Packet (1200/9600 Bps Fm) Operation - Yaesu FT-818ND Operating Manual

Packet ( 1200/9600 bps FM ) Operation
The FT-818 is designed for operation on either 1200 bps or 9600 bps packet, and set-
up is similar to that described previously for SSB-based modes. A separate Data input
adjustment is provided, allowing you to optimize the deviation on the FM Packet modes
separately from the SSB-based Digital modes. The RX-Data output lines are fixed-level
outputs, not affected by the setting of the AF Gain control.
1. Connect your TNC to the FT-818's rear-panel DATA jack, per the illustration. Note that
different connections are used for 1200 bps and 9600 bps Packet.
2. Use Menu #40 (PKT RATE) to select the desired Packet mode. Once you have entered
the Menu and have selected Menu #40, rotate the
"9600" (bps) as the Packet rate.
3. Press the
icon will appear on the display).
4. You are now set up for reception on Packet. If you are operating on 1200 bps, try now
to connect to another station or node; you may well find that the drive level needs no
further adjustment.
5. If you are having trouble connecting due to insufficient or excessive drive from the TNC
to the FT-818, use Menu #39 (PKT MIC) to set the drive. Use your terminal software's
"test" protocol to send out test tones, and adjust the deviation by rotating the
knob, which will vary the data input level to the FT-818's modulator. Remember to press
and hold in the
the new setting for Menu #39.
The 9600 bps Packet deviation setting is very critical to successful operation, and it
can only be accomplished using a calibrated deviation meter; the optimum setting
is usually ±2.75 kHz (±0.25 kHz). For 1200 bps, the optimum level is much less criti-
cal, with the optimum deviation being between ±2.5 kHz and ±3.5 kHz.
Pin Label
Maximum Input Lebel:
40 mV pp @1200 bps
DATA IN
1.0 V pp @9600 bps
Impedance: 10 kΩ
PTT Ground to Transmit
Maximum Output Level:
DATA OUT
500 mVpp
9600 bps
Impedance: 10kΩ
Maximum Output Level:
DATA OUT
300 mVpp
1200 bps
Impedance: 10kΩ
SQL Open: +5 V
SQL
SQL Clised: 0 V
/ key, as needed, to select the PKT mode (the "PKT"
key for one second when adjustments are completed, so as to save
:
INPUT DC13.8V
GND
Note
Transmitter Operation
knob to select either "1200" or
ANT
KEY DATA ACC
DATA OUT
(1200bps)
PTT
DATA IN
DATA DATA
OUT IN
PTT
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