Service manual

7-7
April 2001
Part No. 001-9800-203
ALIGNMENT PROCEDURE AND PERFORMANCE TESTS
PERFORMANCE TESTS
NOTE: The computer and RPI are not required to
perform the following tests.
7.4 RECEIVER PERFORMANCE TESTS
1. Connect the RF signal generator to the antenna jack
and a 4.7 ohm speaker load to the external speaker
jack (see Section 7.1.3 for more test setup
information).
2. Select the test mode by turning power on with the
A/D switch pressed (low tier) or with the upper two
option switches pressed (high tier). Select a channel
on the low end of the band, the narrowband mode,
and Group 1 for normal carrier squelch operation.
Refer to Section 3.11 for more test mode
information.
3. Set the generator for the channel frequency with an
output level of 1 mV (–47 dbm) modulated with
1 kHz at 1.5 kHz deviation. Adjust the volume
control for 4.85 V rms across the 4.7-ohm load.
Distortion should be less than 3%.
4. Decrease the generator output to obtain 12 dB
SINAD. The generator output should be 0.35 µV
(–116 dBm) maximum.
5. Also check the channels near the middle and high
end of the band. If the transceiver can also be used
for wideband channels, change the generator modu-
lation to 3 kHz, select the wideband mode (see
Section 3.11), and repeat the preceding tests.
7.5 TRANSMITTER PERFORMANCE TESTS
7.5.1 CHECKING POWER OUTPUT
1. Connect the wattmeter and antenna load to the
antenna jack. See Section 7.1.3 for additional test
setup information.
2. If applicable, select the test mode as described in
step 2 of preceding section. Select a channel on the
low end of the band and Group 1 so that no
subaudible signaling is generated.
3. Select high power output by pressing the SCAN key
(upper option key). High power output is indicated
with low tier models when the green LED is off
and
with high tier models when is not
displayed. Key
the transmitter and note the power output. It should
be the level set as described in Section 7.3.4, step 3,
–0 watt, +4 watts.
4. Press the SCAN/upper key to select low power. It
should be the low level set as described in Section
7.3.4, step 4, –0 watt, +0.5 watt.
5. Also check power output on middle and high
channels.
7.5.2 CHECKING FREQUENCY
Monitor the transmit frequency with a communi-
cations monitor. It should be within 1.5 PPM (at room
temperature, it should be within ± 200 Hz). This also
checks the receive frequency.
7.5.3 CHECKING DEVIATION
1. Select a channel on the low end of the band, the
narrowband mode, and Group 2 to generate 134 Hz
data modulation signal (refer to Section 3.11 for
more test mode information).
2. Key the transmitter and monitor the deviation with
a communications monitor. Deviation should be 800
Hz ±100 Hz. Select the wideband mode (800 MHz
only) and deviation should be 1000 Hz ±100 Hz.
3. Reselect Group 1 and speak into the microphone.
Typical deviation should be 1.2 kHz ±100 Hz in the
narrowband mode and 3.0 kHz ±100 Hz in the wide-
band mode.
4. Also check deviation on middle and high channels.