Quantcast
Channel: voltage – Hackaday
Browsing all 26 articles
Browse latest View live

Image may be NSFW.
Clik here to view.

Tube amp monitor

Sparkfun contributor [Pete] really loves tube amps, but he’s a very safety-conscious guy who doesn’t like being electrocuted. This is a problem, since tube amps are usually very high voltage, and a...

View Article



Image may be NSFW.
Clik here to view.

LED battery level indicator

[Kc7fys] came up with a this simple battery level indicator. It uses a single LED to display a battery’s voltage; if the voltage exceeds 12V, it glows green. If it is below 11V, the LED glows red....

View Article

Image may be NSFW.
Clik here to view.

PIC programmable power supply

This programmable power supply is the perfect addition to your bench tools. [Debraj Deb], who previously built a whole house power monitor, designed this build around a PIC 18F4520 microcontroller....

View Article

Image may be NSFW.
Clik here to view.

Adjustable voltage and polarity tester

Instructables user [Rudolf] wrote in to share a handy little tool he created with ham radio operators in mind. Now and again, he found himself connecting to an unknown power supply, and rather than...

View Article

Image may be NSFW.
Clik here to view.

Automotive battery voltage monitor

[Rajendra’s] car had just about all the bells, whistles, and gauges he could dream of, but he thought it was missing one important item. In an age where cars are heavily reliant on intricate...

View Article


Image may be NSFW.
Clik here to view.

Light bulb, diode, and capacitor step mains down to 12V DC

[Todd Harrison] needed a way to run a 12 volt PC fan from mains voltage. Well, we think he really just needed something to keep him occupied on a Sunday, but that’s beside the point. He shows us how...

View Article

Image may be NSFW.
Clik here to view.

From the readers: low battery cutoff solutions

We got a lot of really great feedback about low battery cutoff options in the comments section of Monday’s replacement battery post. To refresh your memory, some power tool batteries were replaced by...

View Article

Image may be NSFW.
Clik here to view.

AC vs DC human pain test

Ever wondered just how much being zapped by electricity hurts? Curious if AC is worse than DC? Want to know just how many volts a human body can take? Although many people might cringe at the shear...

View Article


Image may be NSFW.
Clik here to view.

Afroman Demonstrates Boost Converters

If you need to regulate your power input down to a reasonable voltage for a project, you reach for a switching regulator, or failing that, an inefficient linear regulator. What if you need to boost the...

View Article


Image may be NSFW.
Clik here to view.

Adding a Battery Gauge to a Project With Zero Parts

The typical way of doing a low battery detector is throwing a comparator in the circuit, setting it to measure a certain threshold voltage, and sending that signal off to a microcontroller or other...

View Article

Image may be NSFW.
Clik here to view.

“Who is John Galt?” Finally Answered

For those who haven’t read [Ayn Rand’s] philosophical tome Atlas Shrugged, there’s a pretty cool piece of engineering stuffed in between the 100-page-long monologues. Although fictional, a character...

View Article

Image may be NSFW.
Clik here to view.

Isolated Voltage Measurements Through Frequency

This one’s not a flashy hack, it’s a great piece of work and a good trick to have up your sleeve. Sometimes you’ve got a voltage difference that you’d like to measure, but either the ground potential...

View Article

Image may be NSFW.
Clik here to view.

Building Transistors with Transistors

Since the 1940s when the first transistor was created, transistors have evolved from ornery blocks of germanium wrangled into basic amplifiers into thousands and thousands of different devices made of...

View Article


Image may be NSFW.
Clik here to view.

Say It With Me: Root-Mean-Square

If you measure a DC voltage, and want to get some idea of how “big” it is over time, it’s pretty easy: just take a number of measurements and take the average. If you’re interested in the average power...

View Article

Lightning Generator from Electric Lighter

Generating high voltages isn’t too hard. A decent transformer will easily get you into the 100s of kilovolts, provided you’re a power company and have access to millions of dollars and a substation to...

View Article


Custom Circuit Makes for Better Battery Level Display

Isn’t it always the way? There’s a circuit right out of the textbooks, or even a chip designed to do exactly what you want — almost exactly. It’s 80% perfect for your application, and rather than...

View Article

Old Wattmeter Uses Magnetics To Do the Math

Measuring power transfer through a circuit seems a simple task. Measure the current and voltage, do a little math courtesy of [Joule] and [Ohm], and you’ve got your answer. But what if you want to...

View Article


You Didn’t See Graphite Around This Geiger Counter

Even if you don’t work in a nuclear power plant, you might still want to use a Geiger counter simply out of curiosity. It turns out that there are a lot of things around which emit ionizing radiation...

View Article

Image may be NSFW.
Clik here to view.

Five Channel Monitor Keeps Boat Batteries Shipshape

While those of us stuck sailing desks might not be able to truly appreciate the problem, [Timo Birnschein] was tired of finding that some of the batteries aboard his boat had gone flat. He wanted some...

View Article

Image may be NSFW.
Clik here to view.

If You Need a Measurement Tool Just Build A Measurement Tool

[Darlan Johnson] was working on a wearable project and needed a way to measure the change in voltage and current over time.  Most measurement tools are designed to take snapshots of a system’s state in...

View Article
Browsing all 26 articles
Browse latest View live




Latest Images