Vpp question

I've got good money here that says you are not properly terminated. Most generators I've seen from audio to RF are designed to operate into a specified impedance, it's usually written on the generator. Does it say 50 ohm out? Then the generator "expects" to be connected to a nice 50 ohm environment. The scope on the other hand usually has a 1M (megohm) input. Sometimes scopes have a 50 ohm input position but be very careful not to exceed the scope's input voltage rating in this case. Usually they don't handle much more than 5V RMS.

Or if you're using an "audio" generator it might want a 600 ohm load.

Is the generator expecting a 50 ohm load? If so, the output will be double the setting into a high impedance load.

Your generator is expecting a 50 Ohm load. Some modern generators allow you to set the display amplitude mode: terminated or not.

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Mark

As others have said, the sig gen is expecting a 50-ohm terminator on the other end of the cable.

If your scope doesn't have a "50 ohm" setting, you could get one of these:

If you're just doing low frequency stuff, you're probably OK without the 50 ohm terminator, you just need to remember your setting is off by a factor of 2. But as you approach RF frequencies ***, you'll get weird wave-interference effects in your cabling, and the output amplitude will vary with frequency.

Regards,

Mark

*** problems happen at frequencies where the signal's wavelength (in the cable) is comparable or less than the cable length. You're okay if the wavelength is a lot longer than the cable length:

Wavelength >> Cable or (Signal velocity)/frequency >> Cable or Frequency