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Old December 12th 15, 04:30 PM posted to rec.radio.broadcasting
hwh[_2_] hwh[_2_] is offline
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First recorded activity by RadioBanter: Sep 2010
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Default AM Tuning steps (9 vs. 10khz)

On 11/12/15 19:19, wrote:
On Wednesday, January 22, 2003 at 9:45:02 AM UTC+11, Mel3k wrote:
I'm not sure if this has been asked before, but why does AM radio in
Europe/Asia tune in 9khz steps while North American AM goes by steps
of 10khz? Also, why did some countries like Australia switch from
10khz to 9khz steps some years back?

Thanks for your insights


If you go back to the history of AM radio, the entire world was using 10 kH
z on AM, which was back in the days when the radios did not have digital di
splays on them.


Europe used 9 kHz spacing for most of the band, and 8 kHz for the top
end. In 1978 the switch was made to 9 kHz only, and in frequencies
dividable by 9. So there is no relation to the invention of digital
displays. The US not only has 10 kHz spacing, stations used up to 10 kHz
in their modulation while European stations used only 4.5 kHz. So in the
US 'neighboring' stations had to be separated geographically.

gr, hwh