Architects and Engineering Specifications
ALD-800 Transmitter
The transmitter operates on the 72-76 MHz auditory assistance frequencies. Transmitted field strength shall not exceed 8000 µV/m at 30 meters. The operating frequency is factory selectable to eight different channels by means of an internal switch.
Maximum FM deviation should not exceed 75 KHz. Transmitter signal pre-emphasis is 75 µS. Frequency stability is controlled by a phase locked loop synthesizer with crystal reference and accurate within ±.005% over 0-50 degrees C. The transmitter provides a permanently mounted telescoping whip antenna.
The FCC approved transmitter is powered by a UL and CSA listed AC wall transformer providing 9V DC input to the transmitter via a 3.5mm DC jack. The transmitter includes a 1/4” line-in jack, mounted on the rear panel, and 1/4” electret condenser microphone jack with 9V DC power
(at 1.0 mA), mounted on the front panel. Also included, is an adjustable audio level control and a red LED “Power On” indicator. The model number is ALD-800.
ALD-800 Receiver
The receiver operates on a single frequency in the 72-76 MHz auditory assistance band. Frequency stability is controlled by a phase locked loop synthesizer with crystal reference and accurate within ±.005% over 0-50 degrees C. The receiver de-emphasis is 75 µS. The receiver provides a 3.5 mm headphone output jack mounted on the top panel.
The receiver is powered by a 9V alkaline battery. The receiver has an Off/On/Volume control mounted on the top panel, LED lamp to indicate battery strength, and an antenna shall be integral to the earphone/ earbud cord. The receiver model number is ALD-800.
