October 2016

Arduino-based USB Electrocardiogram (ECG)

This exciting project lets you safely monitor your heart rhythm using the powerful Arduino platform and display the results on a battery-powered laptop PC. The software enables you to display and save the electrical waveforms generated by your heartbeat. The article describes an instrumentation amplifier ‘shield’ with software available separately from the link on this page (see right).

More interesting background information on the heart and its electrical activity is also included.

Various warnings and medical disclaimers are clearly shown throughout which must be heeded at all times.

For insulation reasons, this project must not be used with mains-powered laptops or PCs.

  Surface mount design needs good soldering skills

Compact hybrid switchmode 100W bench power supply (Part 2)

In the September 2016 issue we introduced our new 40V switchmode PSU which can deliver up to 5A, housed in a compact rack-style enclosure. This month the operation of the linear circuitry is described along with PCB considerations. Construction of the PCB and installation are explained. Final testing and setting up follows in Part 3 next month.

5-Element Yagi Antenna

In today’s world of digital downloads, trying to buy a high quality FM antenna is getting harder than ever. This home-made 5-element Yagi antenna (aerial) promises better FM reception, especially in remote areas where FM coverage is weaker. Far better than those cheap ribbon-cables often included with stereo systems, this ‘proper’ Yagi aerial is an updated version of a classic design that will transform FM reception. Full diagrams and parts list are included to enable you to build this design with confidence.

Introducing the Arduino
Part 9: LAN and Internet connection

This part of our extensive Arduino primer utilises an Arduino Ethernet shield to enable an Arduino to communicate over a network. The Ethernet library is explored in Coding Quickstart, and practical examples include using a router or hub to transmit data over Ethernet, and the construction of a highly accurate Internet-connected digital clock.  If you’re wanting to get into the fantastic Arduino platform, EPE’s Teach-In 2016 series is the place to start, so don’t miss out! Back issues are available from our Online Shop.

This month’s Teach-In full software listings can be downloaded from the link [see right]

Also in this issue:

• Circuit Surgery presents a primer on Phased-Locked Loops (PLLs), including some suggestions for popular PLL chips.
• TechnoTalk on trends in wireless data communications and cyber security implications
• Net Work offers a timely security reminder for Internet users of all levels
• PIC n’ MIX – Part 3 of a special series, PICs and the PICkit 3 : A beginner’s guide
• Audio Out – a special column for audio circuitry enthusiasts,  using ‘Smart board’ to build a low-power valve amplifier
• Practically Speaking – practical workshop hints and tips for hobby electronics fans
• Electronic Building Blocks – a ‘phone blaster’ audio amplifier from everyday modules

In next month’s issue:

Fingerprint access controller; Compact Hybrid SwitchMode 100W Bench Supply (Part 3), cheap PIC32 Programmer; Teach-In 2016 (Part 10): ultrasonic sensors and proximity detection.