Table of Contents
Advertisement
LO et Kiet
1) Video Signal Processor / Character / Mark Generator
Circuit Operation:
The video signals from the antenna unit are supplied to the ACR (anti-clutter rain) circuit in order to re-
duce clutter from rain or snow. Only when the A.C. RAIN key on the display unit is pressed, the selector
circuit is activated, and the video signals pass through the ACR circuit. After passing through the RC dif-
ferentiation circuit in the ACR circuit, the video signals are sent to the EXP (echo expansion) circuit.
When the FUNC + EXP keys on the display unit are pressed, the video signals are switched to pass
through the EXP circuit by the selector circuit. In the EXP circuit, the pulses of the video signals are
expanded, and the signals are sent to the A/D converter circuit, they are ranked as to their amplitude,
they pass through the gate array circuit, and are stored in the primary SRAM (static RAM).
Video
__
Selector
—
] Selector
A-D Conv.
A.C.Rain
ACR Control
EXP
Control
Data (Video)
ADDER
D-A Conv.
Buffer
Gate Array
(IC42)
(TR13~TR20)
(TR21)
=.
(IC12)
Data (Character)
to
CRT module
D-RAM
for Char.
(I1C33~IC34)
D-RAM
for ECHO
(IC35~IC36)
Address
Gate Array
for Adress
(IC26)
Address
GDC
(IC25)
Fig. 34
Advertisement
Chapters
Table of Contents
