ILS channels

[Cron]

40 channels but 20 frequencies? What's the realtionship please?

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London Tower this is Skyflash...

[avoman]

Nope. 40 channels and 40 frequencies, if we're talking localiser, which is the frequency published, and selected onboard. Frequencies are in the band 108.10 to 111.95 MHz, odd decimals and subsequent 50 kHz. eg 108.10,108.15,108.30,108.35 etc.
Additionally there is a paired glideslope frequency for each of the above, from 329.15 to 335 MHz, automatically tuned.
Indeed to complete the ILS system there is Marker! always 75 MHz.
I wonder if you are thinking of the DME system? That has 200 channels but only 100 frequencies. But that's another story, described on this forum I think about a month ago.

[Cron]

Got it, thanks

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London Tower this is Skyflash...

[avoman]

the DME story is on a thread called DME Frequencies on Tech Log 23-10-00

[Cron]

Sorry to be thick .. how do I get to it? Tried honest

[avoman]

show topics for last 45 days, page 6

[Cron]

Got it, thank you

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London Tower this is Skyflash...