A Bluetooth pulse code modulation (PCM) lookback test primarily verifies the functionality of the Bluetooth chip’s PCM interface. The test involves looping back the SCO/eSCO data on the Bluetooth chip ...
Then, all you need to do is pop the adapter into the 8-track deck, pair with it over Bluetooth, and you can get the tunes pumping. Others have had success with hilarious Rube Goldberg methods, too.