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Richard Westcott
January 18th, 2009, 06:13
I have a small handheld scanner which I occasionally use for VHF and UHF listing, but I am thinking of buying a desktop scanner which also covers HF.

I have used liveatc.net a number of times but their HF coverage is usually down.

Has anyone scanned HF before, I was wondering how busy and interesting it was?

Thanks

falcon409
January 18th, 2009, 06:54
I also use live ATC from time to time and find that outside of the major hubs most of the listed airports are usually inactive more often than not. Never considered a scanner really.

srgalahad
January 18th, 2009, 08:14
HF?? It's hit or miss whether you'll hear much at all.

The standard frequency spectrums for aviation are
VHF 108 -117.975MHz (navaids -vor/ILS)
VHF 118.000-137MHz (ATC/FSS comm)
UHF in the range of 215-387MHz (Military comm, UHF nav -Tacan) most civilian ATC units may only have one or two UHF frequencies available to accomodate mil. flights.

HF was common until the 50's but as VHF came along it was far superior for direct communication. When I got into ATC in the 70's HF was mostly gone from everywhere but FSS who relayed position reports to ATC.

The HF bands are not used for 'normal communication' except over long distances - the far arctic and oceanic routes for example that are beyond VHF line-of-sight range. As HF is atmospheric-dependent it's use is unpredictable and sometimes awkward. More and more countries are installing VHF repeaters in remote areas to reduce the need for HF. Most of the traffic you'll hear will likely be aircraft position reports transiting the Oceanic corridors, or company communications (Flight Ops for example- but even less of that now) A frequency list can be found here: http://www.grove-ent.com/mtmwara.html

Because of the atmospheric issues (skip, etc.) you can get some "wierd" stuff - like hearing one half of a communication from a station hundreds or even thousands of miles away, and not be able to hear the other side which may be close-by. Also a given frequency may work for a while and as soon as the aircraft has moved that freq. is lost. The quality basically is poor because of the lower frequency range. Fun to listen to occasionally, but I wouldn't spend the money to listen.

Rob

Richard Westcott
January 18th, 2009, 09:36
Thanks Falcon and Rob, you have both answered my question, I think I will save my money!

All the best