bone conduction pen - ebay find - teardown

Another strange eBay find, a Tiger Electronics Sound Bites FM radio pen from around 2000.

It is a normal writing pen with an FM radio built into it. You can listen through the small speaker attachment, or bite the end of the pen and hear the sound through vibration. The instructions even suggested putting a lollipop in the end and biting the stick.

The radio is tuned with scan and reset buttons and runs from two AAA batteries.

It was a cool gadget for its age, but the radio reception was not very good and the sound was not loud enough for my taste.

If I were building it with newer parts, I would use a small rechargeable LiPo battery, Bluetooth for phone audio, a microphone and push button for walkie talkie use, and make the whole thing much smaller.

There are several options for producing the vibration, including a piezo element, vibration motor or a proper bone conduction transducer. It might even be interesting to try more than one transducer and see whether some kind of directional or stereo effect is possible.

Teardown photos below.

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