Can the Model 625A signal generator generate digital QAM signals?
It depends on your constellation. If you desire to generate MPSK, then one unit can provide a baseband modulating signal to another that is operating in external phase modulation mode. If your QAM constellation involves amplitude and phase modulation, then you can use two units locked together; one generates the I baseband channel and the other generates the Q baseband channel. You would then need to feed these two signals to a quadrature modulator (external).
