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When you cannot get an oscilloscope probe into a tight spot, can you just use a piece of wire? Sometimes. When signal integrity matters, you CAN use a low-cost DIY solder-in probe. These probes attenuate the signal and use an oscilloscope’s high-bandwidth 50-ohm input. James shows how to build some solder-in probes when they work and when they do not work in this video.

Special thanks to Shabaz on the element14 community for the guide used here.

Vector network analyzers (VNAs) measure how a “network” of components changes the amplitude and phase of signals. By measuring across a wide frequency range, VNAs can create S-Parameters that fully describe the behavior of a circuit. This video uses a PicoVNA 106 to show the basics of what a VNA measures, how they work, and a brief overview of how to use one.

I made a mistake on the explainer graphic for S-parameters. The annoying thing is that I think it was a really good explanation!

Compare the ideal and measured cut-off frequency for a filter with a handheld LCR meter. Unlike a DMM, these meters apply an AC signal (from 100 Hz to 100 kHz) to determine the reactive component of an inductor, capacitor, or resistor. A simple example here is a low-pass filter. See how the ideal and measured cut-off frequency varies. And THEN, see how it compares between a PCB and a Breadboard.

This episode was sponsored by Multicomp Pro

Source Measurement Units, or SMUs, combine an accurate power supply, high-power electronic load, and precise digital voltmeter into a signal unit. They are a four-quadrant source. That means they can provide power to a circuit or consume it.

With an SMU you can characterize semiconductor devices (like Diodes), monitor the power consumption of a circuit, or simulate a battery. In this video, see the difference between an SMU and a Power Supply.

This episode was sponsored by Rohde & Schwarz.