Operating Manual Vol 1 - ES Documentation

Modulation - GeneralSMIQEXT1/EXT2-InputsThe external modulation signal for AM, FM and PM at inputs EXT1 and EXT2 must show a voltage ofV s = 1 V (V eff = 0.707 V) in order to maintain the modulation depth or deviation indicated. A monitoringcircuit checks the input voltage in the frequency range 10 Hz to 100 kHz. Deviations of more than ±3 %are signaled in the status line by means of the following messages (cf. Table 2-2). The inputs EXT1 andEXT2 can be AC- or DC-coupled. Monitoring is only active if the inputs are AC-coupled.Table 2-2MessageEXT1-HIGHEXT1-LOWEXT2-HIGHEXT2-LOWEXT-HI/HIEXT-LO/LOEXT-HI/LOEXT-LO/HIStatus messages in the case of a deviation from the rated value at the external modulationinputs EXT1 and EXT2DeviationVoltage at EXT1 too highVoltage at EXT1 too lowVoltage at EXT2 too highVoltage at EXT2 too lowVoltage at EXT1 and EXT2 too highVoltage at EXT1 and EXT2 too lowVoltage at EXT1 too high and EXT2 too lowVoltage at EXT1 too low and EXT2 too highFREQ250. 000 000 0 MHz LEVEL - 10.0dBmAMEXT1-LOWFREQUENCYLEVELANALOG MODVECTOR MODDIGITAL MODDIGITAL STDLF OUTPUTSWEEPLISTMEM SEQUTILITIESAMBB-AMFMPMPULSEAM DEPTHAM SOURCE INTAM SOURCE EXTAM EXT COUPLINGLFGEN FREQ30.0 %OFF INTOFF EXT1AC DC1.000 0 kHzFig. 2-24Example: Status message "EXT1-LOW" in case of voltage at EXT1 too lowI/Q InputsThe nominal voltage at the I/Q-inputs for external vector modulation is U s = 0.5 V. Input resistance is50 Ω. For a more detailed description, cf. Section "Vector Modulation".For external broadband AM the I-input is used. Input sensitivity is 0,25 V for 100% AM.1125.5555.03 2.56E-8