The AD903 has many functions for getting various levels of audio into an intercom circuit, or getting the intercom audio “traffic’ out to an amplifier or recorder.
It is also useful as a 2-to-4 wire adaptor for connecting 4-wire communications into and out of a standard intercom circuit.
Both the input and the output are transformer isolated from whatever devices are connected. The wide range of level adjustments will accommodate almost any audio signal.
The ‘Null” control allows you to minimize or even eliminate any “cross-talk’ between the input and output.
The input transformer is a studio grade device and will not degrade any audio that you feed it.
Access to the input and output are via a rear panel 4-pin XLR. Pins 1 and 2 are input and pins 3 and 4 are output.
The AD903 connects to the intercom circuit just as a beltpack does, through a rear panel 3-pin XLR.
The AD903 is also commonly used for connecting to a video camera CCU where a built-in intercom is provided that is not compatible with Pro Intercom or any of the other 200 Ohm unbalanced intercom systems.
The AD903 is powered by the intercom system and requires no batteries or separate power supply.
The AD913 permits communications between a cabled intercom system and any number of standard, simplex, (press-to-talk) transceivers. One of your transceivers is dedicated as base, and connected via its accessory mic/spkr jacks to the AD913. Transmissions from other transceivers (on the same frequency) are then heard at all intercom stations on the same circuit as the AD913. Stations may then transmit to the remote transceivers by simply pressing and holding their signal light button.
The AD913 is connected to the intercom system as is a belt-pack, via the female 3-pin XLR on the rear. The AD913 is powered by the intercom power supply. Connection to the (base) transceiver is made through a 6-pin male XLR, also on the back panel. Pro Intercom can provide connecting cables for most popular makes of transceivers. The cable is NOT included with the AD913 as each is custom and must be ordered as a separate item. The front panel contains two 15-turn potentiometers for matching the send and receive levels of the transceiver to the intercom system.The input stage of the AD913 includes a studio quality microphone transformer. The output is also transformer isolated. Frequency response has been carefully shaped to optimize both intelligibility and long-term listening comfort.
The AD920 Balanced/Unbalanced Interface provides impedance matching and signal conversion between a balanced intercom circuit and an unbalanced intercom circuit. Both channels become audio and light-signal compatible. Power may come from either intercom circuit or from both simultaneously.
This is particularly useful for production crews wanting to use their unbalanced system with a balanced ‘house’ system. Each circuit to be used will require its own AD920.
There are no user-operated controls. Connection is via clearly marked 3-pin XLR connectors; 1 female, 1 male.
The AD950 is a simplified, inexpensive device for connecting your intercom system to a standard telephone line. It is connected to the intercom system just as is a beltpack, through a rear panel 3-pin XLR. A second XLR is provided for looping through to the next station on the circuit.
The connection to the telephone line is done with a standard modular telephone cable.
The AD950 does not have an auto answer feature. When the red LED flashes to indicate an incoming call, moving the hook switch from On to Off will answer the call and connect it to the intercom system. The second modular jack on the rear is for connecting a simple telephone with a DTMF keypad, for initiating calls from the AD950. Simply move the hook switch to Off and dial the number.
A recessed, screwdriver-adjust control on the front panel allows compensation for the varying levels on telephone lines.
The AD950 is powered by the intercom system and does not require batteries or a separate power supply. The front panel green LED indicates that the unit is being powered.