Kenwood TK-290 Service Manual page 22

TK-290
9. Option Board Terminal
Terminals for mounting the option board are provided at
the bottom of the TX-RX unit. The table below shows the
correspondence between the board and terminals. Discon-
nect R414 and R665 in TX-RX unit when the option board is
attached.
R414
22
CIRCUIT DESCRIPTION
X57-5390-10
Component side
R665
IC607
Fig. 19
9-1. Option port 1 (For ANI board etc.)
Name Function
DATI Data input
Received signal to board
DATO Data output
Modulation (ANI) output
from board
TCONT SP amp control from board
STONE Side tone from board
AUDIH MIC inhibit from board
E Ground
MUTE AF mute from board
SCALL Sel call LED port from board
AUX EM CH request from board
PTT PTT logic to baord
MAND Man down logic to board
EMERG EM CH logic to board
BUSY Busy logic to baord
KEY TX request from board
A+ Power supply for board
9-2. Option port 2 (For voice scrambler etc.)
Name Function
CODE1 Scramble code select port 1
CODE2 Scramble code select port 2
CODE3 Scramble code select port 3
CODE4 Scramble code select port 4
TXOUT Modulation output from
board
RXOUT Received signal output from
board
NC No Connection
E Ground
PTTIO TX (Low) / RX (High) to board
CLR/C Clear (High) / Scramble (Low)
(AUX) to board (C : means Code)
RXAEN Power save request for
board Save : Low
RXIN Received signal input to
board
TXIN Modulation input to board
+V Power supply for board
Note
Reference
1kHz STD Dev →
250~350mVrms
Reference
1kHz/150mVrms →
2.5~3.5kHz/wide
1.25~1.75kHz/narrow
No connection
EM : Emergency
EM : Emergency
TX : Transmission
Switched
Note
LSB
MSB
Reference
1kHz/15mVrms →
2.5~3.5kHz/wide
1.25~1.75kHz/narrow
Reference
1kHz STD Dev →
250~350mVrms
Switched