R.V.R. Elettronica PTRL-NV/2/S3, Техническое руководство

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R.V.R. ELETTRONICA S.r.l. (BO) Pag. 17
PTRLNV/2/S3 and PTRL-NV/2/HP/S3 - Technical and Maintenance Manual
parameters may be remotely controlled via an optional 9 pin D-type serial
port.
In the absence of mains power, a non-volatile memory maintains
indefinately, the last frequency that was programmed.
2.7 MODMETER
This card is mounted on the left side of the front panel (Photo 1).
This circuit allows the deviation of the VCO frequency to be displayed
by rectifying the signal supplied to the Main card. The card has two
connectors; one for the mono signal and the other for the stereo signal.
A switch allows the gain of the measuring circuit to be set to 10% or
100% for a more precise reading of low-level deviation (eg. SCA, RDS,
MPX pilot tones). Another switch sets the display mode to bar-graph or
peak mode. The display comprises 14 green leds and 6 red leds. In the
100% display mode, each led represents 5 KHz of deviation with the first
red led representing 75 KHz and FDS at 100 KHz. In the 10% mode, each
led represents 0.5 KHz of deviation.
2.8 ANAMETER
This circuit comprises two cards and a meter mounted on the right
hand side of the front panel (Photo 1-2). This sub-assembly displays the
values of various operating parameters of the transmitter: internal
voltages and currents, direct power and external 24V. The parameters are
selected by a lever switch (13 Fig.1) and the selection is indicated by
the legend of the green led (14 Fig.1).
The readings are taken using the corresponding scale:
MEASUREMENT SCALE FDS
Audio Level dB +3 dB
Internal voltages V 30 V
Internal currents A 6 A
Direct power W 10 W
Reflected power W 50 W
This circuit also features a red UNLOCK led (16 Fig.1) and a red SWR led
(15 Fig.1), controlled by the power supply. In addition there are: a red
power led (19 Fig.1), a power output PWR trimmer (10 Fig.1) and the mains
supply switch (18 Fig.1).
2.8 DOUBLER
This card is mounted to the left side of unit, in a central position.
The circuit doubles the frequency of the VCO output at a level of about
7-10dBm, and the output is supplied to the input of the R.F. Power
Amplifier.