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Icom IC-208H User Manual

Page 89

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74

11

OTHER FUNCTIONS

11

D Adjusting the transmit signal output from

the TNC

When setting data transmission speed to 9600 bps, the data
signal coming from the TNC is applied exclusively to the in-
ternal limiter circuitry to automatically maintain band width.

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

1. When using a level meter or synchroscope, adjust the

TX audio output level (DATA IN level) from the TNC as
follows.

2 Vp-p (1 Vrms)

: recommended level

1 Vp-p–3 Vp-p (0.5–1.5 Vrms)

: acceptable level

2. When NOT using a measuring device.

q Connect the transceiver to a TNC.
w Enter a test mode (“CAL,” etc.) on the TNC, then trans-

mit some test data.

e When the transceiver fails to transmit the test data or

transmits sporadically (TX indicator doesn’t appear or
flashes):
- Decrease the TNC output level until the transmit indi-

cator lights continuously.

When transmission is not successful even though the
TX indicator lights continuously:
- Increase the TNC output level.