide it; it's a by-product of the way the spectrum is assigned. Any station on channel 6 should be similarly accessible.

On a hunch, I spot-checked three stations I knew to be on channel 6 — in Corpus Christi, Miami and Philadelphia — and none of them was promoting an FM-audio feed on the front page of its Web site.

Posted at 6:26 AM to Overmodulation


It's not a featue, it's a bug. Been a long time since I've heard anyone discussing the frequency-modulated NTSC aural subcarrier.

Check WJAC-TV, Channel 6 from Johnstown Penna.

Just another laid-off cable geek

Posted by: Fûz at 10:26 AM on 11 October 2004

I worked at 42nd and Treadmill for a week back in August and was confronted by a man who seemed as unhappy with the world as I am with the fact that my grandmother just won't die and finally leave me all of her money. I believe his name was Charlie (but John also comes to mind for some reason) and he wrote pieces on the irony and stupidity of individuals and their idea's. I was wondering if you are the same guy, since I was just scanning the net and found this site. I liked his personal synopsis on the Victoria Secret's million dollar underware, and some of the other titles seemed interesting. Anyhow, please let me know if I have the right site since I'm unable to find the screen with the actual titles listed.

Amanda Miller

Posted by: Amanda at 10:50 PM on 17 October 2004

A real bastard, that guy. (Even though I know for a fact that his parents were married. To each other, even.)

The VS piece is here.

Posted by: CGHill at 12:01 PM on 18 October 2004