HP 8920A, User Manual

Page: 299 / 658

299
Chapter 8, Signaling Decoder Screen
Using the EDACS Decoder
Define the Control Channel Settings
1. Turn AF Generator 1 off by positioning the cursor in front of the
3.00
value of the
AFGen1 To
field and pressing the ON/OFF key.
2. Select
ENCODER
from the
To Screen
menu.
3. Select the EDACS
Mode
to display the EDACS Encoder.
4. Select the
Data Rate
using the
Standard
field. (4800 or 9600 bps)
5. Enter the
Control Channel
settings.
• The
Number
is your system’s control channel number.
• The
RX Frequency
is the control channel’s receive frequency for your mobile.
• The
TX Frequency
is the control channel’s transmit frequency for your mobile.
6. Enter the
Working Channel
settings.
• The
Number
is the working channel number you want the mobile to be sent to.
• The
RX Frequency
is the mobile’s receive frequency for the selected working
channel.
• The
TX Frequency
is the mobile’s transmit frequency for the selected working
channel.
7. Enter the
Logical ID
number.
8. Enter the
Group ID
number.
9. Enter the
Site ID
number.
Prepare the Decoder for Transmitter Measurements
1. Turn the SQUELCH control on the Test Set fully clockwise.
2. Select
DECODER
from the
To Screen
menu to access the EDACS Decoder.
3. Set the
AF Anl In
field to
FM Demod
to demodulate the signal from your transmit-
ter.
4. Set the
Input Level
field to about one third of the expected deviation. (For example,
if your transmitter’s deviation is 3 kHz, set the
Input Level
to about 1 kHz.)
5. Select the
Arm Meas
field to prepare the decoder. The
Status:
field should indicate
Armed
.
6. Select the
Send
field (under
RX Test
). This outputs the control channel information
specified in the EDACS Encoder.
The mobile should indicate that it is receiving the control channel data.