Projects in the February 2007 issue of EPE Magazine

The No. 1 UK Magazine for electronics technology and computer projects

12V Deep Cycle Battery Charger (Part 2) — full constructional details are supplied in the second part of our project. Our Deep Cycle Battery Charger is a sophisticated unit that is specially designed for deep cycle batteries and will charge at up to 16.6 Amps.

PIC Digital Geiger Counter — using the power of a PIC 18F2455 at its heart, our new Geiger counter detects ionizing radiation and can capture data for later downloading onto a PC. This portable device has an integral high voltage supply to drive a compact Geiger Mueller tube. Data is displayed on a 4-line LCD display. Built-in USB interface for computer uploading, and the free PC software is written in the latest version of Visual Basic.Net.
PLEASE TAKE NOTE: A REVISED DIAGRAM HAS BEEN ISSUED FOR THE MAIN P.C.B. THE NEW OVERLAY DIAGRAM INCLUDES SOME DETAILS OMITTED FROM THE PUBLISHED ARTICLE. It is sent with all PCB orders, and is available in the PCB Downloads section along with the PCB masters, as usual. (See March 2007 edition for a corrected image.) Unfortunately the Parts Listing for the Capacitors and Resistors is incorrect. Except for VR1 (which should be 100k) the values in the circuit diagram are correct.

Programmable Robot Buggy — this programmable buggy is fully manoeuvrable and has Pulse Width Modulation speed control and H-bridge MOSFET gearmotor drivers. It also sports bump and respond, random motion, Programmable sound, light sensing and EEPROM byte-wise programming. Based on a PICAXE-08 micro for simplicity, this is an ideal introduction to creating PC-programmable applications using microcontrollers. Our article includes all necessary diagrams and photographs to enable beginners to assemble the design successfully.

Courtesy Light Delay — give your car that luxury feel with our courtesy light (dome light) delay unit. Uses a MOSFET and opto isolator to safely and effectively fade the light once the door has been closed. Adjustable period from 7 to 40 seconds. No standby current means no battery drain, and it works on any 12V system. Can also be modified for 24V truck systems.

Also in this issue: "C" for PICs" - USB control of LEDs. Net Work (the Internet page) with more hints and tips for MS IE7 users and shopping online effectively. Interface describes improved Visual Basic controls. Circuit Surgery - our electronics expert tells you all about line levels. Everything you need to enjoy your hobby, in the No. 1 electronics magazine! Subscribe now!