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Battery-driven Bluetooth receiver for a wired headphone.

Ellie
Published on September 5, 2024

I swear, most people asked if that was a detonator…

So, my phone does not have a 3.5mm jack, and my headphones are not bluetooth…. I wanted to have a semi wireless solution so, I did the most MacGyver engineering thing ever. Behold!… the thing!

It’s ugly, but it works.

Basically, it’s a M28 bluetooth audio receiver for speakers that has a 3.5mm jack embedded on, with a 18650 charge circuit, a switch and a battery holder ( and the battery ).

The components

The concept is simple. Plug in the battery to the charge controller with a switch, and the output goes to the receiver. I swear, I was mostly just putting building blocks together here. I did a ‘dry assembly’ to see where things would fit before putting it together too.

Test fit

Once I was satisfied with the placement, I did a ‘tape assembly’ because I completely misplaced my glue sticks. >.> It also served as a prototype to bring at work to be able to use my headset in bluetooth.

Initial version, taped.

Everybody that seen it asked if it was a detonator. -_-

Ultimately, I ended up getting new glue sticks and did the final assembly like shown in the first picture.

Hope you enjoyed!

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