Electronics

2006

Induction cooker Brief investigation of the waveforms in a 2kW induction cooker.

2008

PCB drilling viewer Gadget to drill PCB boards by optically aligning the underside of the board with the drill axis

Surface mount component soldering arm Useful tool for holding surface mount components in place whilst soldering

PowerPAD™/MSOP-8 heatsink Small copper-foil heatsink for PowerPAD™ IC packages to allow hand soldering

2009

Dual AA battery eliminator If, like me, you have a little digital camera which runs from two AA batteries, then you probably will be fed up with using a lot of batteries when you're taking pictures or videos around the house. This little circuit is a simple 3V adjustable regulator which runs from a 5V supply. I made the adaptor to fit a Nikon L2 camera, but it should work with anything.

2010

Laser-cut solder stencil Trial of making a solder paste stencil using transparency film cut with a CO2 laser.

LED on conductive glass A surface-mount LED mounted on a piece of conductive glass.

Nixie tube counter Simple counter circuit to drive a Russian IN-8 nixie counter tube using a PIC. Also interfaces to a telephone rotary dial.

Digital Kirlian photography Using a digital camera to take Kirlian photographs.

Excellon to G-code converter Program to convert Excellon drill files from Eagle to G-code suitable for running a CNC machine. Also performs geometric transformations to correct for distortion in the board.

Large IC model A 10x scale wooden model of a 555 timer IC

2011

Double-sided exposure alignment jig A useful jig for exposing double-sided things, such as for PCBs or photochemical etching.

New 3V camera supply A better 3V supply for my digital camera, this time built in an ATX supply case.

Planté rheostatic machine A completely mechanical means of charging a string of capacitors in parallel and discharging them in series to obtain increased voltages

TIG welder with HF start This is not my work, but is a backup of a page I found on another site. It describes the construction of a 180A TIG welder with high-frequency start.

High-voltage trigger and capacitor dumper This arrangement was originally designed as an attempt at pulse arc welding, but is useful where a high-voltage, high-frequency trigger pulse is required.

Power ultrasonic driver Inverter power supply for a 28kHz ultrasonic tank transducer

Spark radiation detector Spark detector for α particles

Surface mount adapter boards Allows SMD devices to be used on a 0.1"-pitch breadboard

40-400V, 20W power supply General-purpose high-voltage power supply for experimenting with Nixie tubes and the like

Making a current-sense resistor How to make a low-ohmic sense resistor using a short piece of resistance wire

Potentiometer end-stop modification Altering a cheap carbon potentiometer to obtain smooth adjustment at the end of the wiper travel

ICSP adapter for EasyPIC5 Making an adapter cable to allow PICs to be programmed externally

TV CRT Tube Socket Socket for TV CRT necks

Large resistor model Painted wooden model of a ¼W resistor

Bayonet bulb plug adapter Plug to make electrical connection to a light socket

Faulty PCB pin header connectors Not all 0.1" PCB pin header connectors are created equal. A particular intermittent fault was traced to bad connectors.

2012

Triggered spark gap A triggered spark gap using stock hardware

Removing ground/earth from site transformer This mod allows a site transformer to be used as an isolation transformer with a 110V output.

1000x capacitive high voltage probe A high voltage oscilloscope probe suitable for measuring fast HV pulses

Resistor colour code chart High-resolution chart of resistor colour codes

Using an external coil with an induction cooker Winding a coil to fool an induction cooker into thinking it's running its original coil

Modifying a rotary switch Converting a 4-pole 3-way switch into a 1-pole 12-way version

Wide-range adjustable pulse generator A circuit to produce pulses anywhere from 200ns to 500ms

Inductor tester Simple circuit for measuring the saturation current of inductors

Hot air gun circuit and operation The insides of a cheap Clarke hot air gun

High-voltage diode stack A potted stack of UF4007 diodes to make a 48kV dual diode

Inductor properties A quick look at how inductor properties (inductance and saturation current) vary with turns and air gap

Series HV trigger Simple circuit for series triggering of spark gaps, arc lamps etc.

Large Brandenburg flyback transformer A huge flyback, unfortunately with a cracked winding

Small variac transformers Two small variacs I picked up a while ago - one has an isolated low-voltage secondary, which is a bit unusual.

PCB via size test Checking to see how small a via I can make with home etching

Improving ADC resolution by adding noise Deliberately adding noise to an analog signal can improve the resolution achievable

Fixing a transformer thermal cutout Repairing the transformer in a small desk lamp

Load resistance on PIC's programming pin If a load resistance is present between the MCLR/VPP pin and ground, programming may not work correctly

2013

High-speed photodiode Detector using a BPX65 photodiode

High-value resistor mixture Using a mixture of Aquadag and PVA glue to make high-value resistors

Flyback HV supply Some photos of my old high voltage supply

Read-modify-write problem Be careful when using tri-state PIC outputs!

Making PCBs My own experiences with making PCBs