SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Albany Perth Date: 21 October, 2025 T-index: 100 Bearings: 331 152 Distance: 386 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 51-61 1E 24 1 5 10 15 20 25 30 35 40 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 7.2 5.7 3.3 BBFF%.. 00 01 7.6 6.3 3.6 ABBF%%. 01 02 8.0 6.7 3.8 ABBF%%. . 02 03 8.6 6.9 3.9 ABBFF%% . 03 04 8.9 7.0 3.9 ABBBF%% .. 04 05 9.1 7.0 3.9 ABBBFF% .. 05 06 8.8 6.8 3.8 ABBFF%% .. 06 07 8.4 6.5 3.7 ABBFF%% . 07 08 8.2 6.0 3.4 BBBFF%. . 08 09 8.0 5.3 3.1 BBFF%%. . 09 10 7.6 4.0 2.5 ABFFF%%. . 10 11 7.0 0.9 0.0 FFFFFF%%.. 11 12 6.5 0.9 0.0 FFFFFF%%. 12 13 5.8 0.9 0.0 FFFFF%%. 13 14 5.5 0.9 0.0 FFFFF%.. 14 15 5.3 0.9 0.0 FFFFF%.. 15 16 5.0 0.9 0.0 FFFF%%. 16 17 4.8 0.9 0.0 FFFF%%. 17 18 4.6 0.9 0.0 FFFF%.. 18 19 4.3 0.9 0.0 FFFF%. 19 20 4.2 0.9 0.0 FFFF%. 20 21 4.2 0.9 0.0 FFFF%. 21 22 5.4 3.0 1.9 ABFF%. 22 23 6.5 4.8 2.9 ABFF%.. 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