In article ,
wrote:
They used AM sound. The sound IF was at 30odd megs and was wide
bandwidth, and did not restrict the audio bandwdth. AM radios have an IF
of about 0.45 MHz, and just that difference will reduce bandwidth on MF
radio (as compared to 405 TV sound by a factor of about 75.

In practice most sets did. When BBC 2 started with FM sound it added an
extra octave or so at the top end via the average receiver.

--
*When it rains, why don't sheep shrink? *

Dave Plowman London SW
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