VHF (7610) CIRCUIT DESCRIPTION
5A-6
November 1998
Part No. 001-7600-001
5.4.3 VHF I/O EXPANDER IC5 (MAIN UNIT)
5.4.4 VHF PORT EXPANDER IC11 (MAIN UNIT)
51
BM
Outputs control signal for beep mute cir-
cuit Q10. High = Beep muted.
52-
54
CTDA0-
CTDA2
Output port for CTCSS/DTCS signals.
55
HANG
Input port for the microphone hanger
detection signal. Low = Microphone on
hook.
90
MTONE Output port for beep audio while receiving
and 2/5 tone signals while transmitting.
91
TONED Outputs DTMF signals.
94-
96
OPV3-
OPV1
Input port for option connector J2 state
(main unit).
97
CTCIN
Input port for the CTCSS/DTCS IN
decode signals.
98
SD
Input port for S-meter signal.
99
LVIN
Input port for PLL lock voltage.
100
TEMP
Input port for the transceiver’s internal
temperature.
Pin
No.
Port
Name
Description
2, 3,
10
T1-T3
Output tunable bandpass filter control
signals.
11
T4
Output port for tunable bandpass filter
control signal while receiving and power
control signal while transmitting.
14
REF
Output port for reference frequency
control voltage.
Pin
No.
Port
Name
Description
Pin
No.
Port
Name
Description
4
T5C
Outputs control signal for T5 and R5 regu-
lator circuits Q27, Q28 (main unit). High =
Transmitting.
5
TMUT
Outputs Tx mute switch Q19, Q23 (main
unit) control signal. High = Tx muted.
6
RM
Outputs AF mute switch IC4 (main unit)
control signal for the receiver circuit. High
= No receive audio is emitted.
7
MM
Outputs MIC mute control signal. High =
DTMF signals are output, etc.
11
HORNO
Outputs external device control signal.
High = Matched 2/5-tone signals are
received.
12
AFON
Outputs control signal for the AF amplifier
regulator circuit. High = Squelch is open,
etc.
13
AFHPF
Outputs AF filter control signal. High =
Filter out CTCSS or DTCS frequency.
14
NWC
Outputs receive/transmit passband width
control signal. High = Narrow bandwidth
is selected.
Summary of Contents for 761X
Page 9: ...GENERAL INFORMATION 1 4 November 1998 Part No 001 7600 001 This page intentionally left blank ...
Page 11: ...GENERAL INFORMATION 1 6 November 1998 Part No 001 7600 001 NOTES ...
Page 43: ...PROGRAMMING 4 18 November 1998 Part No 001 7600 001 This page intentionally left blank ...
Page 87: ...UHF 7640 EXPLODED VIEW 7 22 November 1998 Part No 001 7600 001 FOLDOUT VHF Exploded View ...
Page 90: ...8 3 November 1998 Part No 001 7600 001 VHF 7610 MAIN BOARD BOTTOM VIEW FOLDOUT ...
Page 91: ...8 4 November 1998 Part No 001 7600 001 VHF 7610 MAIN BOARD TOP VIEW ...
Page 94: ...8 7 November 1998 Part No 001 7600 001 UHF 7640 MAIN BOARD BOTTOM VIEW FOLDOUT ...