Kit welding requires some electronic technology, please bring a multimeter and a soldering iron and other tools, manuals, etc. Our guide explained to prevail. Kit manual will be placed on the network for all to download. Dedicated to receiving calls between the aircraft and the tower, with the good performance of the antenna (VHF Yagi paragraph), open at the maximum acceptable within approximately 190Km between the various types of aircraft and the tower calls, like friends please pay attention. Has the following characteristics: 1. the package uses a band-pass filter, 3355 high-level, NE602 mixer, MC1350 programs in place, can receive 118-136MHz AM signal. 2. printed directly on the PCB trace inductance, greatly simplifying the assembly of difficulty, right after welding, the only devices that need to be adjusted in the week. 3. the board has to listen to the AGC circuit to ensure comfort, while avoiding the long squelch noise. 4.12 V power supply, PCB board size is 9.2 x 7.5cm, can be placed in 97 x 40 x 120mm aluminum chassis to use. Tip: Due to the VHF bands have similar propagation ---- rectilinear propagation of light, but the receiving location accessible from the airport, distance (greater than 25Km's) must be installed VHF Yagi antenna contour segment gain antenna; receiving location between the airport large obstructions (including but not limited to tall buildings, mountains, towers) is always around the obstacle, thank you! Colour:Green Material:plastic Package Contents: 1 * Air band Airband Radio Receiver Board (Unassembled) Only the above package content, other products are not included. Note: Light shooting 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.