3-3
Technical description
Chapter 3: Technical description98-144591-D
3.6 PA and Filters module 60-123937 (FCC)
The PA and Filters module includes PA drivers, PA-stage, protection circuits, bias circuits, key circuit and
fi ve low-pass fi lters with relays and relay drivers. The PA and Filters receive the modulated RF input signal
from the RX/EX Signal Path and delivers the amplifi ed and fi ltered output signal to the TX/RX connector
via a receive/transmit relay on the Control/Intercon module.
The low-pass fi lters remove the unwanted harmonic frequencies from the PA signal. The Filpeak and
PAprotec outputs are monitoring signals for the Control/Intercon module. The driver and fi nal power
amplifi er stages are galvanically isolated on input and output as they are supplied directly from the 24
V DC input. The selection of low-pass fi lter is controlled by the Control/Intercon module.
The PA fi lters cover the frequency ranges:
1.6 2.3 MHz
2.3 3.05 MHz
3.05 4.5 MHz
4.5 8.8 MHz
8.8 16.81 MHz
16.81 19.0 MHz
19.0 30.0 MHz
3.7 SMPS module 60-122882 (150 W/250 W)
The Switched Mode Power Supply supplies the low power circuits of the equipment with the various
stabilized voltages required, and provides galvanic isolation from the supply source. The equipment is
supplied from a 21.6 – 31.2 V DC
power source. The module also carries the input fi lter and PA supply output which is not galvanically isolated.
The power supply converts the incoming voltage to 7.5 V, +15 V, -15, and 25 V. The SMPS is switched
on from the Control Unit via the TU-CU Bus SUPPLY ON wire and switched off under software control
via the SUPPLY ON/OFF connection from the Control/Intercon module. The DC supply voltage is sensed
by a BAT INFO detector circuit and fed to the Control/Intercon module for automatic RF output power
adjustment.
3.8 SMPS module 60-126172 (500 W)
The Switched Mode Power Supply supplies the low power circuits of the equipment with the various
stabilized voltages required, and provides galvanic isolation from the supply source. The equipment is
supplied from a 21.6 – 31.2 V DC
power source. The module also carries a protection circuit for over/under voltage, wrong polarity and
error detection. This circuit operates a relay on SMPS module 60-126136.
The power supply converts the incoming voltage to 7.5 V, +15 V, -15, 25 and 30 V. The SMPS is switched
on from the Control Unit via the Scanbus SUPPLY ON wire and switched off under software control via
the SUPPLY ON/OFF connection from the Control/Intercon module. The DC supply voltage is sensed
by a BAT INFO detector circuit and fed to the Control/Intercon module for automatic RF output power
adjustment.
Technical description
To Next Page
Loading...
Need help?
General
