NX-200
17
Q405
50T SW
Q401
50R SW
Q402
50IF SW
IC400
AVR
/SAVE
/5TC
5RC
SBC
CN400
50R
50IF
+B
50C
50T
RX circuit
RF Final AMP
APC
VCO
TX circuit
IF circuit
IC402
DC/DC
150C
Assist, Tune
IC403
DC/DC
-10V
LCD Bias
31BU
SRAM, RTC
IC403
AVR IC
33C
PLL, VCTCXO
Q403
SB3 SW
SB3
TX/Busy LED
F400
2.5A
IC411
AVR IC
5UC
50U
Universal
IC416
AVR IC
Q409
31BU
IC708
AVR IC
5A
Option
Q403
SB2 SW
SBC
SB2
BackLight
Key Light
33M
SB1
ASIC, DSP I/O,
Flach, LCD DRV
IC407
DC/DC
IC404
AVR
VOL SW
15M
ASIC, DSP core
IC717
DC/DC
33A
/PSW
/BINT
ASIC Analog,
Audio
IC406
AVR
IC414
Detect
Q408
AND
D408
OR
D412
OR
Q402
Lvl Conv
IC108
ASIC
Q401
Lvl Conv
CN404
Control unit (X53)
SBC
TX-RX unit (X57)
Fig. 8 Power supply circuit
8. Signaling Circuit
8-1. Encode (QT/DQT/LTR/DTMF/2-tone/MSK)
Each signaling data signal of QT, DQT, LTR, DTMF, 2-tone
and MSK is generated by the DSP circuit, superposed on
a modulation signal and output from IC108. The modula-
tion balance of the QT/DQT/LTR signal is adjusted by the D/
A converter(IC703) and the resulting signal is routed to the
modulation input of the VCO and VCXO (X1). Each deviation
of the TX QT, DQT, LTR, DTMF, 2-tone and MSK tone is ad-
justed by changing the output level of IC108 and the result-
ing signal is routed to the VCO and VCXO. The RX DTMF
tone is routed to the receive audio signal system, and is
output from the speaker.
8-2. Decode (QT/DQT/LTR/DTMF/2-tone/MSK)
The audio signal is removed from the FM detection
signal sent to the DSP circuit and the resulting signal is de-
coded.
9. Compander Circuit
The term “compander” means compressor and expand-
er. The compander reduces noise by utilizing a compressor
and an expander. The transceiver contains a DSP (IC102) to
perform this operation. The transceiver compander can be
turned on or off using the FPU.
CIRCUIT DESCRIPTION