SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 23 October, 2026 T-index: 40 Bearings: 201 24 Distance: 1680 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 12-18 1E 2 1 5 10 15 20 25 30 35 40 2F 28-36 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 13.4 14.4 8.1 ASSSXM BBBP%%... 8.2 9.5 4.7 00 01 13.6 15.7 8.8 SSSXX BBBPP%... 8.3 10.4 5.1 01 02 14.1 16.7 9.2 SSSXX BBBBPP%... 8.6 11.0 5.4 02 03 14.8 17.2 9.4 ASSXX XBBBPPP%.. . 9.0 11.4 5.5 03 04 15.4 17.4 9.5 ASSSX XBBBBPP%.. .. 9.4 11.6 5.5 04 05 15.6 17.2 9.4 ASSSX XMBBBPP%%. .. 9.6 11.5 5.5 05 06 15.0 16.7 9.2 SSSSX XBBBPP%%.. .. 9.5 11.2 5.3 06 07 14.5 15.9 8.8 SSSXX MBBBP%%%.. . 9.1 10.6 5.1 07 08 13.9 14.5 8.2 ASSSXM MBBP%%%... . 8.8 9.7 4.8 08 09 14.1 12.5 7.2 SSSXMM MBFF%%%... . 8.8 8.2 4.3 09 10 12.4 8.6 5.3 SSMMMMM FF%%%%.... . 8.4 5.0 3.3 10 11 10.6 2.0 0.0 XMMMMMMMMM %%%%%..... . 7.4 1.4 0.0 11 12 9.2 2.0 0.0 XMMMMMMMF% %%%..... 6.6 1.4 0.0 12 13 8.4 2.0 0.0 XMMMMMMM%% %%.... 6.0 1.4 0.0 13 14 8.3 2.0 0.0 XMMMMMMF%% %.... 5.8 1.4 0.0 14 15 8.6 2.0 0.0 XMMMMMMF%% %.... 5.8 1.4 0.0 15 16 8.5 2.0 0.0 XMMMMMMF%% %... 5.7 1.4 0.0 16 17 8.0 2.0 0.0 XMMMMMM%%% .... 5.5 1.4 0.0 17 18 7.0 2.0 0.0 XMMMMM%%%. .. 5.2 1.4 0.0 18 19 6.3 2.0 0.0 XMMMMM%%.. . 4.7 1.4 0.0 19 20 5.9 2.0 0.0 XMMMM%%%.. . 4.6 1.4 0.0 20 21 6.5 2.0 0.0 XMMMMM%%.. .. 4.9 1.4 0.0 21 22 9.7 7.9 4.9 ASMMMMF% %%.... 6.5 4.9 3.0 22 23 12.6 12.2 7.1 SSSMMB BB%%%... 7.8 8.0 4.2 23 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT =============================================================================== |. USABLE LESS THAN 50% OF DAYS |% USABLE 50% TO 90% OF DAYS | |B BOTH E and F MODES 90% OF DAYS |M MIXED FIRST AND SECOND F MODES | |F FIRST F MODE ONLY |E E-LAYER PROPAGATION |P 90% E and 50-90% F | |S SECOND MODES ONLY |A HIGH ABSORPTION |X COMPLEX MODES | (c) 23-Oct-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000