SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Albany Perth Date: 4 May, 2026 T-index: 85 Bearings: 331 152 Distance: 386 km First Mode |--------F r e q u e n c y (MHz)---------| Second Mode 1F 51-55 1E 24 1 5 10 15 20 25 30 35 40 UT OWF EMUF ALF |...|....| ....|....| ....|....| ....|....| OWF EMUF ALF UT 00 7.7 4.5 2.6 ABFFF%%. 00 01 8.8 5.4 3.1 BBFFF%% .. 01 02 9.4 6.0 3.3 BBBFFF% %. 02 03 9.6 6.3 3.4 BBBFFF% %.. 03 04 9.6 6.4 3.5 ABBFFF% %.. 04 05 9.7 6.3 3.5 ABBFFF% %.. 05 06 9.7 6.1 3.4 BBBFFF% %.. 06 07 9.6 5.7 3.2 BBFFFF% %.. 07 08 9.3 5.0 2.8 ABBFFFF% %. 08 09 8.6 3.6 2.2 BFFFFF%% .. 09 10 7.1 0.9 0.0 FFFFFFF%.. 10 11 5.5 0.9 0.0 FFFFF%%.. 11 12 4.7 0.9 0.0 FFFF%%. 12 13 4.2 0.9 0.0 FFFF%. 13 14 4.0 0.9 0.0 FFF%%. 14 15 3.9 0.9 0.0 FFF%.. 15 16 3.9 0.9 0.0 FFF%.. 16 17 3.8 0.9 0.0 FFF%.. 17 18 3.6 0.9 0.0 FFF%.. 18 19 3.6 0.9 0.0 FFF%.. 19 20 3.5 0.9 0.0 FFF%.. 20 21 3.2 0.9 0.0 FFF%. 21 22 3.4 0.9 0.0 FFF%. 22 23 5.5 1.9 1.3 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) 4-May-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000