- FAQ

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I have anticipated some questions that users may have concerning my ECG (EKG) projects. Feel free to send me any other questions – use the about page to find my details.

What is an ECG?
Please see my page on what ECGs actually are.

Where do I place the ECG sensors to get a good reading?
Please see this site and this site for instructions on where to place the electrodes for an ECG.

Why is an ECG useful?
An ECG allows a health worker to screen for heart conditions, be they genetic, chronic or acute. Simple factors like an elevated ST interval can indicate the presence of a myocardial infarction. Cardiologists may choose to record an ECG of a patient to determine other factors, including damage to the heart, function of conducting areas and areas of issue.

What besides screening can an ECG be used for?
The technology present in any ECG can also be used to measure the electrical conductivity of other tissues, for example muscle contractility – tested in an EMG (Electromyography).

How do I build an ECG?
Please see Jason’s page, linked both here and also on the home page for simple instructions to build an ECG. Another option might be to purchase a second hand unit from an auction site like ebay or oztion. Building an ECG requires some basic electronics skills, including soldering, component identification and understanding a circuit diagram. All this information (and more) is freely available on the internet.

Is it easy to build/operate an ECG?
‘No’ to both. It is a difficult project because of the small tolerances involved both in circuit design and construction. The electrical impulses generated by action potentials in heart muscle and nerve axons are tiny – measured in millivolts (mV), and can be easily overwhelmed by other sources of electromagnetic interference. For example, mobile phones, computers and any mains connected appliance can cause issues when operating an ECG – due to simple interference. In my projects I have struggled to avoid 50Hz hum from electronics (the power in Australia is 240V AC, 50Hz). Operating an ECG is tricky – but many practice sites can be found on the internet, including java applets, flash modules and other resources (The site listed works better in IE than Firefox. It’s definitely worthwhile if you have the time, and can make future health related work easier.

Can I use my ECG medically?
No! Please do not attempt this. Isolation is an issue in both projects listed here, and none of the technology has undergone rigorous testing to ensure safety. Use strictly at your own risk – I do not advocate using this technology unless you understand it and the risks associated.

Where can I find out more about ECGs?
Please see this page for more information on how ECGs work & how to read and understand them.

More information
Please see the site map of this site about ECGs