About delabs

delabs is a web-service for product design and development.

G-switch timer – Vern Knowles

The timer is built using four small inexpensive CMOS integrated circuits. This allows it to run on just 3V from two small AAA batteries. U1 is a 74HC688 8-bit equality comparator. It compares the switch settings to the counter output and will set pin U1-19 low when they match. The actual counter is U2. It is a 74HC4060 14-stage binary ripple counter with built-in oscillator.

The G-switch itself uses a cantilevered metal bar that pivots down as the rocket accelerates upward. The metal bar actuates a small micro-switch that triggers a digital counter to begin the timing sequence. The timer is designed so that it will not start unless the micro-switch has been activated for a duration of at least 0.5 seconds.

G-switch timer - Vern Knowles

G-switch timer – Vern Knowles – The timer was built using a small prototyping circuit board and point-to-point wiring.

U3 is a 74HC74 D-type flip-flop that is used as part of the triggering logic. U3-12 will be low when the counter matches the switch settings. Consequently, on the next oscillator clock edge from U2-9 the flip-flop output at U3-9 will go low. This is the event that activates the 2N4403 transistor that fires the flash bulb.

Thaikits – Electronic Kits for Learning

A group of test engineers in Thailand who worked in an Electronic factory more than 12 years have started a small business to sell electronic projects and electronic kits worldwide in 2007.

CH012 Transistor Curve Tracer adapter XY Oscilloscopes 2 ranges Bias

Thaikits - Electronic Kits for Learning

Some interesting kits are HHO High Frequency PWM DC Motor Speed Controller 30A, CH018 Cycling Timer 1.5 -180 minutes ON-OFF 12VDC/30A Heavy Duty 110V/240VAC, CH024 ICL8038 Function Generator Sine Triagle Square wave 0.5Hz-100kHz.

5/16 Moo 18 ,Bueng Kham Phroi,Lam Luk Ka, Pathum Thani 12150, Thailand

The Art of Electronics – Paul Horowitz Winfield Hill

The Art of Electronics covers the full range of subjects normally treated in electronics books, as well as a rich complement of important but neglected topics.

The Art of Electronics, by Paul Horowitz and Winfield Hill

The book covers many areas of circuit design, from basic DC voltage, current, and resistance, to active filters and oscillators, to digital electronics, including microprocessors and digital bus interfacing. It also includes discussions of such often-neglected areas as high-frequency, high-speed design techniques and low-power applications.

The Art of Electronics - Paul Horowitz Winfield Hill

Learning the Art of Electronics – A Hands-On Lab Course

This introduction to circuit design is unusual in several respects. First, it offers not just explanations, but a full course. Each of the twenty-five sessions begins with a discussion of a particular sort of circuit followed by the chance to try it out and see how it actually behaves.

The Art of Electronics – Paul Horowitz Winfield Hill

The book includes many example circuits. In addition to having examples of good circuits, it also has examples of bad ideas, with discussions of what makes the good designs good and the bad ones bad. It can be described as a cross between a textbook and reference manual, though without the chapter-end questions and exercises which are often found in textbooks.

Paul Horowitz is a Research Professor of Physics and of Electrical Engineering at Harvard University, where in 1974 he originated the Laboratory Electronics course from which emerged The Art of Electronics.

Winfield Hill is by inclination an electronics circuit-design guru. After dropping out of the Chemical Physics graduate program at Harvard University.

Elektronik und Mikrocontroller – Burkhard Kainka

Author of books and CDs, Microcontroller, interface programming or new ideas for hobby projects. The Electronics Fundamentals for hobby and education helps the beginner with valuable information.

The electronic logbook is amazing, you can have a look at so many circuits and projects with photos. You will learn many things and make you develop skills.

Elektronik und Mikrocontroller – Burkhard Kainka

For the advanced Hobbyist there are projects on Microcontroller and Measuring and control devices with the USB and PC Interfacing,

Burkhard Kainka - SDR Radio

SDR Radio with USB

Electronics experiments for children – “For children it is easier than for adults. Since it is enough, if someone applied sufficient time and a little tinkering with them. Often all it takes is a little push to arouse interest and skills.”

