Radio without power supply? - radio power supply
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Take a radio receiver without the use of a power supply **. ** This can be done using an antenna, a trimmer, a germanium diode, which provides a low voltage cut, and a high impedance headphones, you can not load the track very much. You can test your design with a high-impedance headphones or external amplifier with input resistance. When the wind of its own antenna coil, you get extra credit. Its radius should be able to get clear at least one station.
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3 comments:
This type of radio is older than me, and I am over 50 years. They built these radios in 1920 and 30
Get a part # 22, or 20 threads, 2 would be better. Take out a box of Quaker Oats, and almost cylindrical wind back and forth with the cable. When I almost say that I am the thread of contact with his son. The ends must be held with tape, glue or hot glue. Wait until the glue dries before you continue. It's boring, but the additional point that will be useful. You need at least 4 mm wire free ends of the coil. Before you start this to get a piece of wood, 12 cm long and at least 6 inches wide. A piece of 1x12 would be good. Soft sand, and at least covered with polyethylene. The project will help you look good and a solid foundation for everything. Connection Clips are available at Radio Shack. Attach the rollers on the shelf. Driving a variable capacitor on the edge of the board, where the tree can be easily rebuilt. The impact of this capacitor is less than 365 PF. More than that wouldagree, but not less. A cable connects the coil to the capacitor structure. The other end of the coil is connected to the rotor plates of the capacitor and connect the antenna has a long cable. 100 meters of antenna cable and the maximum would be great. In connection point of the antenna coil and a capacitor, in conjunction with the anode of the diode. Connect a mobile driver's head until the end of the cathode of the diode and a building or the lower end of the capacitor. Turn the condenser and hear AM radio signals. The radios were in the 2nd World War I, and many other places where there is no power available. I'm sure a Google search will turn a scheme as if it were a search in at least the eldest son of pounds Scout Radio Merit Badge. Higher than in the years 1950 to 1960.
With respect to the germanium diode, "cut" really describes what the diode is not. The correction of the selected radio frequency into a vibrant, the powers of headphones. Germanium is used becausewith a driving voltage of 0.3 volts, making it useful for this project. If you really want to) Go for Gold ", a piece of lead ore (galena. Connecting to a page on a plate conductor, this would be one side of the diode. The other part is a beautiful piece of wire in place and that the free end is used to a place of management in the face of the ore, the provisions included the radio signal and is possible. This is the way were invented as before the diodes, and not LED tube for signal detection. Good luck with the project, well done, it will work. I built one or two in my past.