April 17, 2024, at 1:00 pm CDT
Capacitors are deceptively complex devices. It is why I love talking about them so much! Hioki USA loaned me an LCR Meter that works as an Impedance Analyzer to try out some measurements. As a result, I noted a few things that might catch someone off guard if they have never attempted to characterize capacitors.
Whether you are just getting started in electronics or you have boxes of parts, it is good to know what are the most critical parts to have in your kit. James asked the element 14 community for what they considered to be essential passive components like resistors, capacitors, switches, wires, and even diodes. In this video, he consolidated their puts and explains what to think about when buying these parts for your kit.
Learn how to use an LCR meter, such as the Tenma 72-10465, to measure reactive components. An LCR meter uses an AC signal at different frequencies to characterize capacitors, inductors, and even resistors. They can also provide impedance measurements. These include phase angle, ESR, quality factor, and dissipation factor.
You can even use the 72-10465 to sort components by their tolerance range.
A question came up on IRC regarding how to PWM a 3-pin PC fan with an Arduino using analogWrite(). Controlling the fan was seemingly straightforward. The problem was that the hall effect sensor, or TACH signal, was incredibly noisy. The noise made it impossible to measure the fan’s rotation. Working through the question, I found three issues to tackle:
- You need to use a PNP transistor
- Filter capacitors help
- Create a non-blocking RPM measurement (with millis())
This post addresses all three issues regarding how to PWM a 3-pin PC fan with an Arduino.