The material contained in this document is the property of Electronics & Innovation Ltd., it is
subject to change without notice.
September 2010
7
Revision A
In the default state, the RS-232 port will echo the same information sent to the
front panel LCD display, allowing a running datalog to be stored to disk using the
capture feature of the terminal program.
Single character commands can be sent to the amplifier to achieve the following:
"1" key enables telemetry (readback similar to LCD display) - this is the default
mode at power up
“2” key clears any faults and tries to start the supply.
“0” key disables telemetry (Complement to “1” key)
Chapter 3 Technical Description
3.1 GENERAL DESCRIPTION
The A1000 is designed to amplify signals by 60 dB in the frequency band of 300
KHz to 35 MHz. The signal from the rear panel N connector is fed via a length of
50 ohm coaxial cable into the input of the pre-amp, the first stage is 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 BNC port.
The driver output signal is fed through a length of coaxial cable to the input of the
IPA, the output is fed to the power amplifier splitter. This splitter has four outputs.
Each output is then fed to each of the four PA rf trays. Inside each rf tray the
signal is split again four ways and fed to each of the four PAs in the tray. In each
PA module the signal is split into two equal phase and amplitude signals. These
signals are fed to the inputs of transistors Q1 and Q2. The amplified signals
appearing at the drains of Q1 and Q2 are then fed to the output BNC port via the
impedance matching network. The output of the four modules is then fed to a
combiner to produce a single signal for each rf tray. The output of each rf tray is
fed to the control/ combiner tray when the four signals are combined to produce a
single output.
The power signal is then fed into a length of 50 ohm coaxial cable to the RF bi-
directional coupler. The output of the coupler is then fed directly to the N
connector on the rear 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.