Homemade remote control dual mode receiver ---- Receiver transformation

Author: Song Xiangqiang The dual mode receiver can receive both the nine live star signals and receive a normal DVB signal, and simply switch between the two modes, it is very convenient to use. The test equipment is the Nine Machine and Zhongda Sapphire Free Machine (hereinafter referred to as Six), which uses the Qilida chip, cut off the power supply in the standby, and uses this feature. Control the opening and closing of nine machines, thereby reaching the "dual mode" purpose, the principle is shown below. In the drawings, KC1 and KC2 are relays, and KC1 control tone treatments are selected from one output, and KC2 controls nine machines. The VD and R constitute a voltage regulator circuit, and supply the polarized voltage of 13V / 18V on the feed line to supply the relay. The principle is to control the audio and video output using the medium-sixth machine feeder voltage. Be Welding circuit board, although the four-pin is used, but only two ports are used, and the voltage supply relay in the medium feeder is achieved. The regulator element uses a 12V regulator diode and a partial voltage resistance of 600. The relay KC1 employs a 12V double-knife double-throwing relay, two nine-nine-nine-nine-machine AV terminals, normally open contacts, and the public end AV output socket. KC2 uses a 12V single-knife relay with a contact voltage of 220V and is connected in series with a Chinese motor power source. The outdoor antenna connection only requires the nine live star to connect to the position of the four-cut port 1, and the ports 2 to 4 are connected to other satellites. The feeder is connected to the antenna jack of the machine. After connecting the line, turn on the power switch of the Six-machine and Chinese. At this time, the middle six machine is working, the Chinese nine machines do not work, in which the dual mode can be achieved. Be Be When pressing the "standby" button on the middle and six-machine remote control, the six-machine enter the standby state (the machine digital tube display OFF), the feeder voltage disappears, the relay contact is reset, connected to the nine lines, and the middle and nine machines work into the middle Nine mode is watching live stars (Figure 4). When you press the "standby" button of the middle six, when the Six plane is wokep, the relay is electrically sucked, disconnect the nine-machine line, and enter the six-mode to watch DVB free program. This is the DIY dual mode machine, the "standby" button is the switch button. When the end is closed, just close the power of the two machines. With this method DIY dual-mode machine, the biggest advantage is that no change in the machine, retains all the functions of the machine, but it is to switch to "cost", from energy saving low carbon perspective. Very scientific, if it is improved, use the standby signal of the machine chip to achieve both interlocks, this is the true dual mode machine.