DVM usually got an input impedance of 10 Mohm. There may be loading effect when measuring high impedance circuit.
数字式电压表通常有10兆欧的输入阻抗。当测量高阻抗电路时﹐可能会有影响。
2
X1 probe: no attenuation, input impedance follow that of scope input impedance (usually 1 Mohm). This type of probe is seldom used because of heavy loading effect on circuit under test.