Introduction
The Model 45 is designed to interface
2-wire full-duplex party-line (PL) intercom circuits with 4-wire audio circuits associ- ated with matrix intercom systems. Appli- cations for the Model 45 include television sports and live-event broadcasting, theme park and theater installations, corporate AV, and industrial testing environments. The unit provides one full-featured two- channel 2-wire-to-4-wire interface. The interface features hybrid circuitry that includes automatic nulling capability. The analog hybrids, under software control, provide excellent audio quality and high return-loss.
The Model 45 can be powered by an ex- ternal source of 24 volts DC. The circuitry is designed so that full isolation from the connected party-line circuit is maintained.
The connected party-line intercom circuit can also provide the Model 45’s operat- ing power. For maximum flexibility the unit is capable of supplying 30 volt DC power and AC terminations, thus creating a
2-wire party-line intercom circuit. This allows direct support for devices such as intercom belt packs.
Configuration settings allow the Model 45’s performance to be optimized. Audio level meters provide user confirmation of system performance during setup and operation. Standard audio connectors are used for interfacing audio input, audio output, party-line intercom, and DC power signals. The Model 45 is housed in a com- pact “half-rack” form factor that meets the needs of broadcast “throw-down” applications. Optional front panels allow one or two Model 45 units to be mounted in one space (“1U”) of a standard 19-inch rack enclosure.
Figure 1. Model 45 Front Panel
Figure 2. Model 45 Back Panel
Model 45 User Guide | Issue Preliminary 2, March 2009 |
Studio Technologies, Inc. | Page 5 |
