Miniature Antenna Tower for Radio

Figure 1 

The project uses a 4-element Yagi-Uda and some blinking lights at the top for transmission to create a miniature antenna tower project.

The Yagi-Uda antenna is made of copper clad steel wire with 14 AWG for the vertical parts of the structure while the zigzag structure was made by wrapping around 18 AWG copper wire around s flat strip of steel. The coil is then stretched out so that it will resemble the zigzag structure of a real antenna tower. The 3 vertical pieces and 3 zigzag pieces were soldered together after being made followed by the thrust bearing plate and rotator plate that are made from small bits of PC board and some small coils of copper wire.

The circuit board used was made thin to fit between the box and the base tight. The flasher circuit was built around 555 and soldered to the box with a battery connector taken from a dead 9V battery. The active components include the triode, NPN BJT, bridge rectifier, P-channel MOSFET, diode, and pentode. The passive components comprise of iron core transformer, resistor, crystal, battery/DC power source, ground connection, antenna, electrolytic capacitor, inductor, and momentary/morse key switch.

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