March 2018 Issue

A summary of this month's contents.

Stationmaster PWM Model Railway Track Controller

This pulse-width modulation (PWM) controller is just the thing for smaller model railway layouts, offering train enthusiasts all the features needed for realistic and stable speed control. It includes a hand-held controller for ‘walk around’ use that can be connected to sockets conveniently located around your layout.


Features include forward & reverse, speed, inertia (momentum) and emergency brake. It has a fully-protected H-bridge motor controller output stage offering up to 3.5A with adjustable current limiter. Discrete circuit design with a very small amount of surface-mount soldering needed.


SC200 Amplifier Module

(Part 3)

In this third and final instalment we provide the SC200’s performance details, power supply details plus a suggested initial safe power-up procedure.


Using Cheap Asian electronic Modules (Parts 2 & 3)


We’ve a double bill for readers this month! Firstly we examine the ready-made HR-SR04 ultrasonic distance module, showing how it works and how to use it in various monitoring applications with a Raspberry Pi, Arduino or Micromite.  Secondly this month, a computer interface module based on a serial USB-UART is explored. It allows just about any microcomputer or peripheral module to exchange data with a PC, via a standard USB port. Plenty of practical hints and tips in this article!


Teach-In 2018 – Get Testing! Electronic test equipment and measurement techniques.

Part 6: Audio frequency measurement and testing


This in-depth hands-on primer continues with tutorials on the specifications for audio frequency equipment including pre-amps, filters, tone controls and power amplifiers. Many common parameters such as distortion,  hum, crosstalk, frequency response and more are explained along with an overview of test equipment useful for AF-related tasks.

Audio Out

Our column for serious sleeves-up audio circuitry enthusiasts. A single-rail modification for the MX50 amplifier module is described this month.


Electronic Building Blocks

A cheap and cheerful multi-mode flasher module from China is explored.  Available from eBay, it’s useful for high-power LEDs or incandescent loads. Usage considerations are included in this month’s feature.


Also in this issue


  • Techno Talk – the impending threat of solar flares
  • PIC n MIX – utilising four-digit 7-seg displays (Part 4)
  • Net Work – why some websites contain hamburgers!
  • Circuit Surgery – system power supply switching and load switch ICs are explained


Next month

Spring Reverberation Unit;  Touchscreen DDS Signal Generator; Upgrade your Arduino Theremin; Teach-In Part 7 – Radio Frequency measurements; Low-Cost Electronics Modules (Part 4): digital temperature and RH sensing module. Contents may be subect to change.


EPE is packed with practical electronics projects and theory for the hobbyist. You can order a printed copy of EPE for delivery to your door (worldwide), or try the PDF Version (needs Adobe Reader for Windows), or the Pocketmags for your mobile device. Subscribe now!



Source code file [PIC n MIX, Stationmaster artwork] -


Download Help


Can't find what you're looking for? Our Library Help Page offers extensive information and help with downloading files.


The March 2008 issue had a Multi Throttle Controller for PC flight simulators, a 6V Fluorescent Tube Driver, the Studio Series Stereo Headphone Amplifier and Midi Drum Kit (Part 4)


PCB artwork


As from July 2013 issue PCB artwork is available free to subscribers only.


Non-subscribers may purchase artwork files for a nominal sum. Please contact our Orders Dept for information or to place an order.


EPE Printed Circuit Boards


We can supply ready-made printed circuit boards (8-digit order codes) to the original design specification via mail order or from our Online Shop.

Custom Search