Watched a video about how to implement a mains indicator: Using LEDs as mains indicator lights on 120V and 230V (live demos).
Using LEDs as mains indicator lights on 120V and 230V
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Category Archives: Electronics
DC-580 buck-boost power supply with CH340N IC
Universal Magnetic Car Phone Holder
I found these cool magnets: Universal Magnetic Car Phone Holder Dashboard Hands-Free Mobile GPS Mount Stand. I didn’t buy any, but I might!
And speaking of magnetic material I should get, these look cool too: A4 Magnet Sheets Black Magnetic Mats for Refrigerator Photo and Picture Cutting Die Craft Magnets Magnetic on One Side 0.5mm.
The NanoVNA, a beginners guide to the Vector Network Analyzer
Found this great video: The NanoVNA, a beginners guide to the Vector Network Analyzer. Good links in the description. My mate Raz says to get NanoVNAs from either here or here.
Dielectric loss
Some light reading: Dielectric loss.
Progress
Today is the first day I have used my signal generator, my scope, and a breadboarded circuit, at the same time. Used my multi-meter with its new cables too!
Thanks to my friend Raz for his help. <3
Frequency response
So I pumped a 1 kHz square wave into my DTL OR gate and observed the behaviour with my scope!
The square wave is in yellow, and the blue is the output signal.
You can see the output doesn’t drop back to zero quite as fast as the input.
You can see on the multi-meter to the right that the current draw is about 5.83 mA. That’s consistent with my earlier measurements given a duty cycle of 50%.
And you can see in the following photo that the frequency response of the circuit is rubbish. If you go much above about 10 kHz the output just stays “on”.
Pull-up and Pull-down resistors explained
I found a good article explaining how pull-{up,down} resistors work and how to calculate appropriate values: Pull-up Resistors and Pull-down Resistors Explained.
Current measurements
So I used my new cables in anger. I took a reading of the current draw on 300in1 project 155 that I was working on the other day. Will be able to experiment with the effect of using different resistors (and none at all).
Multi-meter cables
Made some cables. Male banana plug into male jumper wire. Got some of these and cut them. Made a pair of long ones and two pairs of short ones. This is so I can plug my multi-meters into my breadboards. Gonna do the same thing with some BNC attached coax so I can hook up my scope and with some female DuPont cables so I can plug into male pin headers.
