Re: AM spacing

[Dan.Strassberg@att.net]

The only explanation I know is, "that's just the way it is."

Maybe 20 years ago an abortive attempt was made to bring the whole world into 
line by instituting 9-kHz spacing in the Western Hemisphere. Various arguments 
were put forth. Of those, the one I found most compelling was that. even then, 
a small number of car radios (as well as some stand-alone radios) would have to 
be scrapped because they were designed to tune only in 10-kHz increments. Other 
arguments included the the likely need for more bandwidth, not less, when a 
digital-audio-broadcast system was developed. Both arguments were valid.

I've never heard AM in a crowded area with 9-kHz spacing, so I can't comment on 
a difference in the sound, but any such difference would clearly result from 
narrower audio bandwidth designed into the receivers in an attempt to suppress 
the 9-kHz intercarrier beat note, which would obviously be more noticeable and 
more annoying then a 10-kHz beat note. My guess is that AM receivers of 
acceptable quality designed for 9-kHz spacing would be somewhat more expensive 
than receivers designed for 10-kHz spacing.
--
dan.strassberg@att.net
617-558-4205
eFax 707-215-6367
> Is there a reasonably simple explanation as to why AM spacing is 10 kHz here
> and 9 kHz in other parts of the world?  Is there a difference in how the
> station covers or even "sounds?"
> 
> Bill O'Neill
>