11m Band Activity 05 MAR 2024

[RobRich]

11m DX is hopping this afternoon here. Europe, Mexico, Hawaii, etc. Even UK NFM CB. Airspy HF+D and 31' vertical.

1827z - 27.66125nfm - Music and occasional voice comms


(click to open)

[R4002]

Nice catch re: UK FM CB Channel 7 - that is, 27.66125 MHz FM. 

It seems like channels 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 29, 30, 31, 32, 38, 39 and 40 are the most popular ones, at least from my personal experience.  I've noticed that channels 1 through 9 (so 27.60125 MHz FM to 27.70125 MHz FM) seem to suffer the most as far as SSB QRM goes.  There are others, including channels 16/17, due to a data link system on 27.760 MHz (center frequency).  10-12 kHz wide, with two wide MFSK signals located roughly 4-5 kHz below and 4-5 kHz above the center frequency.  Plus, 27.765MHz is very popular for out of band operation (mostly in Europe)

Pagers on 27.750 MHz, 27.800 MHz, 27.845 MHz, 27.850 MHz, 27.885 MHz, 27.900 MHz and 27.940 MHz also seem to cause some pretty serious QRM when the band is open.

I know UK FM CB Channel 14 is, or was, the base station to base station calling channel or working channel.  DXing on UK FM CB channels 30, 31, 38, 39 and 40 seems to be somewhat popular too.

That is...

27.73125 MHz FM - 27731 FM - UK FM CB Radio Channel 14
27.74125 MHz FM - 27741 FM - UK FM CB Radio Channel 15
27.75125 MHz FM - 27751 FM - UK FM CB Radio Channel 16
27.76125 MHz FM - 27761 FM - UK FM CB Radio Channel 17
27.77125 MHz FM - 27771 FM - UK FM CB Radio Channel 18 - frequent QRM from 27.775 MHz AM or FM
27.78125 MHz FM - 27781 FM - UK FM CB Radio Channel 19 - often getting slammed by taxis on 27.785 MHz AM
27.79125 MHz FM - 27791 FM - UK FM CB Radio Channel 20
27.80125 MHz FM - 27801 FM - UK FM CB Radio Channel 21 - sporadic QRM from 27.8 MHz POCSAG
27.81125 MHz FM - 27811 FM - UK FM CB Radio Channel 22
27.82125 MHz FM - 27821 FM - UK FM CB Radio Channel 23
27.83125 MHz FM - 27831 FM - UK FM CB Radio Channel 24
27.84125 MHz FM - 27841 FM - UK FM CB Radio Channel 25 - QRM from 27.845 MHz / 27.850 MHz POCSAG
27.88125 MHz FM - 27881 FM - UK FM CB Radio Channel 29 - suffers QRM from pager system on 27.885 MHz
27.89125 MHz FM - 27891 FM - UK FM CB Radio Channel 30 - suffers QRM from pager system on 27885
27.90125 MHz FM - 27901 FM - UK FM CB Radio Channel 31 - QRM from 27.9 MHz paging signals
27.91125 MHz FM - 27911 FM - UK FM CB Radio Channel 32 - 27.915 MHz is very popular with US freebanders
27.94125 MHz FM - 27941 FM - UK FM CB Radio Channel 35 - Severe QRM from 27.940 MHz data and POCSAG paging
27.97125 MHz FM - 27971 FM - UK FM CB Radio Channel 38 - QRM from taxi cabs on 27.965 MHz and 27.975 MHz
27.98125 MHz FM - 27981 FM - UK FM CB Radio Channel 39 - 27.980 MHz USB is a popular free band SSB DX freq
27.99125 MHz FM - 27991 FM - UK FM CB Radio Channel 40