SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Busselton Perth Date: 21 October, 2025 T-index: 100 Bearings: 15 195 Distance: 196 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F/1E: Near 90 1 5 10 15 20 25 30 35 40 ** NONE ** UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 6.8 3.9 3.0 AFFF%%. 00 01 7.1 4.3 3.2 BFFF%. 01 02 7.6 4.6 3.4 BFFF%%. 02 03 8.1 4.7 3.5 AFFFF%. . 03 04 8.4 4.8 3.6 AFFFF%. . 04 05 8.5 4.8 3.6 AFFFF%% . 05 06 8.3 4.7 3.5 AFFFF%% . 06 07 7.9 4.5 3.4 BFFF%%. . 07 08 7.7 4.1 3.2 BFFF%%. 08 09 7.5 3.6 2.8 AFFFF%%. 09 10 7.2 2.8 2.3 FFFFF%.. 10 11 6.7 0.6 0.0 FFFFFF%%.. 11 12 6.2 0.6 0.0 FFFFFF%.. 12 13 5.6 0.6 0.0 FFFFF%%. 13 14 5.3 0.6 0.0 FFFFF%.. 14 15 5.1 0.6 0.0 FFFFF%. 15 16 4.8 0.6 0.0 FFFF%%. 16 17 4.6 0.6 0.0 FFFF%.. 17 18 4.5 0.6 0.0 FFFF%. 18 19 4.2 0.6 0.0 FFFF%. 19 20 4.0 0.6 0.0 FFF%%. 20 21 4.1 0.6 0.0 FFFF%. 21 22 5.1 1.8 1.6 AFFF%. 22 23 6.2 3.2 2.6 AFFF%. 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) 21-Oct-2025 BoM Space Weather Services, Sydney Australia +61-2-9213-8000