I have an Agilent 33500 Series Arbitrary Waveform Generator and created few waveforms (such as sine, ramp, trap, etc.) using the Agilent Benchlink Waveform Creator software. My question is, how come the ouput voltages are doubled although the waveforms I created doesn't show that. The output is going to a demodulator and signal conditioner.
This assumes a waveform with a 2V P-P signal.
If the AFG output impedance is set to 50 ohms before sending the waveform to the AFG, but the actual load is HiZ (scope) the AFG o/p signal will appear as 2x (4V P-P).
Adding a 50 ohm load to match the AFG o/p impedance will reduce the signal level to the expected and correct level of 2V P-P.
If the AFG o/p is set to HiZ, before sending the waveform to the AFG, and the actual load is HiZ, the signal will be appear correctly as 2V P-P.
It seems either the AFG or the waveform editor read the AFG o/p impedance setting and adjust the AFG to present the correct o/p value based on the selected AFG o/p impedance.
Bottom line. Match the AFG o/p impedance to the target load.\
Regards,
Jim