R.V.R. Electronica PTRL, Руководство пользователя

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PTRL & RXRL LCD
36 / 44 User Manual Rev. 1.2 - 31/01/05
9.5.3 PLL/VCO stage
This stage of the card generates the modulated radiofrequency signal. It is based on
a PLL scheme which uses an integrated PLL model MB15E06.
9.5.4 Driver stage
Before going through the final stage (power amplifier), the RF signal is preamplified
in this stage by the BFR540 transistor. When the exciter is in stand-by, the driver is
inhibited.
9.5 Power Amplifier
The power stage is mounted on a heatsink which enables the dissipation of the
generated heat which is contained in a totally shielded metallic box fixed in the central
part of the bottom back of the unit.
The RF signal coming from the VCO at a level of around 10mW reaches the pilot
stage (BFR96) and is amplified from the final stage (BGY925) up to 10W.
The signal goes through a low-pass filter which provides the elimination of the armonic
emissions.
A directional coupler enables the reading of the direct and forward power of the load,
such signals are then sent to the monitoring card for the necessary controls.
The reading of the direct power is also indicated on the panel card in order to enable
the display of the data on the LCD screen situated on the front panel.
9.6 Telemetry card
This device was designed to give indications to the user concerning the functioning
status of the unit. All the available input and output signals of the unit are indicated on
the DB15 connector.
On the same card there is an "INTERLOCK" BNC connector which switches off the
device. When the central pin is grounded, the output power is reduced to zero until
the connection is removed.
When it is used with an RVR amplifier, this connector is connected to the REMOTE
or INTERLOCK of the power amplifier with a BNC-BNC connector. In case of failure
of the amplifier, the central wire is grounded by forcing the unit to enter in stand-by
mode.