43
FT-2800M O
PERATING
M
ANUAL
The
FT-2800M
may be used for 1200 bps Packet operation, using most all commonly-
available Terminal Node Controllers (TNCs). Connections between the transceiver and the
TNC are accomplished via the front panel Microphone connector and rear panel External
Speaker jack, per the diagram below.
The audio level from the receiver to the TNC may be adjusted by using the
VOL
knob, as
with voice operation. The input level to the
FT-2800M
from the TNC should be adjusted at
the TNC side; the optimum input voltage is approximately 4 mV at 2000 Ohms.
Setting of the optimum TX Audio level: first, connect the
MH-48
A6J
to the Microphone
connector, and while listening on a monitor receiver, transmit on the
FT-2800M
and press
one or more of the Microphone’s DTMF keys. Note the audio level of the DTMF tones
heard in the monitor receiver, then, after removing the microphone and hooking up the TNC,
set the TX Data level “by ear” to about the same level. In most cases, this level of accuracy
in adjustment will be sufficient for good throughput.
Be sure to turn the transceiver and TNC off before connecting the cables, so as to prevent
voltage spikes from possibly damaging your transceiver.
P
ACKET
O
PERATION
PWR
MHz
REV
LOW
D/MR
Pin 4: GND
Pin 5: PACKET TX IN
Pin 6: PTT
PACKET RX OUT
EXT SP REAR PANEL
(
)
MIC
(
)
DATA
OUT
DATA
IN
PTT
Содержание FT-2800M
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