Technical Manual

SRT X-BAND RADAR SYSTEMS
FUNCTIONAL DESCRIPTION
304202P003 3.5 Rev. C
The Pulse Circuit Generator’s function is to generate the necessary high voltage
supplying the Magnetron, according to the previous selections.
The Input Pushing Trigger is TRPUSH and the input Pulling Trigger is TRPULL;
both from SRT_CONTROL Board. To the Pulse Circuit Generator is applied as
well the 700 V from the HVPS Generator Circuit.
To one terminal of the primary windings of the PULSE TRANSFORMER is
applied the 700V whilst the second terminal is connected to the MOSFET (push
and pull).
The pulse is generated in accordance with TRPULL and will be pushed in
accordance with TRPUSH; in fact there is current only when the Transformer is
grounded with the TRPULL. Every time there is 700 V on the primary, there is,
as well, 6 kV on the secondary windings of the PULSE TRANSFORMER.
According with this configuration the R.F. is sent to the antenna from the
Magnetron.
In order to get the best operating conditions for the Magnetron, there is also a
need to energize magnetron filament with a 6.3 V Filament Voltage (voltage
changes slightly depending from the magnetron installed, EEV or NJRC and 12
and 25 kW), named VFIL which is applied to a section of the secondary
windings of the PULSE TRANSFORMER. As result, the signal FIL. sent to the
Magnetron, has always a potential 6.3 V greater than the K potential.
While the SRT is Transmitting, the CURRENT TRANSFORMER generates the
signal MCUR which:
− is used in this circuit to block high voltage to magnetron when current
absorbed by magnetron is too high.
− is sent to the Gate Array of the SRT_Control Board
− is sent to the Microprocessor of the SRT_Control Board
3.2.1.5 SRT_Control Board
The SRT_CONTROL Board (Chapter 9, Figure 9.1.18) is located in the
Electronic assy, and his function is to control all SRT operations.
The SRT_CONTROL Board is divided in the following main circuits
− Microprocessor and Gate Array
− System monitor
− Performance Monitor
− Input and Output Interface