SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Bunbury Perth Date: 1 December, 2025 T-index: 90 Bearings: 8 188 Distance: 155 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 5.6 3.7 3.0 AFF%%. 00 01 5.9 4.0 3.2 BF%%.. 01 02 6.3 4.2 3.3 BFF%%. 02 03 6.8 4.4 3.4 BFF%%.. 03 04 7.0 4.4 3.4 BFF%%.. 04 05 7.1 4.4 3.4 BFFF%.. 05 06 6.9 4.3 3.4 BFF%%.. 06 07 6.8 4.2 3.3 BFF%%.. 07 08 6.7 3.9 3.1 FFF%%.. 08 09 6.6 3.5 2.8 AFFF%%. 09 10 6.4 3.0 2.5 AFFF%%. 10 11 6.2 1.8 1.6 AFFFF%.. 11 12 5.9 0.5 0.0 FFFFF%%.. 12 13 5.5 0.5 0.0 FFFFF%%. 13 14 5.2 0.5 0.0 FFFFF%.. 14 15 5.1 0.5 0.0 FFFFF%. 15 16 5.0 0.5 0.0 FFFF%%. 16 17 4.7 0.5 0.0 FFFF%.. 17 18 4.5 0.5 0.0 FFFF%.. 18 19 4.3 0.5 0.0 FFFF%. 19 20 4.1 0.5 0.0 FFFF%. 20 21 4.3 0.5 0.0 FFFF%. 21 22 4.8 2.5 2.1 FF%%. 22 23 5.1 3.2 2.6 AFF%.. 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) 1-Dec-2025 BoM Space Weather Services, Sydney Australia +61-2-9213-8000