jotron RA-7203C, Operator'S Manual

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Jotron AS| TR7750C: Operators Manual
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Functional description Page 3-3
P/N: 84748 (G)
received audio if the transmitter is connected to a receiver using the T/R bus available on the
rear panels (for details see chapter 3.2.4)

RS232 serial line
The RS232 serial line that can be used to control radio parameters from an external unit, or
to upload new firmware into the radio unit for future functionality. Details regarding
firmware upgrade is described in the maintenance and repair manual.

Hardware key to change access level: In
order to change the access level (see chapter 5.5.3 for details) a hardware
key must be inserted into the microphone/headset connector before
entering in to the menu system. The hardware key consists of a RJ45
connector where pin no. 4 and 5 (RS232 RX and TX) is connected together.