SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Broome Perth Date: 28 February, 2026 T-index: 90 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 29-37 2E 10 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 14.9 15.1 8.8 SSSXM MBBBP%%%.. . 9.2 9.9 5.2 00 01 16.1 16.6 9.5 ASSSX MMBBBB%%%. .. 9.7 11.0 5.6 01 02 16.7 17.6 10.0 ASSSX XMBBBBP%%% ... 10.2 11.7 5.8 02 03 17.7 18.2 10.3 ASSSS XXBBBBBP%% .... 10.6 12.1 6.0 03 04 17.9 18.4 10.4 ASSSS XXMBBBBP%% .... 10.8 12.2 6.0 04 05 18.3 18.2 10.3 ASSSS XXMBBBBB%% %.... 11.0 12.1 6.0 05 06 17.9 17.7 10.0 ASSSX XMMBBBB%%% %.... 10.9 11.8 5.8 06 07 17.4 16.7 9.6 ASSSX XMMBBBF%%% %..... 10.6 11.2 5.6 07 08 16.9 15.3 8.9 SSSXX MMMBBF%%%% %.... 10.4 10.2 5.2 08 09 16.3 13.0 7.8 ASSXMM MMBFFF%%%% .... 10.1 8.5 4.6 09 10 14.6 8.3 5.4 SSMMMMM MMFF%%%%%. .... 9.4 4.7 3.4 10 11 12.8 2.4 0.0 XMMMMMMMMM MF%%%%%... ... 8.6 1.6 0.0 11 12 11.3 2.4 0.0 XMMMMMMMMM F%%%%..... 7.8 1.6 0.0 12 13 10.6 2.4 0.0 XMMMMMMMMF %%%%..... 7.2 1.6 0.0 13 14 10.0 2.4 0.0 XMMMMMMMF% %%%.... 6.7 1.6 0.0 14 15 10.1 2.4 0.0 XMMMMMMMFF %%%.... 6.6 1.6 0.0 15 16 10.1 2.4 0.0 XMMMMMMMFF %%%.... 6.5 1.6 0.0 16 17 9.9 2.4 0.0 XMMMMMMMF% %%.... 6.4 1.6 0.0 17 18 8.8 2.4 0.0 XMMMMMMF%% %..... 6.1 1.6 0.0 18 19 7.9 2.4 0.0 XMMMMMM%%% %.... 5.9 1.6 0.0 19 20 6.9 2.4 0.0 XMMMMM%%%. ... 5.2 1.6 0.0 20 21 6.5 2.4 0.0 XMMMMM%%%. .. 5.0 1.6 0.0 21 22 9.0 7.3 4.8 ASMMMF%% %... 6.0 4.2 3.0 22 23 13.4 12.7 7.6 ASSXMM BBF%%%... 8.0 8.3 4.5 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) 28-Feb-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000