I have been using my PCSGU250 about 3 times a week since i bought it in DEC09.
It has been an excellent addition to my lab, but I have some concerns about results I have seen during an experiment I have been running.
I attempted to perform a measurement on a RL circuit with total impedance of 1kOhm at DC. I ran the function generator at 1.00Vrms but noticed that as my frequency increased, the source voltage did not stay constant, and would experience considerable droop over the AC sweep I performed. The amplitude at 1Mhz did not equal the amplitude at 100Hz. I removed all circuit elements, and measured only the function generator with CH1 and Ch2. I have noticed two things:
1 At 10Vpp with dc offset set to 0 on the FuncGen, Ch1 max reads 4.56/min is -4.66 , Ch2 max reads 4.31min is -4.50
Shouldn’t this read -5/+5 for both?
- As frequency increases, droop occurs and the disparity increases between the source voltage and what it should be according to settings. The drop can be anywhere from a few hundredths of a volt to 2 or 3 volts when attempting to use 10Vpp with a sine source and a 1kOhm load.
Calibration was attempted to fix the issue, but did not produce successful results.
What are the frequency characteristics of the function generator under load? Am I overloading the system by using too small a system impedance?
