The characteristics of a 10:1 attenuation...

🔍 Key Concepts

• How a 10:1 oscilloscope probe changes the input resistance seen by the circuit compared to a normal 1:1 (direct) connection • The typical input resistance and input capacitance of a standard oscilloscope vertical input (no probe) • Why attenuation probes often include a compensating capacitor instead of an inductor

💭 Think About

• First, recall the usual input resistance of a standard scope channel and then determine what the probe must do to create a 10:1 voltage divider with that resistance. • Think about whether attenuation probes are normally designed to look mostly resistive or inductive/capacitive at the frequencies of interest, and which component values are realistic for that purpose. • Compare the given resistance and reactance values: which combinations would form a practical 10:1 divider while maintaining good high-frequency response?

✅ Before You Answer

• Verify what a typical oscilloscope input resistance is (commonly around a specific megohm value). • Check whether an attenuation probe more commonly uses a small capacitor in parallel with its resistance, or a relatively large inductor like several millihenries. • Confirm which answer choices give an overall probe input resistance about 10 times the usual scope input resistance and a small picofarad-range capacitance rather than a large inductance.

The characteristics of a 10:1 attenuation probe for an oscilloscope is as follows:

A load of about 10 megohms shunted by 12 pF.

A load of about 20 megohms shunted by a 12 mH coil.

A load of about 5 megohms shunted by 6 pF.

A load of about 5 megohms shunted by a 6 mH coil.

🔍 Key Concepts

💭 Think About

✅ Before You Answer