17. Use with External Radio The model RV-M5-X is an OEM version of the FireLine modem which does not contain an internal radio. On the rear panel of the RV-M5-X is a 15 pin D-sub female connector, intended for connection to an external radio. The following table describes the functions of the various pins. Front view of 15 D female connector Pin Number Function Ground 1 8V DC Out 2 3 4 5 TX ON RX ON Radio ON. 6 TX Mod 7 8 9 10 11 No Connect No Connect No Connect No Connect Keyline 12 RSSI In 13 RX Audio 14 Mod Adjust 15 DC In/Out Company Confidential Notes Ground connection 8V DC output. 2A max at 10% duty, 1A max at 25% duty, 250mA max continuous. Active high. 0V when off or in RX mode. 5V in TX mode. Active high. 0V when off or in TX mode. 5V in RX mode. Active high. 0V when external radio should be off. 5V when external radio should be on. Wide-band modulation to the transmitter. Must be DC coupled, flat 0-4800Hz frequency response. 1V p-p nominal for full deviation. In RX mode, this is and open-drain circuit. In TX mode, it is pulled to ground with approximately a 10 ohm impedance. Optional signal. Analog RSSI from external radio to the FireLine modem. Unused in most applications. May be use dto signal BUSY Channel to the modem. High-busy, low=not busy. Wide-band receive audio input. Must be DC coupled to the radio FM discriminator. Flat response from 0 to 4800Hz. DC voltage to adjust external modulation balance. Unused in most applications. 9-16VDC. Directly connected to the DC input jack of the FireLine. 54 Raveon Technologies Corp.