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Note: The module chip model number is random; Different batches have different numbers
Special note: the module must be powered from the red 2P power supply seat, and cannot be powered directly from the USB power supply (here, it supports detection, and cannot drive the loaded high-power)
This product is a 5.2 BT TWS case matching function (optional); Support 4 euro 3w*2 or 5w*2 speakers; Support 3.5aux; Hands free call; 3pout output
The voltage is 5v/ the current is 2A. After secondary development of peripheral hardware, the maximum power can be configured to reach 5W. The Bluetooth device name is ymx-878bt
Power supply: DC DC voltage (3.7-5v) and current above 2a-3a;
USB socket is a charging input socket; When charging, the red light is on, and when fully charged, the red light is not on), please select lithium battery with protection board
Statement: The price is 1 pcs. If TWS function is used, you need to buy 2PCS, and two BT modules must be used (touch the key signal pin with the light switch or wire to contact GND grounding, that is, TWS is connected through mutual scanning; note that this is a touch, not a long press short circuit); The module can only have ordinary BT functions. When the board connected to TWS is mono; When TWS is disconnected, the board is stereo
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Operation method:
3P seat out output: external power amplifier board can be connected. The middle of 3p is audio ground, and the two sides are r/l respectively
3.5aux input: when the 3.5 audio cable is plugged in, it is the aux input mode (BT is disconnected); 3.5 the headphone stand cannot change the line randomly because it has the function of detection
Toll free call: automatically answer the call after the incoming call rings. The TWS function can only be used for calling on the motherboard
TWS pairing box: (touch the key signal pin with a light switch or wire to GND, that is, TWS is connected by mutual scanning; note that the touch is not a long-term short circuit). At this time, automatic pairing connection (after successful connection, there will be a "beep" sound, and at the same time, one board will flicker regularly / the other board will be on for a long time. Two PCBA BT modules must be turned on to operate this function. After scanning pairing, it will be connected automatically
About the main frame: two PCBA BT modules are used at the same time. If the host is disconnected (the blue light flashes regularly after pairing connection is the host, and the blue light stays on for a long time is the frame), the two modules are disconnected at the same time. After connecting to the mobile phone once, it defaults to the current host.
BT connection: turn on the BT detectability of the mobile phone from the setting menu so that the mobile phone can be detected by the device, and then go to the BT menu - search for devices or paired devices. After searching for the "touch pairing" of the ymx-878bt, you can also hear the "prompt tone" sound to complete the pairing;
Requirements for selection conditions:
Power requirements: Voltage DC DC voltage 3.7v-5v, and the voltage shall not be higher than 5V; Current 2a-3a; (special reminder: if you use a 3.7V lithium battery, please ensure that the lithium battery and discharge can reach 2A. Some lithium batteries have voltage but the current is unstable or can not meet the requirements, please use it with caution; otherwise, it will be restarted all the time or the sound quality will be poor, broken / distorted, etc.)
Horn requirements:
When the power supply is 5v/2v: (satellite) left and right channel speakers: select 4 ¥Ø /5w full frequency speakers
(special reminder: if you use a 3.7V lithium battery, please ensure that the lithium battery and discharge can reach 1.5A. Some lithium batteries have voltage but the current is unstable or can not meet the requirements. Please use it with caution; please choose to use 4 ¥Ø /3w for the horn
BT connection: turn on the BT detectability of the mobile phone from the setting menu so that the mobile phone can be detected by the device. Then go to the BT menu - search for devices or paired devices, search for "878bt" touch pairing "and hear the sound of" successful connection or prompt tone "to complete the pairing;
Note: if it is not a smart phone (Android system), enter the password -0000; Product BT device name 878bt
Special attention:
1) b+ is connected to the positive pole of power supply dc3.7v to 5v+, and gnd- is connected to the negative pole;
2) working voltage: lithium battery 3.7V, or regulated power supply DC 4.5-5v, current (1a when one horn is connected; about 2a-3a when two horns are connected). Lithium powered horn is equipped with 4 euro 3w+3w, and regulated power 5V horn is equipped with 4 euro 5w+5w. If the current is insufficient, there will be jump or unstable BT, the motherboard will be restarted all the time, or the sound quality is poor / broken / distorted (please check your power supply if there is this problem); The voltage should not be higher than 5V, otherwise the main chip, power amplifier IC and related components will be damaged, please note
3) Sp-/sp+ from bottom to top l-o-/l-o+ connected to horn
4£©Pay attention to anti-static treatment during DIY modification. The wire end must be in good contact, especially remember to turn off the power whenever you operate. The power supply can only be turned on after the wiring is checked correctly. Do not operate with power on. Don`t touch these points with electronic wires. be careful!