The material contained in this document is the property of Electronics & Innovation Ltd., it is
subject to change without notice.
May 2016
7
Revision G
"1" key enables telemetry (readback similar to LCD display) - this is the default
mode at power up
Custom commands and display lists can be implemented upon customer
request.
Chapter 3 Technical Description
3.1 GENERAL DESCRIPTION
The 3100LA is designed to amplify signals by 50 dB in the frequency band of 250
KHz to 150 MHz. The signal from the front panel N connector is fed via a length
of 50 ohm coaxial cable into the input of the driver amplifier module. The signal
from the input of the driver is coupled to the input of the MMIC front end. The
output signal of the MMIC is coupled to the gate of transistor Q1. The further
amplified signal appearing at the drain of Q1 is coupled to the input of Q2. This is
transformed to 50
and fed to the driver output N port.
The driver output signal is fed through a length of coaxial cable to the input of the
splitter network. The two output signals are fed to the two power amplifiers. Each
amplifier has a four way splitter the outputs of which are fed to the individual PA
PCBs each containing an RF MosFet that is in a push-pull configuration. The
output of these are then fed to the combining network of the PA module.
The power amplifier module output is fed to the RF bi-directional coupler. The
output of the coupler is then fed directly to the N connector on the front panel,
this is the unit output.
The forward and reverse coupled ports of the bi-directional coupler are fed to the
RF detector which is situated on the main control board. The RF detector feeds a
voltage, which is representative of the true RMS power to the control board
proper. The control board in turn drives the front panel display.
The main power supply unit provides a 24 VDC 12 ampere source. It is a switch
mode power supply unit. The output feeds the PA and the drive amplifier. The
main power supply also has a 5 VDC output which feeds the control board.
