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tonyc69
26th Aug 2009, 04:09
Hi guys. Based on your experiences, what set of HF freqs would be most suitable for voice communication use in equatorial region. The HF freq of 5728Khz we currently use varies too much in performence; today it might be Strength 5, the next day Strength 1 :yuk:.... Would be nice i think to have 1 freq for day time use & another for late evening.

Thxs for the help.

Regards...

Ex FSO GRIFFO
26th Aug 2009, 05:25
G'Day Tony,

Depending on your distance from the TX/Rx site, and time of day, you might try a 6mhz -morning and 8mhz - afternoon for daytime use, and maybe a 3 or 4mhz for early morning & night time use.

6 and 8 seem to be good for 'most' day ranges whilst when the ionispheric 'layers' condense of a night time, the lower freqs will be best.
However, if you are oceanic, (long range) you will probably have to go to the higher freqs.
All freqs being subject to the afternoon 'Cb' interference of course....

Fairly 'general' I know, but hope this may be of use to you.

If you are able to contact your ATS provider, they may be able to provide you with an 'Ionispheric Prediction Service' for HF use for your area of operation.
These freqs are calculated from charts, and are provided for your time/area of operation. They are not 'foolproof', but are a good guide.

Cheers:ok:

tonyc69
27th Aug 2009, 04:17
Thxs Griffo for the info. Will try out & monitor the freqs. I also managed to 'dick out' some info from the internet on the freqs used by South East Asia ATC (as below), might serve as a guilde line as well.
SEA-1

3470
5670
6556
10066
13318
17907
Bali, Bangkok, Colombo, Calcutta, Dhaka, Guangzhou, Jakarta, Kathmandu, Kuala Lumpur, Kunming, Madras, Male, Singapore, Yangon

SEA-2

3485
5649
5655
8942
11396
13309
17907
Bali, Bangkok, Guangzhou, Hanoi, Ho Chi Minh, Hong Kong, Jakarta, Kuala Lumpur, Kota Kinabalu, Manila, Seoul, Singapore, Tokyo, Vientiane

SEA-3

3470
5733
6556
10066
11396
13318
17907
Bali, Cocos Islands, Jakarta, Male, Perth, Singapore, Ujung Pandang

Will post soonest on detection of better freqs set.
Regards ;)