Taking on the Big A/Big D Challenge - EDN-Design Ideas - May 03, 2001    The system-on-a-chip (SOC) revolution is well underway and with it comes a new set of technical challenges.  SOC design content leans increasingly toward "Big A/Big D"-large-scale integration of analog, RF, and mixed-signal content, along with a growing number of digital blocks.  For example, the LinEPIC*III mixed-signal process technology recently introduced by Texas Instrument Design  by Sanjiv Taneja

The Perpetual Swinging Pendulum - This project originally appeared in "Nuts and Volts" magazine August 2012 by David Williams.  It was titled "Build The Mystery Solar Powered Pendulum" and can be viewed at the link above.  It has been adapted here to operate from a couple AA cells.  The circuit board, magnetic coil, and battery are contained in a wooden cigar box, with balsa wood supports for the pendulum.   A neodymium magnet is placed at the base of the pendulum and held in place by the attraction of a small flathead screw at the bottom of the pendulum. __ Designed by Bill Bowden

TMS320C3X Wait-State Generator Uses Few Part - EDN-Design Ideas - 01/19/95    The TMS320C3X-family programmable wait-state generator inFig 1 snoops for memory-mapped devices requiring wait states, simultaneously enabling and loading its wait-state counter.  TMS320C3X data books and application notes describe the most commonly used wait-state generator for the TMS320C3X family of DSPs (digital-signal processors).  Although this factory circuit is ideal for explaining the principle of wait-state generation for the TMS320C3X family, Design  by Vladimir Bochev, Patrice Nus, François Devillard, Universitœ Henri Poincarœ de Nancy I, Vandoeuvre, France

Top 20 Mini Project Ideas For Engineers - Electronics projects are always in high demand. Students work on them to improve their skills, whereas hobbyists like the fun in meddling with technology. For professionals, it’s a different ball game __  8/31/2016 - EFY

Transistor Schmitt Trigger Oscillator - The Schmitt Trigger oscillator below employs 3 transistors, 6 resistors and a capacitor to generate a square waveform.  Pulse waveforms can be generated with an additional diode and resistor (R6).  Q1 and Q2 are connected with a common emitter resistor (R1) so that the conduction of one transistor causes the other to turn off.  Q3 is controlled.   __ Designed by Bill Bowden

Transistor, Diode, IC outlines - The LED flasher circuits below operate on a single 1.5 volt battery.  The circuit on the upper right uses the popular LM3909 LED flasher IC and requires only a timing capacitor and LED. __ Designed by Bill Bowden

Transition Maps Guide Successful Asynchronous State-Machine Design - EDN-Design Ideas - 05/12/94    To avoid the risks of asynchronous logic, designers too often sacrifice system performance by using synchronous designs.  Transition maps, however, help designers avoid the risks in asynchronous logic—and recover lost performance.  While ASIC houses and "good engineering practices" emphasize synchronous-design techniques, the increasing use of clock speeds as fast as 50 to 200 MHz is forcing designers to implement asynchronous logic circuits, instead.  Unfortunately, although most digital design engineers are familiar with combinatorial and synchronous sequential-logic circuits, the world of asynchronous sequential logic design remains obscure.  Transition maps can guide designers through this unfamiliar world to reach reliable asynchronous designs.    Design  by EDN Design Ideaby Ricardo O Rabinovich, Ascom Timeplex Inc

Triangle & Square Wave Generator - Here is a simple triangle/squarewave generator using a common 1458 dual op-amp that can be used from very low frequencies to about 10 Khz.  The time interval for one half cycle is about R*C and the outputs will supply about 10 milliamps of current.  Triangle amplitude can __ Designed by Bill Bowden

Ultrasonic Proximity Detector 2xBJT - Schematic only __ Designed by va3iul

Ultrasonic switch transmitter & receiver - The circuit described generates (transmits) ultrasonic sound of frequency between 40 and 50 kHz.  As with any other remote control system this cirucit comprises of a mini transmitter and a receiver circuit.  Transmitter generates ultrasonic sound and the receiver senses ultrasonic sound from the transmitter and switches on a relay __ Designed by Andy Wilson

Use an off-the-shelf signal source as a jitter/wander generator - 3-Feb-05 EDN-Design Ideas - Ensuring that new networked products, such as routers, gateways or DSLAMs (digital-subscriber-line- access multiplexers] meet stringent timing specifications usually requires a specialized jitter/wander generator.  As a substitute, you can use a standard function generator equipped with PM (phase modulation] or FM (frequency modulation] to measure jitter and wander tolerance Design  by Slobodan Milijevic, Zarlink Semiconductor

Valve Power Supply - The biggest problem with valves is the PSU needed to provide +250 vDC and 6.3 vAC for the fillaments.  The transformers are no-longer available at a reasonable price, but a pair of 12v-6v-0v-6v-12v mains transformers will do the job just as well.  For portable use only one transformer is required together with a pair of power transistors such as 2N3055 etc __ Designed by Harry Lythall-SM0VPO

Waveform conversion - sine to square and square to sine __  Contact: Charles Wenzel of Wenzel Associates, Inc.

Wide Bandwidth Cell Phone Jammer - Schematic only __ Designed by va3iul

Yaesu FT-857 Repair - I got a cheap, known-to-be-non-working, Yaesu FT857 that refused to turn on.  There was no sing of life when pushing the power-on button, nothing.  It did not take very long to find that the magic smoke inside two tiny parts was forced out to the outside world __ Designed by Roberto Barrios EB4EQA