User Manual DDS200 Digital Demodulation System 070-9952-00

Manual OperationLEDsSpecial operating states are signalled by LEDs on the front-panel of the DDS200.The following LEDs are available:Status LEDs next to the display to indicate input signal errors (signal andsync)Status LEDs next to the display to indicate remote-control operation (REM,LLO, SRQ) LED next to the SPEC FUNC key lights when a special function is selectedLED next to the ALARM key lights when there is an alarmThe SIGNAL? LED signals the absence of an appropriate input signal at thecorresponding receive frequency (RF level too low or too high, RF squelch). TheSYNC? LED indicates synchronization problems. With these two LEDs, it ispossible to have a general overview of the test signal applied.The REM LED signals that the unit is remote controlled. SRQ and LLO arestatus messages for the IEC-625/IEEE-488-bus (refer to Remote Control).The LED located above the SPEC FUNC key lights up when a special functionis activated in this menu. The unit may not be in normal operation.The LED next to the ALARM key signals the presence of an alarm.DDS200 Digital Demodulation System User Manual 2–11