ATU-HP Technical Instruction Manual
Page 6-3 (Page 6-4 Blank)
Section 6 Theory of Operation
Issue 2.0
Figure 6-1 – Block Diagram of ATU-HP Automatic Antenna Tuning Unit
B1950006 VB
ATU CONTROL/
MONITOR PWB
A1
AC INPUT
SERVO RESPONSE
AND
MICROPROCESSOR
CIRCUITS
REGULATORS
VOLTAGE
TEMPERATURE
SENSOR
CONTROLS
PUSH BUTTON
XMTR ON/OFF
TUNE SETUP
INHIBIT MATCH
INHIBIT TUNE
INC/DEC R
INC/DEC L
AC INPUT
FROM XMTR
RF INPUT
50
Ω
CURRENT PROBE
PROBE
SERVO
AUTO DECREASE
AUTO INCREASE
50 CURRENT SAMPLE
Ω
Ω
50 VOLTAGE SAMPLE
LOCAL/REMOTE
Ω
50
VOLTAGE PROBE
FWD/REFLD
POWER PROBE
METER
SWITCHES
METER SELECTION
DECREASE R
INCREASE R
ANTENNA CURRENT SAMPLE
ANTENNA
CURRENT PROBE
MATCHING (R)
NETWORK
VARIABLE
TRANSFORMER
MATCHING
R
MOTOR
TUNING
RF OUT
TO ANTENNA
NETWORK
INDUCTANCE (L)
VARIABLE
INCREASE L
RS-485 SERIAL LINK
DECREASE L
FAN ENABLE (TEMPERATURE DEPENDENT)
COOLING FANS
TO XMTR
SYSTEM STATUS &
TUNING LEDS
L
TUNING
MOTOR