Summary
The Engineering Octopus created the Oscilloscope Tester Keyring (OTK), a portable keyring device that generates a pure sine wave for testing oscilloscopes. It uses a Colpitts resonant oscillator to produce frequencies around 10MHz, 20MHz, or 50MHz with a DC offset to test various scope functions. Powered by a 2032 watch battery or USB, the OTK is compact and convenient for engineers who need to test or repair oscilloscopes, especially when probes are unavailable.Parts used in the Oscilloscope Tester Keyring (OTK):
- Colpitts resonant oscillator
- Battery holder for 2032 watch battery (battery not included)
- Micro USB port
- BNC connector
- Electronic components for sine wave generation circuitry
The Engineering Octopus has launched a keyring which helps you keep track of your keys, and also serves as a means to quickly test an oscilloscope. It is called the Oscilloscope Tester Keyring (OTK). About the inspiration for the project, Max the brain behind the OTK says
All electronic engineers love to show off the fact that they’re electronic engineers, and what better way to do that than with a keyring! Not only will the bare electronics be noticed by many, it’s also a functional tester!” He continues “I made it because I wanted a tool I could take with me, to easily test oscilloscopes when I go and view them. Often, they don’t have the probes or any means of testing. Plus, I really wanted a cool electronic key ring, and I couldn’t find one!
The OTK works by generating a pure sine wave (via a Colpitts resonant oscillator) at a particular frequency (current models generate either approx. 10MHz, 20MHz, 50MHz) which is ideally close to the bandwidth of the scope. It features a DC offset, which enables you to test almost all functions of the ‘scope, and carry it with you everywhere you go! It’s battery powered (not included) via a 2032 / watch battery. It also features a micro USB port so that you can use the oscilloscopes (or power banks) USB port for power.
About the scope, he says “
But my ‘scope has a square wave function, I hear you cry? Indeed, this is true, but firstly it doesn’t fit on a key ring / look cool, and secondly, you need probes to test it! Where the OTK really shines, is for those of you who love to repair / buy ‘scopes. More often than not, they’re not supplied with probes, and this is a quick and easy tool that can be taken with you to viewings. You simply plug it into the BNC connector, and test it out!”
Read more: OSCILLOSCOPE TESTER KEYRING (OTK) CAN TEST YOUR OSCILLOSCOPE
