User's Manual

12 Applied Wireless, Inc.
Noise Reduction (Transmitter and Receiver)
The transmitter and receiver are each equipped with active noise reduction
circuits. However, these circuits are normally turned off (factory preset),
to provide the widest possible frequency response for high fidelity music
listening. If the received audio program has an excessive level of
background noise or “hiss” (especially noticeable during periods of
silence, such as the pause between songs on a CD), activating the noise
reduction circuits in both the transmitter and receiver will minimize the
objectionable noise.
To activate the noise reduction circuits, locate the NR switches on the
transmitter and receiver printed circuit boards (refer to Figures 5 and 6).
Slide the actuator of each switch to its NR position.
Note 1: Be sure to readjust the transmitter’s audio modulation level (as
described on page 6) anytime the noise reduction circuits are either
activated or turned off.
Note 2: The noise reduction switches in the transmitter and the receiver
must be set to match each other (either on or off), in order to maintain
balanced audio frequency response.
User’s Guide – 900MHz Stereo Audio Transmitter & Receiver 5
Selecting the Channel of Operation (Receiver)
The AT900-32 provides 32 user-selectable channels. Referring to Figure
4, use the DOWN and UP buttons on the unit’s front panel to select the
desired channel. Momentarily pressing either button will raise or lower the
displayed channel by one; holding either button continuously will rapidly
cycle the channels up or down as appropriate. If multiple AT900-32
transmitters are operating in a common area to broadcast multiple audio
programs, the AR900-32 receiver can receive any of the desired programs
simply by selecting the corresponding channel.
Figure 4 – AR900-32 Receiver (Front Panel)
Figure 3 – AT900-32 Transmitter (Front Panel)
Set this selector
to the “tens” digit
of the desired
channel
Set this selector
to the “ones” digit
of the desired
channel