Section 4. Installation
4-7
Jumpers
The jumpers listed in Table 4.
INSTALLATION-4
are used to configure the Model 15P
hardware for the system it is installed in. More detailed explanations and instructions for
jumper placement are contained in the installation instructions.
Table 4. INSTALLATION-4. Model 15P Jumpers
JP#
Name
Function
1
Channel Busy Input
Select input from receiver (position B or out), or pulled high
(position A).
2
PTT-2 operation
Select PTT-2 N.C. (position B) or N.O. (position A).
3
Aux aud rly select
Select auxiliary relay audio (position A and C).
4
PTT-common ground-1
Ground PTT common (IN)
5
PTT-common ground-2
Ground PTT common (IN)
6
Aux-common ground
Ground Auxiliary-relay common (IN)
10
Paging mic/line in
B = mic input (de-emph) A = line input (flat)
13
Aux relay control
Separate (position A), follow PTT (position B)
14
Baud select
One of 300, 600, 1200, 2400, 4800 or 9600.
17
Chnl busy polarity
Normal (position A), Inverted (position B)
ADJUSTMENTS
Two adjustments are necessary to complete the installation of the encoder; setting the tone
and digital output levels. Both adjustments are made with the bottom cover off.
Audio Test Mode
Depress the A + CLEAR keys while at the normal idle prompt (- ) to activate the tone
output test. The encoder will display the prompt “Audio” while in this test mode. The
encoder will close the tone relay and generate a sequence of three test tones at 2000 Hz, 1000
Hz, and 500 Hz (±0.1 Hz) at TB1 pins 3 and 4. Each tone lasts for 1.5 seconds and then
automatically switches to the next tone. The encoder continues to generate these tones until
the test is terminated by pressing the CLEAR key again.
The output levels of all microprocessor generated tone frequencies will be referenced to
these test tones. This test is also useful for checking that the de-emphasis jumper (JP10) is in
the correct position to ensure a reasonably flat modulation level across all of the audible
paging frequencies.
Adjust tone level potentiometer R26 to obtain a standard FM peak channel deviation of
between 3kHz and 5kHz, as observed on a deviation meter or oscilloscope.