432 – 438 MHz: This range includes a popular amateur satellite band as well as a few Earth resources satellites.Around 400 MHz is a companion band for satellites transmitting on 150 MHz. 399.9 – 403 MHz: This band includes navigation, positioning, time and frequency standard, mobile communication, and meteorological satellites.This band lies in the wider frequency allocation (225 – 380 MHz) assigned for military aviation. 240 – 270 MHz: Military satellites, communications.Many satellites transmitting on this band also transmit a signal on 400 MHz. Before the advent of GPS it was home to large constellations of US and Russian satellites that provided positioning information (mainly to marine vessels) by use of the Doppler effect). 149.95 – 150.05 MHz: This is used by satellites providing positioning, time and frequency services, by ionospheric research and other satellites.148 – 150 MHz: This tends to be used for uplinks of the satellites that downlink in the 137 – 138 MHz band.Most of the links are found in the upper half of the band (145 – 146 MHz). 144 – 146 MHz: One of the most popular bands for amateur satellite activity.Today (2012), most activity is restricted to 137-138 MHz (which is the current allocation) and consists of meteorological satellites transmitting data and low-resolution images, together with low data rate mobile satellite downlinks (eg Orbcomm) 136 – 138 MHz: This band was used heavily by many different types of satellites in the past.
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