
Chapter 27
Transmit Inhibit
The Transmit Inhibit feature allows you to stop all transmission including voice and data. The radio can
receive messages but not able to reply the acknowledgment request of the received message.
This feature is available for APCO 25 Trunking, Type II Trunking and Conventional operations for all
APX radios.
You can physically control the transmission of the radio especially during operation in hazardous
environments. An environment is considered hazardous if radio transmission could initiate an explosion
or other dangerous reactions.
27.1
Enabling or Disabling Transmit Inhibit
Procedure:
To enable or disable transmit inhibit, press the
TxIn
menu item.
If Transmit Inhibit is enabled, your radio shows the following indications:
• A tone sounds.
• The display shows
Tx inhibit on
.
NOTE:
If you press the
PTT
button, a negative tone sounds.
If Transmit Inhibit is disabled, your radio shows the following indications:
• A tone sounds.
• The display shows
Tx inhibit off
.
The status of the Transmit Inhibit does not change after the radio powers up.
27.2
Smart PTT (Conventional Only)
Smart PTT is a per-personality, programmable feature used to keep radio users from talking over
other radio conversations. When Smart PTT is enabled in your radio, you cannot transmit on an active
channel.
The following table shows the variations of Smart PTT.
Mode
Description
Transmit Inhibit on Busy Channel with Carrier
You cannot transmit if traffic is detected on the
channel.
Transmit Inhibit on Busy Channel with Wrong
Squelch Code
You cannot transmit on an active channel with a
squelch code or (if secure-equipped) encryption
key other than your own. If the PL code is the
same as yours, the transmission is not prevent-
ed.
MN009203A01-AA
Transmit Inhibit
87