Multitone RPR 561, Техническое руководство

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FREQUENCY
COUNTER
POWER
METER*
TEST PROBE
RPR 560
P665 ALIGNMENT JIG
TAG10795-1
RF
MODULATION
METER
RPR 561
TM1200 Issue 1 Page 5 - 26
Figure 15: Transmitter Alignment Connections
d) Connect the RF signal generator to the BNC socket at the base of the P665.
Re-tune the signal generator to ±50Hz of the receiver carrier frequency at a level
of -40dBm.
e) Select external modulation and ALC on the signal generator. Feed the Sinadder
output to the modulation input connector of the signal generator and set FM
deviation to ±3kHz. Check that the Sinadder reads
$
24dB.
f) Reduce the signal generator output level to give 6dB SINAD. Adjust CV3 and CV5
for maximum sensitivity.
g) Reducing the signal generator as necessary, adjust CV2 and CV4 for maximum
sensivity. Re-check settings CV2 and CV4, making sure that any interaction
between the two are minimised.
h) Check that the sensitivity is better than 12dB SINAD for -88dBm signal input.
i) Re-tune the signal generator to 910kHz above the receiver carrier frequency.
Check that the image response is 10dB better than the level recorded in the
previous step.
Transmitter Alignment
20. The transmitter alignment procedure is as follows:
a) Connect the test equipment to the P665 as shown in Figure 15.
b )
Fit a modified case back and a fully-charged battery pack to the transceiver.
c) Set the transceiver into permanent transmit by initiating Engineering Test Mode 4,
or by connecting SK301, pin 1 to pin 10 (Tx Key to 0V).