Codan Radio MT-3 - Manual (Page 29)

MT-3 ANALOG RADIO SYSTEMS | USER GUIDE
Chapter 4: Analog System Block Diagrams Page 21
Figure 4-1: MT-3 Simple Analog Repeater Block Diagram
FM RECEIVER
FM TRANSMITTER
CONTROLLER
RF IN
RF OUT
FRONT
END
LOCAL
OSCILLATOR
SQUELCH CIRCUITRY
IF AMP & DEMOD
DE-EMPHASIS
AUDIO
PROCESSOR
RF POWER AMPLIFIER
1 KHz TONE @ -8.0 dBm
= 60% MAX. MOD.
1 KHz TONE @ 60% MAX MOD = -8.0 dBm
DE-EMPHASIS AUDIO (TO SYSTEM REGULATOR SPEAKER)
VOICE BAND
FILTER
FLAT AUDIO
(NO CONNECTION)
DISCRIMINATOR
LPF O/P
(NO CONNECTION)
BALANCED AUDIO
CTCSS
DECODER
OPTIONAL
CTCSS
ENCODER
DISC O/P RX MUTE
REPEATER CONTROL
HANG TIMER
COR
OSCILLATOR
TIME OUT
TIMER
AGC PREAMP
& PRE-EMPHASIS
BALANCED AUDIO
BALANCED LEVEL
COMPRESSION
MAXIMUM DEVIATION
SUBTONE LEVEL
PTT SUB
TONE 1
I/P
FLAT
LOW PASS
FILTER
SQUELCH GATES