Table of Content


Issue 1 Sept 2009 

Back of the Envelope Calculations 

  - 

Wind Energy Ship

Circuit Diagnosis

  - 

Exploding Capacitors

Dave's Rants & Raves

  - 

Electrodeless Fluorescent Lamps

Experimenter's Corner

  - 

Wireless Battery Charger

Good Idea done Badly

  - 

Bad Solar Powered Birdbath Design

What the World needs Now

  - 

Drinking Fountain from Pond Water

Wily Widget, the Lone Inventor

  - 

Wave Length Indicator

 

Issue 2 Oct 2009

Back of the Envelope Calculations

  - 

Shippable Energy Container

Circuit Diagnosis

  - 

Vapor Pumping

Dave Rants

  - 

Electrodeless Fluorescent Lamps

Experimenter's Corner

  - 

Light Powered Battery Charger

Good Idea done Badly

  - 

Bad Path Light Design

New Products, 2008

  - 

New Products, 2008

What the World needs Now

  - 

PIGEON SCARECROW

Wily Widget, the Lone Inventor

  - 

Fence Alarm

 

Issue 3 Nov 2009

Back of the Envelope Calculations

  - 

Supercapacitor Home Energy Storage Unit

Circuit Diagnosis

  - 

Connector Woes

Dave Rants

  - 

Hot Rock Geothermal Energy

Experimenter's Corner

  - 

NiMH Battery State of Charge Monitor

Good Idea done Badly

  - 

Bad Alarm Clock

New Products, 2008

  - 

New Products, 2008

What the World needs Now

  - 

Drinking Water from Thin Ai

Wily Widget, the Lone Inventor

  - 

Vertically Lifting Security Gate Power Source

 

Issue 4 Dec 2009 

Back of the Envelope Calculations

  - 

Aluminum Pop Can Energy Source

Circuit Diagnosis

  - 

Flaky Garage Door Opener

Dave Rants

  - 

Bad Chinese Capacitors

Experimenter's Corner

  - 

Magnetic Vehicle Motion Sensor

Good Idea done Badly

  - 

Bad Office Chair Wheels

New Products, 2009

  - 

New Products, 2009

What the World needs Now

  - 

Wind Power Monitoring Blimp

Wily Widget, the Lone Inventor

  - 

Fireplace Fizzle

 

Issue  5 Jan 2010

Back of the Envelope Calculations

  - 

Energy Savings Using Voltage Bucking Transformer

Circuit Diagnosis

  - 

Dirty PC Boards

Dave Rants

  - 

Yellowstone Might Explode

Experimenter's Corner

  - 

Measuring Low Value Resistors

Good Idea done Badly

  - 

Bad Computer Power Supplies

New Products, 2009

  - 

New Products, 2009

What the World needs Now

  - 

NiMH Battery Tester

Wily Widget, the Lone Inventor

  - 

Solar Powered Wireless Sensor

 

Issue 6 Feb 2010

Back of the Envelope Calculations

  - 

Long Life Solar Powered LED Light

Circuit Diagnosis

  - 

Motor Speed Controller

Dave Rants

  - 

Inventor Name Fraud

Experimenter's Corner

  - 

Long Range Motion Sensor

Good Idea done Badly

  - 

Disappearing Letters on Key Boards

New Products

  - 

New Products

What the World needs Now

  - 

Tritium Power Generator

Wily Widget, the Lone Inventor

  - 

Coin Operated Telescope

 

Issue 7 Mar 2010

Back of the Envelope Calculations

  - 

Back of the Envelope Calculations

Circuit Diagnosis

  - 

Wrong LED Wavelength

Dave Rants

  - 

Fading White LEDs

Experimenter's Corner

  - 

White LED Lifetime Tests

Good Idea done Badly

  - 

Another Bad LED Night Light

New Products

  -  

New Products

What the World needs Now

  - 

Long Lasting LED Night Light

Wily Widget, the Lone Inventor

  - 

High Power Flashing LED

 

Issue 8 Apr 2010

Circuit Diagnosis

  - 

PCB Fabrication Problems

Dave Rants

  - 

Strange Science

Experimenter's Corner

  - 

Charging Alkaline Batteries

Good Idea done Badly

  - 

Bad Fluorescent Night Light

New Products

  - 

New Products

What the World needs Now

  - 

Candle Flame Powered Battery Charger

Wily Widget, the Lone Inventor

  - 

Corona Monitor

 

Issue 9 May 2010

Back of the Envelope Calculations

  - 

Hydrogen Energy Storage

Circuit Diagnosis

  - 

Circuit Diagnosis

Dave Rants

  - 

Stiff Wires from China

Experimenter's Corner

  - 

X100 Scope Probe

Good Idea done Badly

  - 

Bad Throw Rug

New Products

  - 

New Products

What the World needs Now

  - 

Large Outdoor Thermometer

Wily Widget, the Lone Inventor

  - 

Earth Battery

 

Issue 11 July 2010

Back of the Envelope Calculations

  - 

Lifted Weight Energy Storage

Circuit Diagnosis

  - 

Cracked Solder Joints

Dave Rants

  - 

Dave's Pet Peeves

Experimenter's Corner

  - 

Earth Signals

Good Idea done Badly

  - 

Bad Rubber Mulch

What the World needs Now

  - 

External USB linked HD UPS

Wily Widget, the Lone Inventor

  - 

Medical Fluid Detector

 

Issue 12 Oct 2010

Circuit Diagnosis

  - 

Wrong Capacitor Selection

Experimenter's Corner

  - 

Low Power AM Transmitter

Good Idea done Badly

  - 

Solar Powered Car Vent

New Products, 2010

  - 

New Products, 2010

What the World needs Now

  - 

Hot Car Cooler

Wily Widget, the Lone Inventor

  - 

Musical Chairs

 

