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RADIOBEACON TRANSMITTER
ND500II (125 WATTS) DOUBLE SIDEBAND - NO VOICE
Page 2-14
15 September 2003
Figure 2-2 Block Diagram – ND500II Radiobeacon Transmitter
EXTERNAL DC
S1580128 SHEET 1 OF 1 V1
50VDC
24VDC
15VDC
DDS
POWER SUPPLY
BATTERY ON/OFF
REGULATOR
SWITCHING
CHOKE
RECTIFIER/
EXTERNAL RF DRIVE
(OPTIONAL)
AC POWER
SUPPLY
CODE
GENERATOR
GATE
KEYING
OSCILLATOR
TIMING
OSCILLATOR/RF DRIVER
TONE
KEYED
SELECTOR
TONE
OSCILLATOR
KEYER
MODULATOR DRIVER
MODE
SELECTOR
EMISSION
MODE
GENERATOR
RF DRIVE
AMPLIFIER
INTERNAL
STANDBY CODE
PULSE
WIDTH
MOD
DRIVE
PA/MODULATOR
AMPLIFIER
POWER
HARMONIC
RF POWER
CHANGEOVER
HARMONIC FILTER
STANDBY
TRANSMITTER
(OPTIONAL)
MODULATOR
DRIVE
RF
FILTER
PROBE
RELAY
(OPTIONAL)
RF OUTPUT
CHANGEOVER
SIGNAL
FWD
PWR
REFLD
PWR
MONITOR
EXTERNAL CONTROLS
VISUAL ALARMS
EXTERNAL ALARMS
PARAMETERS FOR
REMOTE MONITORING
MAIN TRANSMITTER