The Transmitter shall operate in the 72-76 MHz Auditory Assistance Band as approved by the FCC. Specifically, the transmitter shall operate on the wideband channels spaced at 100 kHz increments on frequencies of 72.1 to 72.9, 74.7, and 75.5 to 75.9 MHz. The transmitted field strength shall not exceed 80 millivolts per meter at a 3 meter distance. The operating channel shall be selected and displayed by a front panel switch, a limiter and 2:1 compressor shall be included and switch selectable. The transmitter shall be FCC and Industry Canada approved.
Maximum FM deviation shall not exceed ±75 kHz. Frequency stability shall be controlled by a phase-locked loop frequency synthesizer with crystal reference and shall be accurate within ±0.001% from 0-50° C. The transmitter shall permit fitting of a 7" flexible whip antenna mounted through the top cover of the unit, or permit connection of an optional magnet mount antenna, with coaxial cable, to a rear panel connector. Only the particular antenna type intended for this connection shall be specified.
The transmitter shall have XLR connectors for balanced audio inputs and RCA Phono connectors for unbalanced audio inputs. The transmitter shall provide a GROUND LIFT switch for the XLR inputs. There shall be a front panel control to adjust the audio input level with an LED OVERMODULATION indicator.
The transmitter shall be powered by an external AC line to 12 VDC power adapter. The rear panel shall have a power switch and front panel display indication when power is active. The transmitter shall be rack mountable in a standard 1 RU rack steel package. The R.L. Drake ALT72 Assistive Listening Transmitter is specified.
