I uploaded a video to YouTube specifically to help me explain my question. Please watch it if you can.
Otherwise, here is my text-based description:
- I have an oscilloscope, function generator and multimeter.
- The function generator has an RCA cable outputting a simple 100Hz sine wave at 5V amplitude.
- The oscilloscope probe is on 10x and configured properly.
- When I connect the probe ground (earth mains ground) to ground of RCA and touch probe to center of RCA, I get exactly what I expected; a 100Hz ~5V signal on the scope. Cool.
- If I remove the probe/earth ground from the RCA cable and only probe the tip of the RCA directly, my scope shows 100 volts AC.
- I tested the AC voltage between the scope probe ground and the function generator RCA cable with my multimeter to confirm and I get 48 volts AC whether I touch the center pin or 'ground' of the RCA cable.
Why is there such a high voltage between earth ground and the signal generator's output? Does this mean that if I were grounded (like by grabbing the house's ground rod) and touched the RCA cable I would get shocked with 48-100 volts AC?
What am I missing here?
My electronics knowledge is... intermediate I suppose? I just don't understand why I would be getting such high voltage between a tiny output signal from this RCA cable.
I really feel like touching that cable while being grounded should not electrocute me lol, but 48 to 100 volts AC? I'm not brave enough to play games. I really need to understand this.