Avcomm Intercom System Installation and Operation Guide

Introduction

This document provides installation and operation instructions for Avcomm intercom and 2-way radio systems, designed for racing and off-road applications.

Installation Instructions

Avcomm Intercoms & 2way radio instructions

Step #1: Location for intercom and radio

Find a suitable location to mount the intercom and mobile radio. Standard mobile radio to intercom interface cables are 3 ft. long. Extensions are available for mounting requirements exceeding 6 feet apart (Part # I0 432). Mount the units away from ignition boxes to prevent RF interference.

Step #2: Mount intercom and radio

Mount the intercom using the provided bracket mounts. Ensure sufficient space behind the intercom for cable connections. Mount the intercom and mobile radio using the manufacturer-supplied U bracket.

Step #3: Headset to intercom cables

Route headset cables from the intercom to each seat. Position cables to avoid excessive heat or damage. Always route cables away from ignition boxes or coils to prevent RF interference. Connect headset cables to the correct positions on the intercom. Ensure the driver cable is plugged into the driver position. Incorrect connection may cause the co-driver's microphone to activate when the driver transmits.

Step #4: Push to talks

For headset direct cables, the push-to-talk (PTT) on the headset is active for car-to-car transmitting. For intercom cables with Nexus off-road style jacks, a remote PTT must be installed.

Hole mount push to talk

Drill a 3/4 inch hole and mount the push-to-talk button. Connect the P0 520-F (or P0 520 for AR502/510 models) and plug it into the back of the intercom. Connect the driver PTT into the PTT jack located below the driver headset jack.

Velcro mount push to talk

Velcro PTTs can be mounted on the steering wheel, grab bar, or shifter. If mounting on the steering wheel, coil the cable around the steering column. Test steering lock-to-lock to ensure the cable does not bind, as binding can cause damage. Connect the P0 520-F (or P0 520 for AR502/510 models) and plug it into the back of the intercom. Connect the driver PTT into the PTT jack below the driver headset jack. Ensure PTTs and their cables are routed away from pinching or binding areas to prevent damage.

Step #5: Intercom to Radio cable

Connect the 5-pin connector (Figure 1) to the pigtail cable from the intercom. Connect the serial-style connector (Figure 3) to the car-to-car radio. Plug the 3.5mm gold plug (Figure 4) into the radio's external speaker port. Connect the 2-pin white Molex connector (Figure 2) to the intercom's power plug. The radio will supply power to the intercom.

Note: Cables may vary by radio brand and model. Not all cables provide power to the intercom.

Step #6: Antenna and coax cable

Select an optimal location for the antenna, preferably the center of a metal or aluminum roof for best performance. ½ wave NGP antennas do not require a ground plane, but a minimum 2'x 2' metal surface area is recommended. Mount the NMO connector (gold) using a 3/8" hole in the roof or roll bar. Ensure the mounting surface is free of paint for a good ground connection. Route the coax cable away from ignition boxes and coils towards the car-to-car radio.

IMPORTANT: Do not coil any extra coax cable. Route it loosely around the car. Coiling can cause transmit problems and reduce radio range.

Step #7: Connect power

Radio: Connect the power cable supplied with the car-to-car radio directly to the battery. Do not remove in-line fuses; this may void the factory warranty.

Intercom: If using an adapter cable, plug the intercom's power cable into the 2-pin white Molex connector on the adapter. If a car-to-car radio is not used, route the intercom power cable directly to the battery.

Note: Route all power cables directly to the battery. Connecting power to ignition or other sources may cause ground loop issues.

Note: The intercoms operate on 9-24V DC and are highly efficient, consuming very low power.

Step #8: Intercom operation

Rotate the VOX (Squelch) control fully clockwise. Turn on the intercom by rotating the volume control clockwise. Put on the headset and position the microphone close to your mouth. Speak into the microphone; your voice should be audible in the headset (VOX intercom with sidetone). Adjust the volume control to the desired level. Rotate the squelch control counter-clockwise one click at a time until the microphones turn off. Speaking into the mic should now activate the VOX and turn the mic on. Increase this level to filter out wind and engine noise.

Note: Positioning the microphone close to your mouth allows for a higher squelch setting, which effectively blocks background noise when mics are off.

Step #9: Car to car radio operation

Turn on the car-to-car radio and select the desired channel. Incoming audio volume is controlled by the radio. Adjust the radio's volume control for optimal loudness. Use the remote push-to-talk on the steering wheel or headset (if using headset direct cables). The intercom's LED will change from green to orange, indicating transmission. The car-to-car radio's LED will turn red, showing radio transmission. The intercom LED will turn red when the car-to-car radio is transmitting.

Note: Refer to the radio's owner's manual for complete radio operation details.

Step #10: Car to car transmit level

The intercom has a preset transmit level, but fine-tuning may be necessary. If transmit volume is too low or excessive background noise is transmitted, adjust the RADIO GAIN control on the back of the intercom. Remove the small round plastic cover. Insert a small screwdriver into the hole. Rotate the control one click at a time. Turning counter-clockwise decreases the transmit level; clockwise increases it. Replace the plastic cover when finished.

Step #11: Music input

The AR550 features a 3.5mm front plug for music input. The AR510 uses a rear Molex cable for hard wiring music devices (see Optional Accessories). For 3.5mm operation, connect a stereo cable between the intercom and the music device. Turn on the music device and set its volume level. As the AR550 is a VOX intercom, music will mute during intercom or radio transmissions. If music is constantly muted, reset the VOX (Squelch) control on the intercom to turn off the mics.

Note: Music volume is controlled solely by the music device.

Step #12: Check installation

Inspect the entire installation. Secure all cables away from heat sources or potential damage points. Verify all bolts and mounting hardware are tight. Once installation is complete, enjoy your off-road adventure and stay safe – communicate!

Optional accessory cable

The AR510/AR550 can connect to cell phones, in-car cameras, and stereo systems via the rear 9-pin detachable Molex plug. This cable is not used if these devices are not connected. To connect these devices, plug the accessory cable into the AUX post on the back of the intercom. Follow the diagram for proper hookup.

Note: When identifying the Molex connector, the aligning bumps are located on the left side.

Cell phone hook up

Follow the wiring diagram for proper speaker and microphone connection. A cell microphone audio control is located behind the intercom's back panel. This control adjusts the cell phone's microphone transmit level. Remove the four screws on the AR550 intercom's back panel. On the circuit board, locate a blue housing volume pot. While talking on the cell phone, rotate this pot until the desired transmit level is achieved. Replace the back panel and tighten the screws.

Optional DSP

Avcomm offers an optional Digital Speech Processing (DSP) upgrade. DSP reduces background noise by 90% for clear communication between driver, co-driver, and passengers. It samples your voice and filters out other sounds. Contact Avcomm for this easy-to-install, high-performance DSP (Part # DSP-B).

Conclusion

Thank you for purchasing the Avcomm intercom system. These intercoms are highly adjustable and can be configured for various applications. For questions or concerns, please contact the Avcomm tech line. Your comments and suggestions are appreciated.

Customer Service and Tech Line: 800 845 7541

Avcomm Products