79
10
DATA COMMUNICATION
2001 NEW
■
Adjusting the TNC output level
When setting data transmission speed to 9600 bps,
the data signal coming from the TNC is applied exclu-
sively to the internal limiter circuitry to automatically
maintain band width.
NEVER
apply data levels from the TNC of over 0.6 V
p-p, otherwise the transceiver will not be able to main-
tain the band width and may possibly interfere with
other stations.
D
D
Using with a level meter or synchroscope
When using a level meter or synchroscope, adjust the
TX audio output level (DATA IN level) from the TNC as
follows.
0.4 V p-p
(0.2 Vrms)
: recommended level
0.2–0.5 V p-p
(0.1–0.25 Vrms)
: acceptable level
D
D
Not using a measuring device
q
Connect the transceiver to a TNC. (p. 77)
w
Enter a test mode (“CAL,” etc.) on the TNC, then
transmit some test data.
e
When the transceiver fails to transmit the test data
or transmits sporadically (TX indicator doesn’t light
or flashes):
- Decrease the TNC output level until the transmit
indicator lights continuously.
When transmission is not successful even though
the TX indicator lights continuously:
- Increase the TNC output level.
■
Data transmission speed
For data communication (in FM mode), the transceiver
can be set to to a maximum data speeds of 9600 bps
(or less; 1200, 2400 or 4800 bps).
q
Push [MENU] for 1 sec. to enter set mode.
w
Push [F1
≤
] or [F2
≥
] to select the
9600bps
Mode
item.
e
Rotate the tuning dial to turn the 9600 bps mode ON
and OFF.
ON
: 9600 bps of data speed
OFF
: 1200, 2400 or 4800 bps of data speed
(default)
r
Push [MENU] to return to previous indication.
2 1
O N
9 6 O O b p s M o d e
2 1
O F F
9 6 O O b p s M o d e
Select with the tuning dial
IC-7400.qxd 02.4.2 11:35 Page 79
