[BC] What ever happen(ed) to AMAX

[Kevin Tekel]

John wrote:
> Am I correct in my recalling that AMAX was originally done with input
> from NAB but without NRSC input?  I seem to recall that some group at
> NRSC were working on a standard for putting data (SCA-style) in the AM
> fringes at the time and AMAX killed that (just as it would IBOC now).
> I think that's also why there's an NAB logo on the first unit released
> by Denon... I recall hearing all this from someone that was working on
> the data standard who was unhappy to say the least.

"AMAX" was the consumer marketing name for the NRSC-3 AM receiver
recommendations.  It was designed to match the NRSC-1 and NRSC-2 bandwidth
and pre-emphasis standards for AM broadcasters.  I believe the NRSC-4
standard is for FM RDS and NRSC-5 is for IBOC.  You can find the technical
details on all of these standards on the NRSC's web site.

AMAX has nothing to do with telemetry or other subcarriers transmitted by
AM stations.  It is a receiver standard.  Nonetheless, I believe it is
still legal to transmit AM telemetry, and telemetry is even compatible
with C-Quam AM Stereo, as long as you use a high-pass filter in the L-R
channel (this filter is built into the Optimod 9100 audio processor).  In
fact, about 6 or 7 years ago, AM RDS was developed, and it too is
compatible with
C-Quam AM Stereo, but it never reached consideration for FCC approval.


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com