[Photo] GP antenna manufacturing method

The quarter-wave antenna in the industry radio should be regarded as the simplest and not bad antenna, so it occupies a considerable proportion in the radio industry. For example, if you pay attention, most of the antennas on police cars It is a quarter-wavelength antenna like the 430MHZ mobile phone you are using. Most of its antennas are also quarter-wavelength. Please note that most of the big mobile phones are also quarter-wavelength. The wavelength of the antenna shows that the quarter-wavelength antenna definitely has its effect. If you are not a concept of electronics, you may ask what is the quarter-wavelength? Simply put, it is an antenna The unit of length is calculated in terms of frequency. It has a formula:

The length of the antenna (wavelength) = 300 divided by the frequency multiplied by a quarter and multiplied by 0.96 (wavelength shortening rate) is

The calculated length of the antenna (in meters) For example, if you want to make an antenna with a frequency of 144.00MHZ, you must first calculate the antenna length and then use the above formula to calculate: (300 / 144.00MHZ) * 0.25 * 0.96 = 0.5 (meter)

So we get 0.5 meters, which is 50 cm in length. Then we need to prepare materials. We prepare 5 50 cm copper bars and an M-shaped connector (see Figure 1). Then use a soldering iron to connect the M-shaped main shaft to one of them. The copper bars are welded together, and the other four are screwed on the sides or welded, and the four are down 45 degrees

There is a relatively simple method of making GP antennas, and there are several methods of attachment.

The following is a physical photo quoting netizen "MXX"

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