All good radio amateurs are constrained to using certain bands of frequencies. Within each band, voluntary band plans assign "emergency priority" frequencies that RAYNET uses.

Keighley's preferred choice of operating frequencies are below but may be changed for operational reasons

Leeds RAYNET net is on 144.625 MHz on Monday at 20:00

National RAYNET Frequencies

80 meters

3.663 MHz SSB National co-ordination during emergencies and the 80 meter RAYNET News every Sunday at 08:30 local time

40 meters

7.090 MHz SSB National co-ordination during emergencies

6 meters

51.210 NBFM 51.950 NBFM 51.960 NBFM 51.970 NBFM 51.980 NBFM 51.990 NBFM  A large number of Internet Gateways use 51.950, effectively making it unusable for RAYNET in many areas

Keighley RAYNET running one of the talk-through on the Ripon "100"

4 meters

Leeds RAYNET's 3 Peaks Race

70.3500 NBFM 70.3750 NBFM 70.4000 NBFM 70.3500 is listed for digital mode use as well as emergency communications

2 meters

144.260  USB 144.625 NBFM 144.650 NBFM 144.675 NBFM 144.775 NBFM 144.800 NBFM 144.825 NBFM 145.200 NBFM 145.225 NBFM 144.800 NBFM - Data communication (shared with APRS) 145.200 Emergency Communications Groups utilising this frequency should take steps to avoid interference to ISS operations    in non-emergency situations.

G0SCV on a checkpoint for Keighley RAYNET

There is still some residual packet operation on 144.650 and the French band  plan still uses the 144.6xx part of the band for packet. Frequencies should be chosen with care, particularly when using talk-through units

70 centimetres

Keighley RAYNET running talk-through for Leeds RAYNET

433.700 NBFM 433.725 NBFM 433.750 NBFM 433.775 NBFM 433.700 is listed as IARU Region 1 packet as well as emergency communications. 438.400 - 430.800 NBFM, Voice repeater Base TX on 438.400 mobiles TX on 430.800 (-7.6MHz repeater shift. This has been chosen so that usage is compatible with most modern radios which have a wide negative shift available as standard). This is a 7.6MHz split repeater pair in the 70cm "wide" repeater section. Further information about this portion of the band can be found on the RSGB's Repeater Management Committee website. 432.775 - 434.375 NBFM, Voice repeater Base TX on 432, mobiles TX on 434 (standard +1.6MHz repeater shift)

The International Space Station

As a result of feedback from last week's GB2RS news item regarding the use of 145.200MHz and 145.800MHz by the International Space Station, the RSGB Spectrum Forum feels some clarification is needed and the following joint statement has been agreed with the IARU Region 1 Satellite Co-coordinator, the RSGB's Radio Communications Voluntary Services and The Radio Amateurs' Emergency Network Spectrum Forum members.

Although both the frequencies 145.200MHz and 145.800MHz have historically been used for domestic UK emergency communications, it was agreed at the IARU Region 1 Conference in 1996 to allocate 145.200MHz as an FM uplink channel with 145.800MHz serving as the downlink side of the pair. This particular frequency pair, which applies only for Region 1, had earlier been agreed by IARU internationally after discussions with NASA and AMSAT.

The likelihood of an active ISS pass taking place at the same time as bona fide UK emergency communications operations using 145.200MHz and / or 145.800MHz is considered low and due to the nature of circumstances would only be for a brief period in any case. In addition, the UK amateur radio emergency communications community has for many years discouraged the use of 145.800MHz as far as possible, and even then only using low power and vertical polarisation, due in any case to its proximity to the satellite sector.

UK terrestrial stations are therefore again requested to check for activity from ISS before transmitting. Details of the ISS orbits can be found on the Internet.