DATA Jack
This 6-pin, mini-DIN jack accepts AFSK input from a Ter-
minal Node Controller (TNC); it also provides fixed-level
Receiver Audio Output, Push-To-Talk (PTT), Squelch Sta-
tus, and ground lines.
ACC Jack
This 3.5-mm 3-pin jack accepts external ALC (Automatic Level Control) voltage from
a linear amplifier on the tip connection, and accepts a "Transmit Request" command on
the ring connection. The main shaft is the ground return.
The "TX Request" connection, when shorted to ground, puts the FT-
857 into the transmit mode, and sends out a steady CW carrier, for
linear amplifier or manual antenna tuner adjustment.
KEY Jack
This 3.5-mm, 3-pin jack is used for connection to a CW keyer paddle or a straight key.
EXT SPKR Jack
This 3.5-mm, 2-pin jack provides variable audio output for an external speaker. The
audio output impedance at this jack is 4 W ~ 16 W and the level varies
according to the setting of the front panel's AF control.
144/430 MHz Antenna Jack
Connect your 144 and/or 430 MHz antenna's 50 W coaxial cable to this M-type ("SO-
239") connector.
HF/50 MHz Antenna Jack
Connect your HF and/or 50 MHz antenna's 50 W coaxial cable to this M-type ("SO-
239") connector.
KEY
GND
FT-857 Operating Manual
R
P
EAR
KEY
GND
C
ANEL
ONNECTORS
DATA OUT
9600bps
DOT
DOT
DASH
COMMON
DATA OUT
SQL
1200bps
PTT
DATA IN
GND
DATA
EXT ALC
GND
TX REQ
SIGNAL
GND
DASH
COMMON
33