Issue 13 Nov 2010

Circuit Diagnosis

  - 

Conductive Adhesive Tape Problems

Experimenter's Corner

  - 

Flameless LED Candle Power Boost

Good Idea done Badly

  - 

Bad Carriage Bolts

What the World needs Now

  - 

Switch with Hysteresis

Wily Widget, the Lone Inventor

  - 

Restaurant Table Service Request Flasher

 

Issue 14 Dec 2010

Back of the Envelope Calculations

  - 

Charge Pump Paradox

Circuit Diagnosis

  - 

Temperature Sensitive MOSFET

Experimenter's Corner

  - 

High Voltage Ceramic Capacitors for Line Powered LEDs

Good Idea done Badly

  - 

Bad 40W Fluorescent Lamps

What the World needs Now

  - 

Bovine Calving Alarm

Wily Widget, the Lone Inventor

  - 

Water Well Pump Motor Indicator

 

Issue 15 Jan 2011

Back of the Envelope Calculations

  - 

Solar Energy Myth Busting I

Circuit Diagnosis

  - 

Reversed Battery Polarity

Experimenter's Corner

  - 

Optical Fiber Pressure & Motion Test Circuit

Good Idea done Badly

  - 

Bad AC to DC Wall Power Adapters

New Products, 2010

  - 

New Products, 2010

What the World needs Now

  - 

Miniature AC to DC Power Supply

Wily Widget, the Lone Inventor

  - 

Underground Gate Opener

 

Issue 16 Feb 2011

Back of the Envelope Calculations

  - 

Space Mirror for City Illumination

Circuit Diagnosis

  - 

Modulated Light Interference

Experimenter's Corner

  - 

Ultra Low Current Circuit Examples

Good Idea done Badly

  - 

Bark Off Ultrasonic Barking Dog Deterrent Device

New Products, 2010

  - 

New Products, 2010

What the World needs Now

  - 

Space Helmet for Yard Work

Wily Widget, the Lone Inventor

  - 

Buddhist Temple Statue Light

 

Issue 17 Mar 2011

Back of the Envelope Calculations

  - 

Off-Grid Home with Electric Car

Circuit Diagnosis

  - 

Schottky Diode Leakage Current

Experimenter's Corner

  - 

Improved Solar Powered Path Light

Good Idea done Badly

  - 

Bad LED Path Light II

New Products, 2010

  - 

New Products, 2010

What the World needs Now

  - 

Emergency Electrical Power System

Wily Widget, the Lone Inventor

  - 

Battery Charging Generator Starter

 

Issue 18 May 2011

Back of the Envelope Calculations

  - 

Solar Powered Laptop Computer

Circuit Diagnosis

  - 

CFL Lamps with Day Night Switch

Experimenter's Corner

  - 

Solar Alkaline Battery Charger

Good Idea done Badly

  - 

Bad Chinese Steel Products

What the World needs Now

  - 

Garage Door Closer

Wily Widget, the Lone Inventor

  - 

Hidden Panic Switch

 

Issue 19 Aug 2011

Back of the Envelope Calculations

  - 

Portable Solar Power System for Fence Installers

Circuit Diagnosis

  - 

Gapped Ferrite Pot Core Inductor

Experimenter's Corner

  - 

Human Walk Energy Harvesting Generator

Good Idea done Badly

  - 

Bad Floor Sweeper

What the World needs Now

  - 

AC to DC Power Supply with 40KV Isolation

Wily Widget, the Lone Inventor

  - 

Soap Dispenser Monitor

 

Issue 20 Nov 2011

Back of the Envelope Calculations

  - 

Long Range Laser Communications

Circuit Diagnosis

  - 

Super Hot Ferrite Transformer

Experimenter's Corner

  - 

Tiny Solar Panels Using Photodiodes

Good Idea done Badly

  - 

Bad Magic Mesh Screen

What the World needs Now

  - 

Broadband Antennas for Metal Shops

Wily Widget, the Lone Inventor

  - 

Touch Activated Battery Powered Latching Relay

 

1st Q 2012

Back of the Envelopes Calculations

  - 

Water Train

Circuit Diagnosis

  - 

Power Supply Problems - Excessive +5v Supply Current Drain

Experimenter's Corner

  - 

Testing LED Light Intensity

Good Idea done Badly

  - 

Bad Alkaline Battery Charger

What the World needs Now

  - 

Old style Wind Mill for Electricity Generation

Wily Widget, the Lone inventor

  - 

Shooting Range Flasher

 

2nd Q 2012

Circuit Diagnosis

  - 

15 Minute Timer Does Not Time Out

Experimenter's Corner

  - 

AC Current Test Source

Good Idea gone Badly

  - 

Bad Chinese Lag Screws

What the World needs Now

  - 

Big Dial Wind Speed Indicator

Wily Widget, the Lone Inventor

  - 

Illuminated Banister

 

3rd Q 2012 

Circuit Diagnosis

  - 

Swapped Parts

Experimenter's Corner

  - 

25 Watt-hour Battery Pack for Charging Devices through USB Port

Good Idea done Badly

  - 

Bad Bug Zapper

What the World needs Now

  - 

Water Heater Flame Detector

Wily Widget, the Lone Inventor

  - 

Single Lead-Acid Cell Voltage Monitor

 

4th Q 2012

Circuit Diagnosis

  - 

Inferior 50 Ohm Power Load Resistor

Experimenter's Corner

  - 

Home Made Current Transformers

Good Idea done Badly

  - 

Pirated Audio Books

What the World needs Now

  - 

An Anti-Theft Hanging Basket Alarm

 

How did you like DC Magazine?  Should we bring it back?
 Your comments are welcomed


 

 


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