 Additionally, the IARU bandplan has the 432.1 MHz range (which is used for mode B uplink) marked for "weak signal" in all three Regions.Accessing the Mode B uplink is permitted in the United States under a waiver from the FCC.In the summer of 1982 the Fighting Solidarity in Wrocław learned that AO-7 became periodically functional, when its solar panels got enough sunlight to power up the satellite.