Descriptions; Signals From/To Other Units; Nah-692/695/698 - JRC JSS-296 Service Manual

6.2.1 Descriptions

The JSB-196GM consists TRX unit type CMN-1960, PA unit type CMN-1960 and Control unit
type CDJ-1960.
The Control unit consists the CPU, audio amplifier for handset microphone and 1500Hz test tone
generator. The CPU controls the TRX unit, PA unit and input/output signals from/to connected
units.
TRX unit consists AF block, IF block, RF block, DSP block and SYNTH block. The TRX unit
uses the there kind of IF signals 70.455MHz, 455KHz and 20.22KHz for reception and
transmission. DSP block converts the 20.22KHz IF signal to audio frequency. SYNTH block
makes the 70.555 – 100.455MHz 1
selects the input signal to the DSP block. During DSC and NBDP mode the line input is passed to
the DSP block, during TEL mode the microphone signal is passed.
PA unit amplifies the transmission signal to 1 – 2W during AC operation, to maximum 150W
during DC operation, and to about 10W during tune.
6.2.2 Signals from/to the other units.
From/ Connecter
To Name
ANT
PA
(NAH-
692/
695/
698)
Tuner
Accessory
Receive
RX ANT
antenna
Accessory
Modem
(NCT-
196N)
Modem
st
local frequency and 70MHz local frequency. AF block
Pin Signal
No. Name
Transmission signal output.
AC operation: 0 – 2 W
RF OUT
DC operation: 100 W max. (2 MHz), 150 W max. (4 – 25
MHz)
Console
terminal
1 TXD
2 GND
4 Analog
5 PA mute
6 RXD 90
10 -BK 87
RF IN Receive signal.
13 Line in (+) Modulated audio frequency signal input for DSC and NBDP.
14 Line in (-) 600 ohms 0 dBm (-20 -- +10 dBm)
15 GND Signal ground.
16 Line out (+) Received audio frequency signal output for DSC and NBDP.
600 ohms 0 dBm (-20 -- +10 dBm)
17 Line out (-)
2 RXD Reception data from the modem unit.
3 TXD Transmission data to the modem unit.
4 -BK Break signal output to mute the modem unit.
5 GND Signal ground.
6 EXT KEY External key signal input from the modem unit.
7 TX RDY JSB-196GM ready to transmit when low signal.
8 Scan Stop The modem unit stops the scanning when low signal.
Description
(Console type NCU-324/1960)
85 Transmission data to the PA unit.
86 Signal ground.
88 Antenna current analog data.
89 Transmission is prohibited by low signal.
Received data from the PA unit.
Key signal to the PA unit.
87