Want a better experience watching media on your smartphone? This DIY build should be right up your street! In this one we'll be building on the previous portable monitor project and designing a battery system and speakers for it to transform it into a high quality wifi TV! Previous video that this one is based off: Purchasing links below. Third Hand: Chromecast (official): Speakers: Amplifiers: Voltage meter: Voltage regulators: Battery box: Charger: BATTERY METER CALIBRATION: The bottom variable resistor sets the high voltage point (or 'full charge' voltage), so set this first when batteries fully charged; clockwise lower voltage, anticlockwise higher voltage. The top variable resistor (near the button) sets how broad the range is, so set this afterwards to get the low voltage point at low low battery power, anticlockwise lower, clockwise higher. Low voltage should be about 10v when the batteries have no load connected. The clips playing on the screen were from the trailers for Planet Earth 2 and Assassin's Creed.