Telex 38109-977 manual Determining Intercom Needs, two-wire, four-wire, or both?

Determining Intercom Needs, two-wire, four-wire, or both?

In determining intercom needs for a specific application, we begin by first giving examples of intercom requirements. Then, we will attempt to specify an RTS™ intercom system to fill that requirement. Although specific applications are presented, we finish with a general discussion of how to determine whether a given system should be two-wire, four-wire, or some combination of each system.

Before we begin, we should again mention that although analog two-wire conference intercoms continue to carry basic communications for many smaller production facilities, digitally controlled matrix systems offer a range of flexible alternatives. By integrating various forms of communications features, the four-wire matrix system for larger applications makes the difference between confusion and a successful production session.

Small Studio or ENG Vehicle

Previously, we presented the example of the ENG vehicle with its small two-wire system. We have also determined this application requires at least two forms of communications: conference and IFB

To fill the need of a small studio or ENG vehicle, we propose the MCE325 system with its inherent simple IFB (meaning no tally or priority). As shown below, the MCE325 and its associated components make an excellent choice for this application. The powerful MCE325 intercom panel has the capability to produce two conference channels and two IFB channels, which is perfect for the electronic news gatherer. There are many other configurations available in the highly versatile and user programmable MCE325, including four-wire, vox, relays for radios, and many others.

Note A small four-wire matrix system such as the Zeus could have been specified, but probably would have been overkill for this application.

In essence, the client now has saved several thousand dollars using a small, but extremely versatile intercom system.

Figure 2. The Model MCE325 provides the intercom backbone for the typical ENG vehicle or small studio.

MCE325 Modular Programmable Station

This unit is available in many physical configurations. For this application, we specify the MCE325-K. The ‘K’ designator includes the MCE325, MCP1 (1U rack kit), MCS325 modular speaker, and the MCP6 removable panel microphone. The four talk buttons on the panel are Talk1, Talk2, IFB1, and IFB2. Talk 1 and 2 operate the two conference channels. The rear panel channel 1-2 connector ties to the TW5W 1x5 Splitter while its loop-through connects to the PS15. The channel 3-4 connector ties to the IFB325 talent stations. The MCE325 has a headset connector to allow the director to use the system privately, if desired. Other MCE325’s can be interconnected to the director’s panel. IFB capabilities are retained on other MCE325 panels via a special keying circuit that allows the slave units to operate the master unit IFB.

PS15 Power Supply/MCP2 Rack Kit

The PS-15 power supply and its MCP2 single component rack kit (not shown) provide operating power for both the BP325 programmable belt packs and IFB talent stations.

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