SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Busselton Perth Date: 17 September, 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 7.4 3.6 2.8 AFFFF%. 00 01 8.0 4.1 3.1 BFFF%%. 01 02 8.5 4.4 3.3 BFFFF%. . 02 03 8.8 4.6 3.4 BFFFF%% . 03 04 8.9 4.7 3.5 AFFFF%% . 04 05 8.9 4.6 3.4 BFFFF%% .. 05 06 8.5 4.5 3.4 BFFFF%% . 06 07 8.2 4.3 3.2 BFFFF%. . 07 08 8.1 3.9 3.0 AFFFFF%. . 08 09 8.0 3.3 2.6 AFFFF%%. 09 10 7.4 1.9 1.6 AFFFFF%%. 10 11 6.5 0.6 0.0 FFFFFF%%. 11 12 5.7 0.6 0.0 FFFFF%%. 12 13 5.2 0.6 0.0 FFFFF%. 13 14 4.8 0.6 0.0 FFFF%%. 14 15 4.6 0.6 0.0 FFFF%.. 15 16 4.4 0.6 0.0 FFFF%. 16 17 4.2 0.6 0.0 FFFF%. 17 18 4.1 0.6 0.0 FFFF%. 18 19 3.9 0.6 0.0 FFF%.. 19 20 3.7 0.6 0.0 FFF%. 20 21 3.6 0.6 0.0 FFF%. 21 22 4.2 0.6 0.0 FFFF%. 22 23 6.2 2.7 2.2 FFFF%. 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) 17-Sep-2025 BoM Space Weather Services, Sydney Australia +61-2-9213-8000