Transmitter: I. Button control and LED indicators: 1. Green indicator 4pcs are power indicators, they are: 0.1mW(0)/25mW(D)/200mW(C)/800mW(H).(D)/200mW(C)/800mW(H), the default is 0.1mW when the power is on. To power level. This operation can be cycled and the corresponding power indicator will every time you press and hold the button. The corresponding power indicator will each time you press and hold the button. Note: The transmitting power must be readjusted after each power failure. The 9 red indicators are the frequency point indicators and are switched to frequency point by pressing the button once. This operation can be cycled, each short press on the corresponding frequency point indicator will .Note: The has a memory function, the system will save the current frequency point after power failure. Interface definition: The antenna is SMA interface; the antenna head is "male thread + hole" and the antenna pole is "female thread + pin"."Pin" configuration 1.2G special customized "Y" type antenna. The sequence of the socket connection is: 1. power input DC 7-28V; 2. input ground; 3. video input; 4. 6.5M audio input; 5. DC output 7-28V; 6. DC output ground; 7. DC output 5V. Set Type: C Material: PC+metal colour: black Package Contents: 1 x Transmitter 1 x Receiver(Factory slightly different) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.