Archive for the ‘Circuits’ Category

mark_of_the_beast_RFID_right_hand
Above, an RFID chip is implanted into the right hand.
Continue reading ‘RFID Wristbands – One Step Closer to the Mark of the Beast’ »

robot-breathing-fire

Will robots take over the world?  If robots rise up, will they keep people around in zoos?  There is hope.  Watch the video for details.
Continue reading ‘People Zoo’ »

Edison, in 1877, made the first recording on his tinfoil phonograph. He recorded “Mary Had a Little Lamb”.
Continue reading ‘First Audio Recording Ever by Thomas Edison’ »

Joule_Thief_Gift

Continue reading ‘Joule Thief Gift’ »

HexBug Inchworm, Micro Robotic Creatures, Review

Review of HexBug Inchworm by Micro Robotic Creatures

Continue reading ‘HexBug Inchworm ~ Micro Robotic Creatures ~ Review’ »

smoke-alarm-on-wall

Do smoke alarms cause cancer?

Continue reading ‘Radioactive Smoke Alarms’ »

This is an experiment generating electricity from scrap metal.

Scrap CRT TV lying on the ground produces electricity as it rusts.

Scrap CRT TV lying on the ground produces electricity as it rusts.

Continue reading ‘Scrap Metal Power’ »

Made my 2nd Joule Thief today, a little different than the first one.

A rubber band secures the battery to the Joule Thief.

A rubber band secures the battery to the Joule Thief.

Continue reading ‘Rubber Band Joule Thief’ »

Bluetooth wireless transmitter connected to a Nokia N810 Internet Tablet

Bluetooth wireless transmitter connected to a Nokia N810 Internet Tablet

Looking for a bluetooth transmitter?  This one might be good for you.

I enjoy listening to podcasts using my N810 Internet Tablet and my bluetooth headphones (Creative CB2530 wireless headphones).  To use bluetooth headphones, you will need a bluetooth transmitter connected to the source, in my case connected to the N810 tablet. This post is a review of the bluetooth transmitter and some tips on how to repair one of its failure modes.

Continue reading ‘Bluetooth Transmitter Review and Repair’ »

My car started giving me all kinds of electrical problems.  I popped the hood and found a nest!

nest-in-engine-compartment

Read on to see how a small animal caused electrical trouble for this car.

Continue reading ‘Nest in My Car’s Engine Compartment!’ »

Maximum voltage achieved with my Joule Thief was 20.5V.

Maximum voltage achieved on the Joule Thief's output was 20.5V.

Continue reading ‘Joule Thief and Capacitors’ »

Blue LED pumping out light while powered by Joule Thief.

Blue LED pumping out light while powered by Joule Thief.

Continue reading ‘Joule Thief Powers ANY Color LED’ »

Handmade Toroidal Inductor

Handmade Toroidal Inductor

How does the number of turns in the toroidal inductor affect the performance of a Joule Thief?

Continue reading ‘Toroidal Inductors – Number of Turns Affects Joule Thief’ »

Handmade toroidal inductor for "Joule Thief" circuit.

Handmade toroidal inductor for "Joule Thief" circuit.

To make one of these, you need to start with a toroid, which is a piece of ferrite (Iron) shaped like a doughnut. You will also need wire. I used 0.3mm coated copper wire.

Continue reading ‘Handmade Toroidal Inductor’ »

A "Joule Thief" or Voltage Booster powering 2 white LED's with a single, "dead" AA battery

My first "Joule Thief" powering 2 white LED's with a single, "dead" AA battery

I’ve been wanting to do this for many months.  I finally got some scrap parts together and made my first Joule Thief.  This circuit milks the last bits of energy out of your “dead” batteries.

Circuit diagram, video, pictures, and observations included…

Continue reading ‘Joule Thief from Scrap Parts’ »

I tried making the Joule Thief as shown in a Make video from makezine.com.

makezine.com and evilmadscientist.com

makezine.com and evilmadscientist.com

The results were not as expected, but I found a variation of the Joule Thief circuit that worked better for me.  I share some of the results with you in this post.

Continue reading ‘Joule Thief from Make Video Doesn’t Work for Me’ »

Neodymium-Magnets_and_button_cell_batteries

Neodymium Magnets and Coin Cell Batteries. These are used to power up a TI Launchpad MSP430.

Video included.

Continue reading ‘MSP430 Tricks with LED’s, Capacitors, and Neodymium Magnets’ »

power-use-msp430-ti-launchpad

Want to know how much power the MSP430 uses?  I show a way to reduce the power consumption of the Launchpad by 97%.  Read on and see the video.

Continue reading ‘How Much Power Does MSP430 / TI Launchpad Use?’ »

When driving LED’s with a microcontroller, chances are you won’t have enough power coming out of the microcontroller’s pins to power an LED. For example, the TI Launchpad MSP430 only allows for a reliable 1.5mA of power out of each pin. To drive an LED, you might want more like 20mA. So you will need an external circuit to safely drive the LED.

Circuit I used to drive an LED with TI Launchpad MSP430.

Circuit I used to drive an LED with TI Launchpad MSP430.

Read on and see the video.

Continue reading ‘Calculate Resistor Values for Driving LED’s’ »

calculate-forward-voltage-of-LEDs-red

It is simple to measure the forward voltage of an LED.  You just need an appropriate choice of battery and resistor.  Read on and see the video…

Continue reading ‘Calculate LED Forward Voltage’ »

I noticed my ground connection outside was cut, so I reconnected it and saw an improvement to the TV signal.

I noticed my ground connection outside was cut, so I reconnected it and saw an improvement to the TV signal.

Video follows…

Continue reading ‘Cable TV Signal Improved by Ground’ »

scrap-electronics

If you have a broken TV, there are lots of electronics inside you might want to keep.

Continue reading ‘Salvaging electronics from a broken TV’ »

A couple different adapters plugged into a 12V battery

A couple different adapters plugged into a 12V battery

My USB adapter quit working. I opened it up to see what the circuit looks like and determine what caused it to fail.

Also shown: Charging a cell phone with a wind turbine.

Continue reading ‘USB Adapter Repair – 12V to 5V Voltage Regulator’ »

Review of a 12V splitter.  This is also called a 3-way cigarette lighter adapter .

12V adapter-splitter review

12V adapter-splitter review

This adapter plugs into a single 12V battery outlet and splits it into three outlets.  Could be used to power three gadgets from your car or from wherever else you have a 12V outlet.  I have one in my house for off-the-grid backup power.

Video review…

Continue reading ‘12V Three-Way Adapter’ »