Icom IC-207H Instruction Manual page 69

D 1200 bps packet operation
q Connect the IC-207H and a TNC as illustrated below.
DATA IN
GND
PTTP
SQ
AF OUT
w Set the TNC for transmit.
e Set transmit delay on the TNC to 30–50.
r Adjust the TNC frequency deviation if necessary.
• When using a deviation meter:
Adjust the output of the TNC so that frequency deviation is in the
range ± 3 to 4 kHz.
• When NOT using a deviation meter:
A receiver or transceiver is needed to monitor the transmission—
compare the received audio output level when receiving a TNC
modulated signal with high level voice signals using the micro-
phone. Then adjust the TNC modulated signal to a lower level
than the voice modulated signal.
TNC SIDE
TX AUDIO
GND
RX AUDIO
PTT
SQL
OTHER FUNCTIONS
NOTE:
• Read the instructions supplied with your TNC carefully
before attempting packet operation with the IC-207H.
• Pin t AF OUT is for 1200 bps operation only. This pin
cannot be used for 9600 bps operation.
• Over modulation may degrade signal quality. If you find
that many transmissions are failing, re-adjust the modu-
lation level.
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