Icom ID-880H Instruction Manual - Page 179

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 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 maintain the band width and may possibly interfere with other stations. 1. When using a level meter or oscilloscope, adjust the TX audio output level (DATA IN level) from the TNC as follows. 0.4 V p-p (0.2 V rms) : recommended level 0.2 V p-p-0.5 V p-p (0.1-0.25 V rms) : acceptable level 2. When NOT using a measuring device. q Connect the transceiver to a TNC. w Enter a test mode ("CALL", 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 appear 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. OTHER FUNCTIONS 13 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 161