Power supply: DC 3V-5V
Audio output amplitude: 950MV ± 50MV 47KΩ
EN Foot: The Bluetooth connection, output high (+3.3 V
Back to even function: automatic back even

Automatic control technology: 
1. search, matching, automatic ——- connection on the phone or computer can operate
2. signal input automatic switch ——- wired input seamlessly with Bluetooth input
When the Bluetooth connection is successful, the output is automatically converted to Bluetooth, Bluetooth disconnected automatically be converted to the cable input.
Module Parameters:
Bluetooth version: V4.0 + EDR
High quality Bluetooth chip Bluetooth version V4.0 + EDR
receives about 10 meters up to 20 meters without occlusion
PCB size 30* 30MM
Power3V – 5V
A set of stereo AUX audio input
A set of stereo audio output
a Bluetooth indicator
a Bluetooth status control output
Button Interface: 3 buttons, 2.0 Interface
Connect the equipments: 2

Module mutual process: 
KRC-86B Series modules, the power is automatically turned on, the status of AUX output
After the module is powered, automatic initialization, probably completed around 5s
After initialization, automatically connect back to the last connected device
After initialization, LED starts blinking
If the device is not connected to the last, the module automatically enters pairing mode
Namely: to search for other Bluetooth devices to this unit
The device name is: KRC-86B V4.0
After connection, LED from flashing to long bright output into Bluetooth output
Meanwhile EN pin output +3.3V High

Description of function keys: 
Power supply:
VCC: positive power supply (+3 V-+5 V)
GND: power supply is negative
LED:
LED +: pick-emitting diode anode
LED-: pick-emitting diode cathode

Audio signal:
AGND: audio signals received negative
OUTR: right channel output
OUTL: Left channel output
INR: AUX right channel input
INL: AUX left input

Key:
COM: Common keys
PLAY / STOP: sowing pull Pause
VOL + / NEXT: a short press, long press the volume increase
VOL-/REV: On a short press, long press volume down

Control:
EN: Bluetooth connection is high (+3.3 V), disconnect the Bluetooth is low
NC: Function Reserved

Note: NC pin must be left open, otherwise the module is not working properly, or damage to the module.
Specially designed AUX input: the original cable input
Function: wired and Bluetooth automatically switch
Bluetooth audio player connected to the Bluetooth
Disconnect the Bluetooth cable audio playback

Mobile phone bluetooth connection application
1, according to the product introduction correct connection, can be converted into the stereo speakers or DIY
2, open the phone bluetooth, bluetooth search point, shown as: KRC-86B V4.0
3, click: KRC-86B V4.0, cell phone began to connect, if you need the password, input and matching connection (invoice there is a password)
4, after the success of the device to connect, can use a mobile phone/tablet/other bluetooth devices play music, watch movies, play games