Above 400 MHz the ionosphere is irrelevant. What matters is what is physically between you and the other station.
WHY TERRAIN AND WEATHER DECIDE EVERYTHING
Above 400 MHz the ionosphere is irrelevant. What matters is what is physically between you and the other station.
Ducting works here too, and often better than on 2 meters — the higher the frequency, the tighter it stays in the duct.
Rain starts to cost you at these frequencies, and it gets worse the higher you go. This is also the band for satellites and for bouncing signals off the moon.
WHEN IT WORKS
BEST · Same inversions that lift 2mWORST · Heavy rainWATCH · Ducting · satellites · rain fade
WHO MAY TRANSMIT WHERE · 47 CFR §97.301
FREQUENCY (MHz)
MODE
LICENSE CLASS
420.000–432.000
ATV / mixed
Technician and above, General, Advanced, Extra
432.000–433.000
Weak signal / moonbounce
Technician and above, General, Advanced, Extra
433.000–435.000
Digital & simplex
Technician and above, General, Advanced, Extra
435.000–438.000
Satellite
Technician and above, General, Advanced, Extra
438.000–450.000
FM repeaters
Technician and above, General, Advanced, Extra
Is 70 centimeters open right now? The Ham Radio IQ app shows the MUF and LUF over your head this minute, whether this band is above or below them, and a map of real contacts being heard worldwide. See the board →