TS-590S
11
■
From the second IF to the AF output
The signal that passed through D525 then goes through
D526 and enters the FM wave detecting IC (IC591) in FM
mode, and the AM/SSB/CW/FSK wave detecting mixer
(D551, D552) in other modes.
The FM mode signal is mixed with LO3 (10.240MHz) in
the FM detecting IC (IC591), and converted into the third
IF (455kHz). The third IF signal passes through the ceramic
fi lter (CF591), demodulated into audio signals, and is then
amplifi ed by the FM AF amplifi er (IC592).
Signals of modes other than FM are mixed with LO3 (RX-1
path: 11.398MHz, RX-2 path: 10.719MHz) in the AM/SSB/
CW/FSK wave detecting mixer (D551, D552), are converted
into the third IF (24kHz), and are then amplifi ed by the third
IF amplifi er (Q551).
Q321~Q324
1st Mixer
TX
Q263~Q266
1st Mixer
Q281,Q282
LO1 Amp1
Q351,Q352
LO1 Amp2
Q431
LO2 Amp
XF371
73.095MHz
Q391
1st IF Amp
D422,D423
2nd Mixer 10.695MHz
11.374MHz
LPF
+
11.374M
NOTCH
RX-1
RX-2
LO1
from Pre Amp
(Q236)
LPF
~60MHz
MCF
73.125~133.095MHz
13.174~32.195MHz
XF301
11.374MHz
MCF
TX
TX
to 2nd IF Amp1
(Q451)
LO2
62.4MHz
10.695M 15k
XF472
D476
AGCV
D471
D443
IF input
(10.695M)
IF input
(11.374M)
D441
Q451
2nd IF Amp1
Q541
2nd IF Amp2
Q521,Q522
2nd IF Amp3
D461~D464
Blanking
10.695M 6k
XF471
D475
D474
11.374M 500
D478
D473
10.695M 2.7k
XF473
D477
D472
11.374M 2.7k
XF474
XF475
D477
D472
D522~D524
ATT
IFGC
IF output
(10.695M/11.374M)
D525
ATT
Fig. 4 From the preamplifi er (Q236) to the second IF frequency (10.695MHz/11.374MHz)
Signals of FM mode and modes other than FM are sent
from the TX-RX unit (X57-785 A/2) RIF connector (CN600) to
the Control unit (X53-446 A/3)’s CN61.
The signal input into the Control unit (X53-446 A/3) is am-
plifi ed in the operation amplifi er (IC64, IC65), A/D conversion
is carried out by the A/D converter (IC66), and then the DSP
(IC301) fi ltering, volume control, subtone decoding, etc. are
carried out. The output signal from the DSP is converted by
the D/A converter (IC72), amplifi ed as an audio signal in the
AF power amplifi er (IC67), and is then sent from the Control
unit (X53-446 A/3) AF connector (CN65) to the TX-RX unit
(X57-785 A/2) CN3, and output to the PHONES jack (J951)
(fi rst priority), EXT.SP jack (J1) (second priority), or internal
speaker (third priority).
CIRCUIT DESCRIPTION
Содержание TS-590S
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