A small collection of electronic circuits for the hobbyist or student. Site includes 100+ circuit diagrams with text descriptions, several electronic calculators, links to related sites, commercial kits and projects, newsgroups, and educational areas.
Most of the circuits can be built using common components available from Radio Shack, Digikey, Jameco, Mouser, Allied electronics, or salvaged from scrap electronic equipment. Most circuits have been built, tested, and believed to perform as described, however possible mistakes may be found.
What's New Here? (09/15/16)
Semiconductor Data Sheets
TI Semiconductors (search) National Semiconductors (search) Motorola NTE Datasheet Archive
Java Script CalculatorsResistor Color Code Calculator - Graphical resistor color code calculator by Danny Goodman. Uses pulldown menus and a realistic picture of a resistor.
4,5,and 6 Band Resistor Color Code Calculator - Graphical 4,5 and 6 band resistor color code calculator including tollerance and tempco.
Another Resistor Color Code Calculator - This one uses check boxes instead of pulldown menus and also calculates the equivalent value of two resistors in parallel. My own creation.
Ohm's Law Calculator - Java Script to solve Ohm's Law for Voltage, Current, Resistance and Power. Enter any two unknowns and solve for the other two.
Voltage Divider Calculator - Solves voltage, current, and power dissipation problems for two element resistive voltage dividers.
L or C Reactance Calculator - Java Script to calculate capacitive or inductive reactance and resonant frequency. For ideal devices only, resistance not included.
RC Time Calculator - Java Script to solve R and C values for given values of time or instantaneous voltages.
RL Time Calculator - Java Script to solve R and L values for given values of time or instantaneous current.
555 Timer - Frequency and Time Interval Calculator - Calculates positive and negative time intervals for the 555 timer based on R and C values. Also contains descriptions and operation of each input and output of the timer and schematics for the two basic modes of operation (monostable or "one-shot" and astable or "rectangular wave oscillator"). Also contains a pictorial diagram of the timer connected as a LED flasher and a table of connections for the 556 timer (dual 555 timer).
LED Series Resistor Calculator - Finds the series resistance needed for various series LED combinations and supply voltages.
Air Core Inductance Calculator - Calculates number of turns and layers needed for air core inductors.
Gregorian Calendar - Displays any month from Oct 1582 forward.
Links to Other Hobby Electronics Sites and Useful Information
Don Klipstein's LED Website - Lots of useful LED information, FAQs, and sources for the brightest and most efficient LEDs.
Circuit Archive - University of Washington Circuit Archive, lots of good circuits and links.
Tomi Engdahl's Electronic Info - Links to a wide variety of analog and digital circuits.
Imagineering Imagineering On-Line Magazine,The Design Corner, over 100 circuits in pdf format.
Links for FM Transmitter Kits, Circuits, Electronics ...
Tony's Website - Free electronic circuits, R/C Gadgets, and tutorials for the hobbyist. Site in operation since 1995.
Steve Walz's FTP Site - FTP Resource Site, 1000 Files in 50 Directories.
Wenzel and Associates (Circuits) - Technical Library, Hobby Circuits.
Samuel M. Goldwasser Homepage - Silicon Sam's Technology Resource - FAQs, Links, Troubshooting & Repair, Laser info, Circuits.
Deep Cycle Battery Frequently Asked Questions
Wonton Soup Recipe This recipe was copied from a local Chineese take out place. Costs $5 to buy it, and only $2 to make it.
Commercial Electronic Sites, Kits and Projects
Electronics Educational Sites
Electronic Component Suppliers
For help with circuits not listed here, please post a message with details to one of the electronic newsgroups, either sci.electronics.basics or sci.electronics.design Many readers of those groups will offer ideas and a few specifics at no charge.
For help with specific circuits on this site, or some minor modification, please email the details and I will try to resolve it. I can also build completed circuits shown here for a small fee depending on time involved.
Please do not attach large files over 200K to email messages. I still use a dial-up connection with minimal bandwidth, and cannot download large files over 200KB.