Bone conduction is a method of sound transmission. The sound is converted into different frequencies of mechanical vibration and transmitted through the human skull, bone labyrinth, inner ear lymphatic transmission, helix, auditory nerve and auditory center. This kit is composed of a bone conduction speaker, a speaker driver board and accessories. The kit is intended to help understand the principles of bone conduction technology, making hearing aids or bone conduction headphones. The speaker driver board is designed based on MAX9814 microphone amplifier and PAM8406 amplifier, high sensitivity and suitable for 3.6v-4.2v lithium battery power supply. It comes with a potentiometer that has a power switch function making it easy to control. Components Description Power Input 3.0~5.5V AGC Switch Plugged: AGC OFF Unplugged: AGC ON Audio Input Audio Input Audio Output Audio Output (L/R) Gain GAIN = VDD, Gain = 40dB； GAIN = GND, Gain = 50dB； GAIN = Vacant, Gain = 60dB。 A/R Activate/Release ratio, Control the AGC activate/release time ratio: A/R = GND: Activate/Release ratio = 1:500 A/R = VDD: Activate/Release ratio = 1:2000 A/R = Vacant: Activate/Release ratio = 1:4000 Specification * Operating Voltage: DC 3.0-5.5v * Board Wiring Pitch: 2.54mm * Phone Cable: 100cm * Speaker Cable: 30cm * Headphone Size: 13mm (D) * 5mm (H) * Board Dimension: 50 * 20 mm/1.97*0.79 inches * Weight: 36g Shipping List * Bone conduction speaker x1 * Speaker driver board x1 * 3.5mm earphone cable x1 https://elecena.pl/product/22723434/bone-conduction-kit-discontinued 2023-03-07 https://elecena.pl/product/22723434/bone-conduction-kit-discontinued 2024-09-19