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RF Technology R50
is 388mV.(eqvt to 0dBm into 600 ohms)
Enter < RET> when done.
Set the RF signal generator's output to -60dBm
Enter < RET> when done.
rssi_scale is 0.417dBm/dac step, and rssi offset is -137.500dBm)
Adjust the Modulation to only 1KHz max deviation
Enter < RET> when done.
deviation_scale is 1.000dBm/dac step, and
deviation offset is .000dBm
Adjust the Carrier Squelch to the desired level
Enter < RET> when set.
-99.5
--- for example
Enter the Fast Noise Threshold(in dBm):
Enter the Carrier Alarm Threshold(in dBm):
Set the RF generator output to the desired level ( < -105dBm ),
and adjust the N.SQ adjustment counter clockwise
until the squelch opens, thence turn it clockwise
until the noise is muted.
Enter < RET> when done
6.5 The " Refer ence" Calibr ation Pr ocedur e
R50>
cal ref
To compensate for crystal ageing and other parameters that drift, the following
procedure should be performed approximately once per year.
Open the cover of the receiver, find out the test point TP209 on receiver PCB, using a
frequency counter to measure the frequency and follow the instruction as
bellow:
Measure the ECLK frequency, accurate to 0.5Hz
and enter the result(in MHz, eg 7.3727965)
Measure the E clock frequency again, and enter yes(y/Y)
if less than 1Hz from prev. freq, or re-enter the frequency
Connect an RF generator to the input
and with output freq of 37.5MHz and output level of -100dBm
Enter < RET> when done.
7 SPECIFICATIONS
7.1 Over all Descr iption
The receiver is a frequency synthesized, narrow band, HF/VHF, FM unit which can be
used in conjunction with transmitter and power supply modules as a base
station, or it can operate as a stand alone receiver. All necessary control and
600 ohm line interface circuitry is included.
7.1.1 Channel Capacity
Although most applications are single channel, the R50 can be programmed for up to
256 channels, numbered 0-255. This allows a network administrator to
program every receiver, in every site, the same way. By setting each site up to
select which of the 256 channels is appropriate, any receiver can be plugged
