Yaesu FT-920 Operating Manual page 35

transmit. Check with the manufacturer of your ampli-
fier (or other device) to confirm the switching voltage
and current, if it is not clearly stipulated in the docu-
mentation for your equipment.
Be absolutely certain to check the position of the
T -R switch prior to connecting any external de-
R Y
vice to the T G jack. Never connect an AC
X ND
voltage, or a negative DC voltage, to the T
jack if the T -R switch is set to T
R Y
Warranty on this product does not cover damage
caused by improper connections (excessive or im-
proper voltage) to the rear panel jacks of the FT-
920.
(8) 13.5V Jack
This jack provides +13.5V DC at up to 200 mA for
use with low-power peripheral devices. The jack is
fused, and the current is limited by the size of the
copper foil on the internal circuit boards; do not ex-
ceed the 200 mA current limitation.
(9) E S Jack
XT P
This 3.5 mm, 2-pin jack provides speaker audio out-
put for an external speaker. The audio output im-
pedance at this jack is 4
varies according to the setting of the front panel's AF
G control.
AIN
(10) A O Jack
F UT
This is a fixed-level audio output jack for connection
to a peripheral device such as a TNC, Morse code
reader, or WeatherFax decoder. The audio output
level provided is 100 mV at 600 , and the front-panel
AF G control has no effect upon the audio level
AIN
present at the A O jack.
F UT
(11) P Jack
ATCH
This RCA jack is wired in parallel with the front panel's
microphone input jack, providing a convenient input
port for connection of a phone patch or other audio
input. The audio input impedance is 600
signal applied to the P
ATCH
setting of the front panel's M
(12) AFSK-FSK Switch
This switch determines the method of (transmit) Data
input to Pin 1 of the D
ATA
AFSK is selected, then Pin 1 should be connected to
the "TX Audio" line from the TNC. If FSK is selected,
then Pin 1 should be connected to the "FSK Out" line
from the TNC or TU.
FT-920 Operating Manual
G
X ND
. The Limited
R
~ 16 , and the level
, and the
jack is affected by the
G control.
IC AIN
jack (described below). If
(13) D Jack
ATA
This five-pin DIN jack accepts AFSK input or FSK
(closure to ground) input from a Terminal Node Con-
troller (TNC) or Terminal Unit (TU); it also provides
fixed-level Audio Output, PTT, and Ground lines. The
optimum AFSK Input level is 30 mV at 3 k , while
the Audio Output level provided is fixed at 100 mV at
600 .
(14) E ALC Jack
XT
This RCA type connector may be used for connec-
tion to a linear amplifier's ALC cable. The specified
control voltage range is 0V ~ -4V DC, with -4V corre-
sponding to the maximum degree of power reduc-
tion being applied to the FT-920.
(15) RX A Jacks
NT
These RCA connectors provide convenient access
to the receiver input line for a number of applications.
They are active only when the front-panel [RX A
key is pressed.
The O jack is connected to the "RX" lead from the
UT
main T/R relay for the transceiver.
The I jack is connected to the input port of the FT-
N
920 receiver section.
Accordingly, a separate receive-only antenna, or a
VHF receive converter's 28 MHz output, may be con-
nected to the I jack. Alternatively, a receive
N
preamplifier's Input jack may be connected to the O
jack, and the preamp's Output jack may be connected
to the I jack. See page 35 for interface instructions
N
and ideas.
(16) A Jacks (A - B)
NT
These SO-239 ("M") jacks should be connected to
an appropriate coaxial connector for the antenna or
a 50 dummy load. Antenna selection is made via
the front-panel [A A/B] switch.
NTENNA
(17) DC 13.5V Jack
This is the main DC input jack for the transceiver.
The specified voltage is 13.5V DC (negative ground)
at 20 Amps.
(18) GND Lug
For best performance and safety, this Ground Lug
should be connected to a good earth ground, using a
short, heavy, braided cable.
]
NT
UT
33