Rigol RP6150A Oscilloscope 1.5 GHz Passive Low Resistance Probe

For digital oscilloscopes, the signal under test needs to be connected to the measurement channel via various oscilloscope probes or 50 ohm cables. The Probing is very important to making quality measurements. If the probe performance is not adequate or if you did not select the proper probe for your application, you will see distorted or misleading signals on your oscilloscope.

There are two kinds of probes, one is passive probe, another one is active probe. active probe requires power while passive probe does not. For general-purpose measurements(<600MHz), passive high-impedance resistor divider probes are good choices in general. For high-frequency applications (>600 MHz), active probes are the way to go. They cost more than passive probe and their input voltage is limited, but because of their significantly lower capacitive loading, they give you more accurate insight into fast signals.