Electronics 2000 – Beginners Guide

Hobby Electronics – Software, Calculators, Forum, Technical Data, Pin-outs, Beginners Guide, Links.

Electronics 2000 – Calculators

A beginners guide to project building, technical data, interactive formulae calculators, software downloads including Electronics Assistant and EPE Index.

Electronics Assistant

Electronics Assistant is a Windows program that performs electronics-related calculations. It includes a resistor colour code calculator, resistance, capacitance and power calculations and more.

  • New 555 timer, voltage regulator & RC filter calculators
  • Enhanced series / parallel resistance & capacitance calculator
  • Calculation of preferred capacitor values with a choice of series from E6 to E24

Flashing Mains Neon Lamp

Here is a Neon Flasher circuit (untested) for a user request at Circuits FAQ. This can be built into a switchboard or a gadget for indicating Live Power.

D1-C1 form a simple half-wave rectifier, The Cap charges to peak voltage and can store charge for a long time if there is no bleeder. So while building it take extra care. This forms a DC supply across C1. C1 is a Plastic High-voltage cap, IN4007 has a 1KV rating, so it is ok for 230V rectifier.

R1 Charges C2 and when C2 reaches 60-80V depending on Neon, the neon breaksdown. C2 Discharges, Neon Recovers, The C2 starts charging again and so on and on. It Oscillates, probably in a Ramp Waveform. But do not use your Scope on this, you will regret it a lot. This is a live circuit and needs a special probe.

“Oh, i will put the probe it in 10M mode” will not do. The ground clip of the probe goes to Electrical Earth which is ‘connected’ to Neutral in the mains wiring. So you put the earth crocodile clip on the live point. There will be flashes and fireworks. So you need to isolate both terminals of scope. Please use your costly equipment with great care.

For the 1 Meg use two 470K in Series for 230V AC, that is safer. The circuit is live, so take precautions. The 0.47 Micro Farad can be increased if you want a slow flash. If the Mains 50/60 Hz Flicker is too much, the 1 uF can be made 2 uF, or use 4 – 1N4007 as a bridge rectifier.

From Schematics of delabs

User Feedback –

R1 of 4.7M and C2 of 0.47uF Works well at 230V AC. Try your own Combination. Less than 1M may damage Neon.

Adafruit Industries – Unique DIY electronics

Adafruit Industries is a small company that sells kits and parts for original, open source hardware electronics projects featured on ladyada as well as other cool open source tronix that I think are interesting and well-made.

Adafruit Industries – Unique DIY electronics

All the projects are redesigned specifically to make it easy for beginners to make: nicely silkscreened circuit boards, through-hole parts whenever possible, extra large solder pads, etc. For some kits, you can purchase just the circuit board. To save paper, the easy-to-follow-with-lotsa-pictures instructions are all available online, at ladyada.net-make.”

Boarduino Kit Adafruit

Atmega328 chip has twice as much storage, runs at 16.00 MHz, just like the latest Arduino. Upload baud rate is 57600, use Arduino IDE v13+. Chip comes preprogrammed with my “no-wait” Arduino bootloader.

  • Designed to plug into a breadboard for easy prototyping
  • Petite size, only 3″ x 0.8″ (75mm x 20mm)
  • All ‘standard’ pins are brought out – Digital 0 thru 13, Analog 0 thru 5, ARef, 5V, Ground, Vin and Reset
  • Chip comes preprogrammed with a “no-wait” Arduino bootloader
  • 2 LEDs, green power and red “pin 13” just like the Arduino Diecimila
  • Available as a low cost kit with standard parts, so its never out of stock
  • All through-hole parts are easy to solder

Boarduino (Arduino Clone) Kit

This clone acts just like an Arduino, and works with the latest Arduino software. For many projects it can even be preferable! The kit includes all parts necessary, the assembly is straightforward and well documented.