SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Albany Perth Date: 25 July, 2026 T-index: 75 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 6.3 4.2 2.4 BBFF%. 00 01 7.3 5.2 2.9 ABBFF%.. 01 02 7.7 5.8 3.2 BBFF%%. 02 03 7.9 6.1 3.3 BBBF%%. . 03 04 8.0 6.2 3.4 BBBF%%. . 04 05 8.0 6.1 3.3 BBBF%%. . 05 06 8.1 5.9 3.2 BBFFF%. . 06 07 8.1 5.5 3.0 ABBFFF%. . 07 08 7.9 4.7 2.7 ABFFF%%. . 08 09 7.2 3.0 1.9 ABFFFF%.. 09 10 5.8 0.9 0.0 FFFFF%%.. 10 11 4.4 0.9 0.0 FFFF%.. 11 12 3.8 0.9 0.0 FFF%.. 12 13 3.4 0.9 0.0 FFF%.. 13 14 3.2 0.9 0.0 FFF%. 14 15 3.2 0.9 0.0 FFF%. 15 16 3.1 0.9 0.0 FFF%. 16 17 3.1 0.9 0.0 FFF%. 17 18 3.1 0.9 0.0 FFF%. 18 19 3.0 0.9 0.0 FF%%. 19 20 3.0 0.9 0.0 FF%%. 20 21 2.9 0.9 0.0 FF%.. 21 22 2.9 0.9 0.0 FF%. 22 23 4.5 0.9 0.0 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) 25-Jul-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000