Circuit Classics: Bargraph Voltage Indicator

This amazing circuit offers you a chance to become a real scientist and engineer. It's a significant milestone as you use tools you've built on your own. With your self - made voltmeter, you can measure batteries or explore other electronic circuits in the real world. Forrest M. Mims III is a well - respected figure in the electronics field. His engaging texts have introduced millions to electronics. I've brought three of his hand - drawn circuit projects to life with these finely - crafted Circuit Classics boards. They make an ideal gift for beginners, expert tinkerers, or just a cool item for your desk. The kit includes a Bargraph Voltage Indicator PCB, an Alcohol Prep Pad, a Battery Clip, an LM393N Integrated Circuit, eight 1kΩ Resistors, a 100kΩ Potentiometer, four White LEDs, a Black Alligator Clip, a Red Alligator Clip, a White Alligator Clip, four Rubber Feet, and a Wooden Stand. To assemble the kit, you'll need a soldering iron and solder. You can use the wooden stand or a 'third hands' to hold the board. Batteries aren't included, and you can choose different ways to power it. When assembling, start with short components and be careful when inserting the chip. After assembly, test the circuit and you can use it to measure various voltages and conduct experiments.

Hey there! Using this Bargraph Voltage Indicator is super fun. First, gather your soldering iron and solder. The kit comes with most things you need, but not batteries. You can pick the way to power it, like using alligator clips or the battery clip on the back. When you're assembling, start with the short, flat components like the 1k resistors. Use the wooden stand to hold the board at a good angle. Be really careful when inserting the LM339 chip; make sure the notch on the chip lines up with the one on the board. After you're done soldering, power it up. If you built it right, all four LEDs should light up when you're not using the white alligator clip to measure voltage. You can test the circuit by measuring at the gold test points on the left - hand side of the board. The potentiometer knob can adjust the circuit's sensitivity. When you experiment, you can use the white alligator clip to measure the test points on the board. Remember, only measure voltages lower than the power source you're using, and don't use anything over 9V to power the indicator. For maintenance, you can use the alcohol prep pad to clean the solder flux a bit. You can also put the rubber feet on the board or the bottom of the wooden stand for better display and grip.