Tait TM8250 Operator's Manual page 92

Dialling a new network
This feature is only available for radios with alphanumeric
keys.
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92 Operating in MPT trunked mode
Dial *700# to display the name of the current trunked
network.
Dial *70n# to change to a new network, where n is the
number of the new network (1 to 4).
The radio will restart, and display a power-up message
followed by the name of the new network.
Check that the amber LED is glowing and the network
symbol appears in the display. If the amber LED and
network symbol keep flashing, you may be out of the
coverage area of this network.