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.
Pull-up and Pull-down resistors explained
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Category Archives: Electronics
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.
Coax cable options
Today I got myself two of these RG316 coaxial cables. Other choices were RG58 and RG174 options. I found this discussion on reddit which suggested that for my application (connecting my bench scope to circuits for testing) any of them will probably do. I got two 4 meter cables, so when I cut them in half I will have four 2 meter cables.
The United States Frequency Allocation Chart
Some notes about how spectrum is allocated in the USA: The United States Frequency Allocation Chart
I must, must, must not get involved in radio. I would love to, but I don’t have enough time or money! Gotta stay digital… :P
Anatomy of a cheap USB to Ethernet adapter
An interesting write up concerning a shanzhai knock off: Anatomy of a cheap USB to Ethernet adapter.
Bipolar Junction NPN and PNP transistors
I have attached some notes about bipolar junction NPN and PNP transistors.
300in1 Project 155. DTL OR GATE
So I did a circuit. This is a diode/transistor logical OR gate. I’m learning. What I’d like to understand is why the resistors are necessary and why are the resistor values picked such as they are? I’ve asked a question about this over on the EEVblog: What is the purpose of the resistors in this schematic?.
Saving an SSD
This is awesome. This bloke diagnosed and fixed a problem with an SSD drive: Crucial SSD Drive Failed – Can we save data.?
I found the thermal imager used in the video on his website: UNI-T UTI260B Thermal Imager Camera 256px x 192px. Definitely want to get myself one of those!
Custom 2.5-inch IDE SSD Assembly and Testing
This video is awesome. This guy built his own SSD! Custom 2.5-inch IDE SSD Assembly and Testing