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22
10
OTHER FUNCTIONS
■
Optional HM-75A functions
The optional HM-75A allows remotely selected operating channels,
open the squelch, etc. The switches on the HM-75A function as fol-
lows.
CAUTION:
When connecting the HM-75A to the transceiver,
make sure that power to the transceiver is turned OFF, other-
wise the transceiver may malfunction.
D
Switch action
SWITCH
A
B
UP
DOWN
NORMAL
Smart-Ring
Open squelch
Change the oper-
ating channel
number up.
Change the oper-
ating channel
number down.
While holding HM-75A’s [PTT]
No function
No function
Smart-Ring
Call-Ring
A
OFF
ON
LOCK
B
Lock switch:
Locks all
switches
except [PTT]
Earphone
jack
PTT switch
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