13th December 2014
A simple field mill made from PCB material and a small electric motor.
Parent article: Advent Calendar of Circuits 2014.
1st December 2014
Another year, another circuit project per day for 24 days!
Contains 3 sub-articles.
1st December 2011
A circuit project per day for 24 days.
10th July 2011
BPW34 photodiode based gamma radiation detector.
26th December 2010
Experiments in wireless power transfer for a practical application, lead to some interesting side-bar observations on plasma physics, and the cutest little Tesla coil you've ever seen.
Contains 1 sub-article.
5th June 2010
I get oddly low results when attempting to measure the speed of sound in Water and Aluminium.
4th January 2010
Arcing fault destroys the Rope Light controller.
Parent article: Rope Light Christmas Star.
28th December 2009
A web-based emulator for the 240 LED Christmas Tree project.
Parent article: 240 LED Animated Christmas Tree.
28th April 2009
I lash up an old Geiger tube and monitor the background radiation in the shack for a while.
23rd March 2009
The beginnings of a photoplethysmographic cardiotachometer.
1st March 2009
A multiplexed 7-segment digital display for the bolometer.
Parent article: RF and Optical Bolometer.
2nd January 2009
Using BJTs and LEDs to implement ring counters.
28th December 2008
I try my hand at designing a switchmode power converter for a B+ supply using an Atmel ATtiny13 for the controller.
23rd November 2008
A simple 100 kHz to 30 MHz sweep generator.
18th October 2008
New "clean" URLs for the website and a new calculator engine.
3rd May 2008
A hack to unbrick ATtiny13s that you've stuffed up the fuses of.
27th April 2008
More progress on the PSK-31 beacon.
Parent article: PSK-31 Beacon Mark 1.
20th April 2008
Prototype PSK-31 Beacon Keyer.
Contains 1 sub-article.
29th March 2008
A prototype tone-coded multi-channel remote control system.
23rd March 2008
Various toy AM transceiver circuits on 11 metres.
Contains 1 sub-article.
1st March 2008
Building a toy VHF phone transceiver for 3 metres using only one transistor for both TX and RX!
4th January 2008
Experiments with an RF degenerate parametric oscillator using several different non-linear devices.
30th December 2007
A fairly trivial Cellular Automata implementation as a Java Applet.
24th December 2007
Thoughts about building cellular automata in hardware.
16th December 2007
Some experiments with a tuned receiving loop for HF.
14th July 2007
Experiments with Charles Wenzel's "Passive Aircraft Receiver" circuit.
Contains 1 sub-article.
15th April 2007
An 80 metre super-heterodyne SSB receiver built using BC556 devices only.
14th January 2007
My experiments with the VK2ZOI Flower-Pot antenna for 2 metres.
13th January 2007
My work towards the ARNSW Homebrew Group's "2007 80m Homebrew Challenge" transmitter project.
Contains 11 sub-articles.
18th November 2006
My go at making a JF1OZL-style spectrum analyser for 40 metres.
11th November 2006
A simple filter-based SSB exciter. Still work in progress, but will some day become an SSB transceiver.
4th April 2003
Going LF/VLF/ULF with a large multi-turn loop.
11th November 2001
A small experimental HF rig based on a Permeability Tuned Oscillator for the VFO. Currently on 20m, but the plan is to move it to 80m once debugged.