Kenwood TKR-850 Service Manual page 51

TKR-850
Connector Terminal Terminal I/O
No. No. Name
6 CP
7 REF
CN350 1 GND
2 STT
3 8CL
4 CV
5 9CL
6 MO
CN351 1 VO
2 GND
ACC 25 pin D-sub Connector
Connector Terminal Terminal I/O
No. No. Name
1 NC
2 RXD2
3 TXD2
4 AI1
5 AI2
6 AI3
7 DG
8 TD
9 TA
10 RD
11 RA
52
TERMINAL FUNCTION
Terminal function
I Clock input for PLL
I Reference frequency signal input
– Ground
I Switching signal input for TX VCO
I 8V input through the ripple filter
I RX PLL lock voltage
I 9V input through the ripple filter
I Modulation signal input
O TX VCO output
– Ground
Terminal function
– No connection
I Serial data to radio
O Serial data from radio
I Programmable function input 1
I Programmable function input 2
I Programmable function input 3
– Control line ground
I TX data input (data or signalling)
Input impedance: 600Ω
Coupling: AC coupling
Deviation: 0.75kHz (wide)/
0.35kHz (Narrow)
(100Hz 0.5Vp-p input)
I TX audio input (voice)
Input impedance: 600Ω
Coupling: AC coupling
Frequency response: Pre-
emphasis curve
Deviation: 60% deviation
(1kHz 280mVrms ± 25mV input)
O RX data output (voice & data)
Output impedance: 1kΩ or less
Coupling: AC coupling
Non-squelched
Frequency response: ± 2.5dB at
10~3000Hz
Output level: 70~90mVrms
(standard modulation)
O RX audio output (voice)
Output impedance: 1kΩ or less
Coupling: AC coupling
Squelched
Frequency response: De-
emphasis curve
Output level: 360~440mVrms
(standard modulation)
Connector Terminal Terminal I/O
No. No. Name
12 RXG –
13 SPM I
14 NC -
15 EMON I
16 EPTT I
17 SC O Squelch control output
18 NC -
19 TXG -
20 AIO1 I/O Programmable function input/output 1
21 AIO2 I/O Programmable function input/output 2
22 AIO3 I/O Programmable function input/output 3
23 AIO4 I/O Programmable function input/output 4
24 AIO5 I/O Programmable function input/output 5
25 AIO6 I/O Programmable function input/output 6
13 12 11 10 9 8 7 6 5 4 3 2 1
25 24 23 22 21
ACC 15 pin Connector
Connector Terminal Terminal I/O
No. No. Name
1 SB O Power supply output after power
2 SB O Power supply output after power
3 NC –
4 GND –
5 GND –
6 SPG –
7 RD O RX data output (Equal to D-sub
8 RSSI O RSSI output (Analog signal output)
9 SPI I
10 AO1 O Auxiliary output 1
11 AO2 O Auxiliary output 2
12 SPO O External speaker output
13 AO3 O Auxiliary output 3
14 AO4 O Auxiliary output 4
15 AO5 O Auxiliary output 5
Terminal function
RX signal ground
(for RA,RD ground only)
Speaker mute signal input
"L": Mute on
No connection
External monitor switch input
"L": Monitor on, "H": Monitor off
External press-to-talk switch input
"L": PTT on, "H": PTT off
"L": Busy, "H": Not busy
No connection
TX signal ground
(for TA,TD ground only)
20 19 18 17 16 15 14
Terminal function
switch; 1A maximum
switch; 1A maximum
No connection
Ground
Ground
Speaker ground
connector terminal No. 10.)
Internal speaker input
13 10 7 4 1
14 11 8 5 2
15 12 9 6 3