Electronic & Embedded Projects
My electronics shop features a good bit of test equipment, some commercial (including an oscilloscope, a nixie frequency counter, a signal generator, and a Hakko soldering station) and some homebuilt including a 50 MS/s logic analyzer based on an AM7402 dual-port RAM chip which uses a PC (with a 17" LCD behind the bench) as a front-end display. The workbench, shown here with the colour organ project in progress, has a keyboard and mouse mounted on a pull-out tray beneath. Other test equipment visible here includes several power supplies, one a homebuilt unit with a variable 0-30V/3A output, and an old NTSC composite monitor on the upper-left shelf used for testing old vintage computers, primarily my Ohio Scientific collection.
As well as test equipment the shop has an entire wall full of parts boxes. Parts I stock include an assortment of discretes (resistors, capacitors, diodes), TTL (74xx) and CMOS (40xx) chips, and a host of microprocessor parts both current (PIC processors) and some deemed 'obsolete' used primarily to service machines I keep in my collection of vintage computers
I present, below, a collection of projects I have worked-on over the past few years. For over a decade, I had taught both embedded systems (microcontroller technology) and digital signal processing and practice what I preach: many projects here are microcontroller-based and employ PIC or dsPIC series chips from Microchip.
| DTV Antennas
Outlining my experiments with a multiple antenna system (employing both a Gray-Hoverman and a YAGI) for the reception of over-the-air signals.
| Digital Oscilloscope
A project for which I developed the firmware. Employing a dsPIC33FJ, this basic scope features a 1MS/s sample rate and a low-cost graphical LCD display.
An accelerometer employing a new MEMS 3-axis chip from Analog Devices. Uses a 3.3V dsPIC (33FJ series) and large SST flash memory chip. Data can be downloaded to a PC for analysis.
| DSP Colour Organ
1960's flashing lights meets 2000's DSP technology: a colour organ using entirely digital filtering and featuring constant volume adjustment and true phase-control of lights.
| MAME Arcade Machine
... capable of emulating almost any classic arcade game from the 1980's. Features details of the cabinet as well as a custom USB interface for the joystick and buttons using a PIC 18F4550 microcontroller.
| RV Fan Speed Controller
A low-tech speed controller for an RV air conditioner fan allowing the fan to run quieter and allow the unit to dehumidify better. In cludes an electronic anti-freeze up circuit.
| Pinball Machines
... chronicles the rebuilding of a 1980 pinball machine including repair of electronics (with replacement of obsolete components as well) and mechanical and artistic touch-ups.
| Win-32 Logic Analyzer
Presented is both the hardware and software for a Win-32 based Logic Analyzer. This is an updated version of an old project which now uses a USB interface, sports a 50MS/s sample rate, and supports 3.3V as well as 5V logic.
| Nixie Thermostat
A heating and cooling thermostat employing technologies spanning fourty years from the unique Nixie tube display, circa 1960's, to a PIC 18F microcontroller, circa 2006.
| Laser Light Show
A laser light show controller based on a 30F dsPIC chip. This vector-scanning system can produce complex images and allows upload of vector files via the serial port.
I was recently featured on Sixty Second Tech from Power Electronics News, an electrical engineering website dedicated to Power Electronics. The site features a host of links to other hobbyist sites as well.