What are the differences between wave generator and oscillator? (Specific design)

itayd100

Joined Jan 30, 2016
3
Hello,

I design the attached circuit:
75 MHz Sine wave that connected to R and C in parallel

The output, the amplitude of the sine wave, is changing according to the C, more capacitance smaller amplitude of the sine wave.

When I tried that in the lab I got 2 results:
1. When I connected the signal generator as an oscillator I got the same results - higher C lower amplitude (of the sine wave in the output)
2. When I connected it to oscillator (http://www.farnell.com/datasheets/75480.pdf) I'm getting different result: the output is a sine wave, but if I make C higher the amplitude becoming lower until the sine wave (in the output) is "flipping" (kind of changing phase) and, if I keeping the C higher, the sine wave in the output getting higher

What are the differences between the two?
How can I make the oscillator work like the wave generator in this case?

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Dodgydave

Joined Jun 22, 2012
10,964
Its called Reactance, as the frequency changes the capacitor acts like a resistor in parallel and as the frequency increases its reactance gets lower, viceversa so it attenuates the signal.

itayd100

Joined Jan 30, 2016
3
Its called Reactance, as the frequency changes the capacitor acts like a resistor in parallel and as the frequency increases its reactance gets lower, viceversa so it attenuates the signal.
Hey,
thanks for the answer. I know that called reactance, but why with the two setups I'm getting deference results? (same frequency, came C, same R)

dl324

Joined Mar 30, 2015
15,838
What is the other setup?

You mentioned trying this in a lab. Is this homework?