Re: First Reference to Digital AM Radio I've Seen So Far

["Dan Strassberg" <Dan.Strassberg@att.net>]

WCLV had its back to the wall financially. This was obviously a last-ditch
move to preserve commercial classical radio in some form in northeast Ohio.
For Salem, it was a no-brainer. Salem now owns two of the three 50 kW AM
signals in Cleveland (850 and 1220) and has no real use for 1420 anymore--or
its other Cleveland AM for that matter (1300?). But the idea that there will
ever be useful digital stereo on the AM band is a fairy tale. Broadcasters
are technically naive and readily engage in the kind of wishful thinking
that makes them easy prey for technological snake-oil salesmen. See for
yourself; plug the numbers into Shannon's equation (C/B = log2 (1+S/N),
where C=channel capacity in bps, B is bandwidth in Hz, and S/N is the ratio
of signal power to noise power in the bandwidth of interest). Digital stereo
broadcasts on AM will have such incredibly limited range that the stations
that can use the system will probably be limited to the 50 kW AMs (if any)
in North and South Dakota. Out there, the soil conductivity is good enough
and the adjacent-channel interference is low enough (during the day, anyhow)
that usable coverage of the digital stereo broadcasts might actually extend
all the way from one side of Bismarck to the other. You think we have
ridiculous situations in New England with the flea-power that many former
daytimers are running at night. (I know, with CBL dark, you can get a nice
signal from WJIB at night a few miles outside of Route 128, but that's
because there is no co-channel interference at the moment--unless of course
CHWO has started testing.) Using digital stereo, your typical 5-kW New
England AM won't do as well during the daytime as WJIB did at night when CBL
was booming in. You'll be lucky to get a usable signal if you and your
digital radio are standing on the station's ground system. I hate to burst
WCLV's bubble, but digital stereo on AM will not be their salvation. WCLV
has (or used to have) a pretty nice Web site, though. If they want to stay
alive, they'd better firgure out how to make money with that.

--

Dan Strassberg, dan.strassberg@worldnet.att.net
Phone: 1-617-558-4205, eFax: 1-707-215-6367

-----Original Message-----
From: Bob Nelson...WMWM <bobonradio@yahoo.com>
To: boston-radio-interest@bostonradio.org
<boston-radio-interest@bostonradio.org>
Date: Thursday, November 02, 2000 8:53 PM
Subject: Re: First Reference to Digital AM Radio I've Seen So Far


>I just heard about this from my friend Tim Davisson
>in Ohio, who occasionally posts to this list. I think
>he said religious broadcaster Salem is buying WCLV
>and the classical station will wind up eventually on
>AM 1420 and FM 104.9, as you say, but the FM will
>indeed be very weak. (What's Class A, 3,000 watts?)
>