DC 3V-5V FM Transmitter Module DSP PLL 87-108MHz Stereo Digital Wireless Microphone Board Multi-function Frequency Modulation |

DC 3V-5V FM Transmitter Module DSP PLL 87-108MHz Stereo Digital Wireless Microphone Board Multi-function Frequency Modulation |

1. Product Introduction:

1>. Output Power:100mW

2>. Audio Frequency Response Range:50Hz-18KHz

3>. Transmission Frequency:87.0MHz-108.0MHz (campus broadcast power off);76.0MHz-108.0MHz (campus broadcast power on)

4>. Frequency Adjustment Stepping:0.1MHz/times (short press the key);1.0MHz/times (long press the key)

5>. Modulation Mode:standard FM

6>. Sound Track:LINE/USB channel (stereo);MIC channel (single channel) 7>. Equivalent Noise:>=30dB

8>. Power Supply Voltage:DC 3.0V-5.0V 9>. Operating Current:35mA

10>. Adaptive Antenna:75cm bar antenna

2. Application:

1>. FM Wireless Frequency

2>. USB PC Audio Broadcast

3>. Wireless Microphone

4>. Maternal And Infants Custody

1>. Power supply

The corresponding port of the module "-", "+" respectively connects the power (battery) negative pole and the positive pole. The power supply is recommended for battery or other stabilized power supply.Do not use an unfiltered power supply (such as a mobile phone charger and other low-quality switching power supply), otherwise the interference of the power supply will affect the normal work of the module.The normal working voltage of this module is 3.0-5.0V, and the power supply voltage should not exceed this range.

2>. Buttons

Volume +/- : short press volume +/- 1, long press continuous +/-.

Frequency +/- : short press frequency +/ -0.1mhz, long according to continuous +/ -1mhz.

Mute: short press to switch mute/non-mute.

3>. Antenna

The ANT port is used to connect the FM antenna. In order to better transmit the FM signal, it is recommended to extend the antenna with a length of 75cm. And the antenna is near as far as possible without obstruction.

4>. USB audio connection

If you want to start the USB audio broadcast function of this module, you need to connect the USB cable to the computer. USB port is compatible with common cell phone, so you can use the USB cable to connect the module and computer. Because computer USB comes with 5V output, USB connection can be used to supply power to the module directly. After connecting to the computer USB, the module will automatically enter the PC audio broadcast mode, the LCD screen will display the PC, the computer terminal will install the driver automatically, and the module will be named "CD002" sound card device. Enable this "CD002" audio device in the computer voice Settings. Computer system audio can be transmitted through this module by FM. When the radio frequency is adjusted to the frequency of this module, the audio of the computer terminal system will be heard.

5>. LINE audio connection

If you need this module LINE (line in) channel as a source of sound emission, please insert one end of the audio LINE into 3.5 mm audio jack of the module , insert the other end into your audio device (such as mobile phone headset hole), the module automatically switch to the launch of the audio source LINE channel as FM. The nearby FM radio can be heard from the mobile phone as long as it is tuned to the same frequency as the module.

6>. FM wireless microphone

If you need MIC of this module to launch, pull out LINE and USB cable (LINE and USB are not connected). The module is automatically transferred to the MIC channel as the transmitting audio source of FM. This module is equipped with a high sensitivity electret microphone, which can be used in wireless microphone, mother-baby monitoring and so on. Note to adjust the volume of this module to achieve the optimum sound pickup effect when used.

7>. Serial port control (please ignore this part without serial port control)

The module reserved TTL level serial port control interface.When TTL serial port communicates with this module, it needs to connect the module's UART_RX, UART_TX and GND.You can use the external MCU or the computer serial port to send instructions control module related functions.

Note: The computer serial port is not TTL level. When connecting to the computer communication, it is necessary to connect the RS323 level to the TTL power leveling device or to use the USB TTL level serial port module to communicate with the module. Serial command control module requires certain computer expertise, if you don't understand, please don't try.

1>. Setting of backlight LED mode

When the power is off, press the “FRE-” and “FRE+” button at the same time to start up. B1 indicates always bright. B0 indicates that the backlight is closed for 20 seconds, and the reset setting takes effect. (the factory defaults to 20 seconds of backlight delay).

2>. Start/close the campus radio frequency band

When the power is off, press VOL+,VOL- key, and power on.LCD display C1, which means to start the campus broadcast.C0 means closing the campus radio frequency band.Set to take effect after restart. (the factory defaults to closing the campus radio frequency band).

3>. Settings of stereo/mono transmission mode

The back of the module has two solder joints M,G. Short connecting is the monophonic launch. Disconnecting these two points is the stereo system launch. (the

factory defaults to stereo system launch).

Note: the stereo system must satisfy the input to the module's audio source is stereo and the radio is also stereo to achieve the stereo effect. When using a single speaker (monophonic) radio or input to the module's audio signal as mono, there is no stereo.

1>. The power supply voltage is strictly prohibited to exceed the power supply voltage range of this module.

2>. Do not touch the back part of the module when working, so as not to affect the normal work of this module or cause the short-circuit burn module.

​

This module can set the backlight state and whether to listen to the campus radio frequency band according to the user's specific usage.

FM transmitter instructions

power supply  
1. The module has a Micro USB interface and can be powered by a computer USB.
2. The corresponding ports of the module (marked on the PCB board)-and + are respectively connected to the negative and positive terminals of the power supply (battery). The power supply is recommended to use a battery or other regulated power supply. It is not recommended to use switching power supplies without filters (such as mobile phone chargers, mobile power supplies, and other switching power supplies), otherwise the interference generated by the power supply will affect the normal operation of this module. The normal working voltage of this module is 3.0-5.0V, and the power supply voltage should not exceed this range.
To
Antenna
The FM_ANT port is used to connect an FM antenna. In order to better receive FM signals, it is recommended to connect a 75cm-length whip antenna.
To
Line input: You can use the 3.5mm standard audio plug to input the stereo sound signal. If no plug is inserted, the microphone signal is automatically picked up (the microphone signal is on the left channel). USB audio signal input is also possible.
To
Volume adjustment
Press VOL—or VOL+ to adjust the volume, and the LCD screen displays the volume level.

Frequency adjustment
Press VOL- or VOL+ to adjust the transmit frequency, short press +-0.1MHz, long press +-1MHz, and the LCD screen displays the current frequency

Mute
Short press the PAUSE button down to switch mute/non-mute

Connect to the serial port (no need to connect if you don't use serial port control)
The module reserves a TTL level serial port control interface. The communication between the TTL serial port and this module needs to be connected to the module's UART_RX, UART_TX and GND (the corresponding position on the PCB is marked), and the external MCU (microcontroller) or computer serial port can be used to send commands to control the module. Features.

For specific serial port commands, please refer to the document "FM Transmit AT Command List"