RE: AM radio is NOT dead!!

[Dan Strassberg <dan.strassberg@worldnet.att.net>]

At 03:29 PM 6/11/97 +0000, you wrote:
>
>What is a NRSC filter?  (he asked, non-technically)
>
NRSC stands for National Radio Standards Committee. The NRSC specified
sideband filters for AM stations that, I believe, all US AMs are supposed to
be using. The filters attenuate the sidebands very sharply beyond about 8 or
9 kHz from the carrier. The objective was to allow AM stations to repeatedly
hit 100% modulation on negative peaks (125% on positive peaks) without
generating sidebands that would screw up reception of adjacent-channel
stations, except maybe for stations on the first adjacent channels. The
other objective was not to reduce the bandwidth excessively so that the
programming would still sound acceptable. Since most AM radios nowadays
don't even have 5-kHz audio bandwidth, rolling off the sidebands beginning
about 8.5 kHz from the carrier should not produce a noticeable reduction in
treble to most listeners.

- -------------------------------
Dan Strassberg (Note: Address is CASE SENSITIVE!)
ALL _LOWER_ CASE!!!--> dan.strassberg@worldnet.att.net
(617) 558-4205; Fax (617) 928-4205

------------------------------