Bluetooth adapter from wireless earphones
The adapter can easily be made from headphones. We pull out the stuffing, instead of the battery bring power from the power supply for 3.7-4.2 volts, solder a wire with two tulips (RCA) on the contacts of the speakers, and it's ready.
Design engineering communications:
Electrical;
Water supply;
Heating;
Ventilation;
Hardware and microcontroller automation.
Design, maintenance and automation of mining locations of any complexity. Using the heat of asics for domestic needs:
Air and liquid heating systems;
Pool heating;
Supply air heating of ventilation systems;
Heating of greenhouses and any other technical premises;
Hot water supply;
Excess heat discharge to the outside/ventilation system exhaust;
Various farm cooling systems;