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Function Generator Question
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tkgmomosheep:
I recently acquired a second hand function generator DG3121A, I tried the built-in self-test and it passed.
But I am having trouble using the modulation function.
I am using a DS1054Z(hacked) to see the generator output with and without 50ohm termination(using the high impedance mode and manually set the output to 50ohm), but doesn't seem to be able to see any modulation at all.
Below are the images of the test setup.
Please let me know if it's my fault or the generator is not working properly.
Thank you!

https://imgur.com/a/H6pPBOb
Brumby:
At 1 microsecond per division, you are not going to see the modulation (you are only looking at 0.18% of the modulation waveform).  Don't be fooled by the image presented on the function gen.  It's only representative.  To see the 150 Hz modulation, the 2.5 MHz carrier will become a fuzzy haze.

Slow down your timebase.  Try 1ms per division or even slower.
tkgmomosheep:
Thanks for the reply!
I tried it with a 1ms and the images are attached in the link.
https://imgur.com/a/SwFHf2B
I am also wondering why the Vpp will drop significantly no matter what AM depth I set it to.
Actually I wanted to try out the intensity gradient display of the oscilloscope with an AM signal.
Would you mind telling me how to set the scope and the generator up the connection required?
HB9EVI:
Obviously you set the carrier on 2,5kHz not 2,5MHz

to see the intensity gradient, you have to go much higher than 2,5kHz for the carrier
tkgmomosheep:
I tried with a much higher carrier fruquency at 1Mhz and modulate it with 1khz 100%.
But still not the result I was expecting.
I tried both Normal and HighRes mode and both yielded similar result.
https://imgur.com/a/ASeXw2o
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