- #1
H_man
- 145
- 0
Hi all,
I've noted for years that oscilloscope probes tend to pick up noise from AC power cables, but just recently I tried connecting an antenna (piece of wire) to the probe and placing it near some power cables and voltage recorded was off the scale.
I have calculated that the power radiated from a few meters of normal everyday cable with say an amp or two flowing at 50 Hz should be of the order of 10^-10 Watts, so what is the probe picking up? After all, if I'm not mistaken to build a resonant circuit at 50 Hz you either need a lot capacitance or a lot of inductance and I don't think the probe is big enough to contain either relatively large components.
Anyone dealt with this before in any detail?
Thanks
Harry
I've noted for years that oscilloscope probes tend to pick up noise from AC power cables, but just recently I tried connecting an antenna (piece of wire) to the probe and placing it near some power cables and voltage recorded was off the scale.
I have calculated that the power radiated from a few meters of normal everyday cable with say an amp or two flowing at 50 Hz should be of the order of 10^-10 Watts, so what is the probe picking up? After all, if I'm not mistaken to build a resonant circuit at 50 Hz you either need a lot capacitance or a lot of inductance and I don't think the probe is big enough to contain either relatively large components.
Anyone dealt with this before in any detail?
Thanks
Harry