User's Manual

10 Applied Wireless, Inc.
Internal Settings
The AT900-32 transmitter and the AR900-32 receiver each have internal
jumpers and/or switches (on their respective printed circuit boards) that
are preset at the factory to provide the proper configuration for most
applications. The following sections describe these settings, and provide
guidelines for when it may be necessary or desirable to modify them.
CAUTION!
The AT900-32 transmitter and the AR900-32 receiver both contain
sensitive electronic components on their respective circuit
boards. These devices can be permanently damaged by static
discharge if adequate anti-static procedures are not observed.
Such damage is not covered by the Applied Wireless, Inc.
Limited Warranty. Before attempting to modify any of the internal
settings, discharge any static that may have accumulated on
your body by touching a metal object or surface that is earth
grounded, such as a cold water pipe. In addition, your work area
should be as static-free as possible (for example, do not work in
an area in which the floor is covered by nylon carpeting).
In order to modify any internal settings, the unit’s circuit board must
be removed from the enclosure, as follows:
1. Disconnect the power and audio cables from the unit.
2. For the receiver, remove the antenna. For the transmitter, the
antenna is permanently attached. Do not attempt to remove it.
3. For the receiver, remove the VOLUME knob.
4. For the transmitter, remove the two Phillips screws securing the
front panel.
5. For the receiver, remove the two Phillips screws securing the rear
panel.
6. The two long edges of the circuit board are retained in lengthwise
grooves along the inside walls of the enclosure. Gently slide the
circuit board out of the enclosure. As you remove the circuit board,
hold it by its edges only.
7. Once the internal setting(s) have been modified as necessary,
reassemble the unit by reversing the steps above.
User’s Guide – 900MHz Stereo Audio Transmitter & Receiver 7
EQualization (Receiver)
When headphones or earbuds are used with the receiver, the EQ button on
the receiver’s front panel may be used to select one of four preset audio
equalization (tone) profiles, enabling you to select the audio response
characteristics that you prefer. The chosen equalization profile only affects
the audio from the headphone jack on the rear panel. The audio signals at
the line level audio output phono jacks remain “flat” regardless of the
equalization profile chosen for the headphones.
Momentarily pressing the EQ button will cause the 2-digit CHANNEL
indicator to display the current equalization profile. The four equalization
profiles are as follows:
• E1: No Equalization (flat response)
• E2: Bass Boost
• E3: Treble Boost
• E4: Bass Boost + Treble Boost
Pressing the EQ button again (while the display is indicating the
equalization profile) will advance to the next profile. The 2-digit CHANNEL
indicator will automatically revert to displaying the receiver’s current
channel when the EQ button has not been pressed for two to three seconds.