R.V.R. Elettronica RXRL-NV, Техническое руководство

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RXRL-NV Technical and Maintenance Manual
R.V.R. Elettronica S.r.l. (Bo) Pag. 28
operating frequency to have been programmed.
The green LOCK led should switch on within 30 seconds indicating
that the oscillator has locked to the operating frequency
displayed. The display has five digits, 3 before the decimal
point representing (from left to right) hundreds of MHz,
tens of MHz and MHz; and 2 after the decimal point represent-
ing hundreds and tens of KHz. To change this number, use the UP
(14 Fig.1) and DOWN (12 Fig.1) buttons to respectively increase
it and decrease it.
Once the desired frequency has been found, press ENTER (13 Fig.1)
to confirm and save it.
As soon as the ENTER button has been pressed, the LOCK led will switch
off (providing that the new frequency is different from the old),
indicating that the VCO is re-tuning to the new frequency.
If the ENTER button is not pushed, the display will flash the new
value four times and then reset to the previous value.
NOTE: The receiver will continue to function normally at the same
frequency, throughout the procedure described above, until the ENTER
button is pressed.
Note that a momentary press of the UP and DOWN buttons will increment
or decrement the rightmost digit by 1 (corresponding to a frequency
change of 10KHz).
A longer press of either button will cause the display to increment
or decrement continuously until the button is released.
Furthermore, when the limit of the operating frequency band is
reached, the displayed frequency will jump to the other limit and
carry on changing in the direction corresponding to the button being
pushed.
NOTE: The frequency band is pre-defined by the user and rarely exceeds
25 MHz.
Exemple: Band 840-860 MHz:
UP button pressed: 859.99 860.00 840.00 840.01
DOWN button pressed: 840.01 840.00 860.00 859.99
After the PLL has been locked for about 90 seconds, the display turns
off automatically.
To switch it on, press the ENTER button.
6) Connect an audio analyzer to the MONO (3 Fig.1) or MPX outputs
(6 Fig.1).
Using an R.F. signal generator, inject a carrier at the receiver’s
operating frequency into the R.F. input of the receiver, at a level
of -47dBm.
Modulate the carrier with a 400Hz tone at a deviation of ±75Khz.
Check that the analog meter (21 Fig.1) displays a reading of 1mV.
7) Select CENTER with the selector (20 Fig.1) and check that the