N5161A/62A/81A/82A/83A MXG Signal Generators User's Guide

Basic Digital Operation (Option 651/652/654)Setting the Baseband Frequency OffsetModulated carrier with 0 Hzbaseband frequency offsetModulated carrier with 20 MHzbaseband frequency offsetModulated RF signalLO/carrier feedthroughSpectrum analyzer set to a span of 100 MHzDAC Over–Range Conditions and ScalingWhen using the baseband frequency offset (at a setting other than 0 Hz), it is possible to create aDAC over–range condition, which causes the Agilent MXG to generate an error. To minimize thiscondition with the frequency offset feature, the Agilent MXG incorporates an automatic DACover–range protection feature that scales down the I/Q data by 1/square root of 2 when the offset issomething other than zero. Because it can scale the data by more than what is actually need, ittypically decreases the dynamic range of the waveform. This is especially noticeable when using aconstant amplitude signal such as GSM.For the Dual ARB Player, this automatic over–range feature can be turned off. When on, it is activefor the Dual ARB signal only when the offset is something other than 0 Hz. The control for the DualARB DAC over–range protection feature is located in the key path as shown in Figure 8- 14.196 Agilent N5161A/62A/81A/82A/83A MXG Signal Generators User’s Guide