How to create a Bluetooth Cassette Adapter 

  NOTE: It isn’t necessary to reproduce such Adapter. The Topic’s basic goal is to enrich your skills and creativity. As the main priority for us is understanding the principle of working of stuff. 

  During the searching process and Preparing the topic information, we have been found this impressive design, so we select exactly that video material. 

  First, the creator presents the ready device, after that he represents step by step all main activities, related to creating the explained BT Cassette Adapter device.

  See VIDEO 1. 

VIDEO 1. “How to make a Bluetooth Cassette Adapter”

   In the near past, there were very popular cassette tape players. Any important details over the main principle can be seen here:

   Basically, the audio over cassette tape is made by electromagnetic – electrodynamic recording head with driving reference speed of tape – standard 1⁷⁄₈ inches per second.

   The record can be represented as a linearly magnetizing over the length of the tape in 4 parallel tracks, whose can be separated as two Stereo pairs or two mono tracks.   

   Each pair is situated from equivalent – standardized distance from the imaginary center of the tape.

   So when you flip the cassette over the reading head is positioned another side – Stereo Tracks Pair.

   The Developer in Video is using Original Cassette For Standard enclosure for inserting the hardware.

Hardware includes:

• Standard Cassette enclosure for integrating the Project,
• Playback-Head from Standard Old Portable Walkman,
• Micro Switch with Arm,
• Specialized Bluetooth BT PCB*,
• Specialized MicroUSB-B, Single Li-Ion Charger PCB**,
• Small Rechargeable Lithium-Ionic Battery (e.g. GSP 150 mAH, 3.7V ) or similar.

* BT PCB for interconnection between, e.g. Smartphone and Hi-Fi Cassette Playback System – at 3:22 min from the beginning of the Video,

** Micro USB – Type B, One Cell Li-Ion Battery Charging PCB  – TP4056,

PCB * 7 pins: 

• Vcc+5v,
• GND,
• Left Audio Channel,
• Right Audio Channel,
• Mute Audio,
• LED Pin 1,
• LED Pin 2, 

Bluetooth Board 7-pin Aliexpress Affiliate Link:

Note: If you decided to order – Select 3.7V option

PCB ** (TP4056)

SDTC Tech 2pcs. Micro USB-B 5V / 1A Battery Charging Protection Board TP4056, for single cell 3.7V Lithium Battery:

• Input voltage: 5V
• Charge cut-off voltage: 4.2V + / – 1%
• Maximum charging current, using micro USB-B: 1A
• Battery over-current protection current: 3A
• Battery DeepDischarge protection voltage: 2.5V
• Charging status indicator: the red light for charging state and the green light for fully charged.
• Connecting:
  • B+ connect to battery positive terminal,
  • B- connect to battery negative terminal,
  • OUT+ connect to load positive terminal,
  • OUT- connect to load negative terminal.

Diymore 10pcs. Micro USB-B 5V / 1A  Battery Charging Protection Board TP4056, for single cell 3.7V Lithium Battery:

Diymore – Key Features:

• Input voltage: 5V
• Charge cut-off voltage: 4.2V + / – 1%
• Maximum charging current, using Micro USB-B: 1A
• Battery over-current protection current: 3A
• Battery deep-discharge protection voltage: 2.5V

Additional Accessories:

• Gray Painting Spray suitable for plastics,
• Sticky Tape for painting protection,
• Cutting tool, Modeling Knife,
• Dremmel, 
• Cyanoacrylate or equivalent Moment Action Glue,
• Some Plastics and Fabric Glass Pieces,
• Sandpaper,
• Your skills, inexhaustible creativity, and energy.

Conclusion:

  Independently, the video duration isn’t too long, this Video Design, as I could name it,  can improve your DIY skills and Your Creativity in a few aspects:

• Mechanical – Cassette Player Playback Head un-mount and Customize – Preparing, 
• Mechanical – Preparing, Gluing, Painting, 
• Theory – Inductance, Electromagnetism,
• Electronics: Li-Ion Charger Basics. Additional materials and more theory can be found here.
• Electronics: BT Board Basics. Additional materials and more theory can be found here.
• Electronics: Soldering. Additional materials can be found here.