SWS GRAFEX HF FREQUENCY PREDICTIONS ADDRESS NO. 1234 =============================================================================== Circuit: Bunbury Perth Date: 28 April, 2026 T-index: 80 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 6.9 2.9 2.3 FFFF%%. 00 01 7.8 3.4 2.7 AFFFF%%. 01 02 8.3 3.8 2.9 AFFFFF%. . 02 03 8.6 4.0 3.0 ABFFFF%% . 03 04 8.6 4.0 3.1 BFFFF%% .. 04 05 8.8 4.0 3.1 BFFFF%% .. 05 06 8.7 3.9 3.0 AFFFFF%% .. 06 07 8.6 3.6 2.8 AFFFFF%% .. 07 08 8.3 3.2 2.6 AFFFFF%% . 08 09 7.8 2.5 2.0 AFFFFF%%. 09 10 6.5 0.5 0.0 FFFFFF%%. 10 11 5.1 0.5 0.0 FFFFF%.. 11 12 4.4 0.5 0.0 FFFF%.. 12 13 4.0 0.5 0.0 FFF%%. 13 14 3.9 0.5 0.0 FFF%.. 14 15 3.8 0.5 0.0 FFF%.. 15 16 3.7 0.5 0.0 FFF%.. 16 17 3.7 0.5 0.0 FFF%. 17 18 3.6 0.5 0.0 FFF%. 18 19 3.5 0.5 0.0 FFF%. 19 20 3.4 0.5 0.0 FFF%. 20 21 3.2 0.5 0.0 FFF%. 21 22 3.3 0.5 0.0 FFF%. 22 23 5.1 1.4 1.2 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) 28-Apr-2026 BoM Space Weather Services, Sydney Australia +61-2-9213-8000