One time I read an Nuts and volts article where this guy took a usb cord and unhooked the +5v(red wire) and made it where the arduino can be powered by an external power supply without breaking anything.. This can be also handy for power hungry devices(such as external dvd burners,etc). This will draw nothing […]
When an soundcard probe uses wrong polarity on android/chromebooks
In this blog I will review the Virtins Soundcard probe using it on a chromebook. Chromebooks use a 4-pin headphone not a 3-pin connector like PCs and regular laptops use. Here comes the interesting part when measuring a sawtooth wave it was going backwords seen on figure 1 What can that do to the circuit? […]
0-30v/0-60v dual power supply
Here’s a type of powersupply you should have. It’s good if you’re dealing with OP amps. I took the circuit from eleccircuit.com and modified it to incorporate 2x printer power supplies instead of an AC transformer. It provides a ground that are both positive and negative. LM317 and LM337 regulators are utilized in this circuit. […]
Pythagorean Transistor Circuit
Here’s a circuit that Joerg from the electronics chat shared with me. The circuit outputs a current and inputs a current for the variables in the Pythagorean equation. Pythagorean theorem solves for the hypotenuse of a triangle. The currents in the circuit are the same way where C is the hypotenuse in amps I(A) is […]
Fake Flash Drive Tester
This script simply creates files onto the flashdrive to see if it is a real flash drive or fake. All files created by this script should all be the same. It works with all OSes that support PHP. NOTE THIS TOOL IS NOT MADE TO BE USED FROM A WEB SERVER. Batch file is included […]
Audio over telephone
Heres a simple circuit that takes a audio signal(from ham radios,computers or cd players) and converts them into a telephone signal. It powers the phone line with 22vdc(It doesn’t have to be 22vdc, different voltage means different resistor is needed). The phones can run as high as 48v. If you use cordless phones the converter […]
mIRCSMS text message bnc
Textbelt bouncer plugin for mIRC Chat client This is a plugin that lets you access IRC over texting. I wanted something for my phone that I would not having to open a app everytime my phone starts. System Requirements For compiling you will need Delphi 4.0 with TmIRCControl A Textbelt API Key(you will have to […]
DIY cable tester
In this blog I will show you two ways to make a cable tester. The 1st way uses a arduino (software controlled). The 2nd way uses a decade counter chip(CD4017) and a flashing LED. I am going to order the Dual RJ45 jack to screw terminals from eBay. The other connectors are from parts-express. I […]
6AL5 low voltage logic circuit
In this blog we will experiment with vacuum tube logic gates. We will be using low voltage so it is totally safe. We will use a 6al5 twin diode tube. In the circuit below shows how to use it as semiconductors diodes but it’s very same as for vacuum tubes. Simply wire positive and negative […]
Capacitance substitution board
In this blog I will show you how to make a dip switches capacitor substitution board. Its very simple since capacitors add up in parallel. So if you look at the schematic you will get an idea.
Circuit Simulator