ICOM IC-703 Manuale Utente

70

10

DATA COMMUNICATION

DAdjusting the transmit signal from the TNC

For packet operation the transceiver can be

set to one of two data speeds: 1200 bps or 9600
bps. Data speed is set in initial set mode (item “

36

9600 MODE”; see p.81).

qPush [POWER] for 1 sec. to turn power OFF.

wWhile pushing [LOCK], push [POWER] to turn

power ON.

• Initial set mode is selected and one of its items ap-

pears.

ePush [MENU] one or more times to select the item

“

36 9600 MODE.”

• [M-CH] or [

Y]/[Z] can also be used.

rRotate the main dial to select the data speeds:

1200 bps or 9600 bps.

tTo exit initial set mode, push [POWER] for 1 sec.

to turn power OFF.

yPush [POWER] to turn power ON again.

• The conditions selected in initial set mode are now ef-

fective.

When setting data transmission speed to 9600 bps,
the

DATA

signal coming from the TNC is applied ex-

clusively to the internal limiter circuitry to automati-
cally maintain bandwidth.

NEVER apply data levels from the TNC of over 0.6
Vp-p, otherwise the transceiver will not be able to
maintain the band width and may possibly interfere
with other stations.

Read the instructions supplied with your

TNC carefully before attempting packet operation
with the IC-703.

1. When using a level meter or synchroscope, adjust

the TX audio level (

DATA IN

level) from the TNC as

follows.
0.4 Vp-p (0.2 Vrms): recommended level
0.2 Vp-p–0.5 Vp-p (0.1 Vrms–0.25 Vrms):
acceptable level

2. When not using a measuring device.
qConnect the IC-703 to a TNC.

wEnter a test mode (“CAL”, etc.) on the TNC, then

transmit some test data.

eWhen the transceiver fails to transmit test data or

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.

Main dial

[LOCK]

[MENU]

[MODE] Main dial

[POWER]

[

Y]

[

Z]