7
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. Trans mit ter signal pre-emphasis is
75 µS. Frequency stability is controlled by a
phase locked loop syn the siz er 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 as sis tance
band. Frequency stability is controlled by a
phase locked loop synthesizer with crystal
reference and accurate within ±.005% over
0-50 de grees 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.
