0-2.4G All Band Antenna Full Band Antenna with 9.8FT Feeder Cable SMAJ Male Connector for SDR Radio

0-2.4G All Band Antenna Full Band Antenna with 9.8FT Feeder Cable SMAJ Male Connector for SDR Radio

Description:
This full-band antenna adopts a standard 1/4 wavelength counterpoise Brown antenna structure. Brown antenna counterpoise is widely used in professional fields such as airports, radio stations, and radar communication stations around the world. It boasts low standing wave, high efficiency, wide frequency band and excellent index effect. Through simple length adjustment, it can adapt to the transmission and reception of ultra-wideband radio signals in the range of hundreds of megahertz.

The antenna can set its optimal working center frequency for transmission by adjusting the length of the antenna, the length and the angle of antenna counterpoise within the radio frequency range of about 70-430MHz.

If it is only used to receive signals, the frequency band can be extended to 0-2400MHz. It can receive a variety of radio communication signals, including short wave, medium wave, FM broadcast, airport aviation communication, walkie-talkie communication, maritime communication, amateur radio communication, digital signal, and relay signal.

It can be used with a SDR wideband radio receiver. At the same time, it is also suitable for other radio equipment, including remote control, wireless alarm, remote control toys, cordless telephone, and digital communication.

It consists of 4pcs earth terminals, a choke sleeve square tube and a vertical telescopic antenna. When used for receiving, if you do not know the calculation and adjustment method of the antenna length and frequency wavelength, you only need to erect the antenna vertically, pull out the telescopic antenna in the middle, and tilt the antenna counterpoise downward in an umbrella-like angle of about 45 degrees. No special requirements. When erecting, a steel pipe or a wooden rod can be used to tie the stainless steel square tube of the antenna to erect the antenna vertically. The installation position of the antenna has a great influence on the effect. The higher the antenna position, the more open the center and the surrounding area, and the better the working effect.

According to the calculation of the theoretical formula of the antenna, it is known that the length of the antenna and the counterpoise should generally be set to about 1/4 of the antenna frequency wavelength. For example, when it is used for FM radio radio reception, it is recommended to pull out the 4 counterpoises. At this time, the length of the counterpoise is about 74cm/29.1", and the vertical antenna in the middle is also extended by 74cm/29.1". At this time, it is exactly 1/4 wavelength of the center frequency of 98MHZ in the 88-108MHZ frequency band of FM broadcast. If you want to use it as a radio receiving antenna in the aviation frequency band, according to the calculation, the pull-out size of the antenna and the counterpoise is about 59cm/23.2". At this time, the antenna resonates near the center of the aviation communication frequency band, and the receiving effect is the best. The specific setting appearance and frequency sweep test chart are shown below.

The length of the 4 counterpoises is generally the same as the length of the vertical antenna in the middle. The angle of the counterpoise is usually a downward slope of 45 degrees, and the specific length and angle can be adjusted during use or with the help of a meter. Usually, the higher the counterpoise angle is, the higher the antenna center frequency will be. When the length of the antenna and the angle of the counterpoise remain unchanged, shortening the length of the counterpoise will also increase the center frequency of the antenna. In actual operation, the length and angle of the four counterpoises can be different, so that different standing wave and center frequency effects can be obtained. In short, the 4 counterpoises can be adjusted in any length and angle. For short-wave signal reception, because the short-wave frequency wavelength is very long, for example, the length of the 1/4 wavelength antenna of 14MHZ signal is about 5.1m/16.7ft, so you can use copper wire to wrap the antenna and counterpoise, to further increase the length to better its reception effect.

When the 4 counterpoises are fully retracted, the length is about 15cm/5.9". When the 4 counterpoises are fully pulled out, the length is about 74cm/29.1". When the antenna is fully pulled out, the length is about 100cm/3.3ft. When fully retracted, the length of the antenna is about 20cm/7.9". The main body is a stainless steel tube with a length of about 33cm/13" as a choke sleeve, so that the signal current will not leak too much to the outer skin of the coaxial cable, which improves the transmission and receiving efficiency of the antenna. At the same time, the steel pipe can play a fixed role when erecting the antenna. No need for insulation, users can directly use steel pipes or wooden rods to tie the steel pipes of counterpoise together to erect.

The antenna is mainly used to receive broadband radio signals and is suitable for hobbyists with certain technology and instruments. If the antenna is used for transmitting, it is necessary to adjust the antenna, and the length and angle of counterpoise according to the 1/4 wavelength calculation formula and instruments to obtain the ideal resonance frequency and standing wave of the desired transmitting frequency. It is recommended that the transmit power be less than 20W.

It is a passive antenna and can be connected to an amplifier. When connected to an amplifier, it is an active antenna. We do not recommend using an antenna with an amplifier, because the amplifier indiscriminately amplifies all input signals, including noise, interference signals, and other unwanted signals. And the insertion of the amplifier will also cause the loss of some signals. If you want to use an amplifier, it should be installed near the roof antenna to amplify the signal received from the antenna that has not been attenuated by the feeder loss, instead of being placed at the end of the indoor feeder to amplify the weak signal after the transmission loss of the feeder.

Package Included:
- 1 x Telescopic Antenna
- 1 x Counterpoise with 3M/9.8FT Feeder Cable

Note:
- The outer diameter of the 50-3 feeder cable is 5mm and its connector is SMAJ male connector. Therefore, it is convenient to connect it to the SMA female antenna of most SDR receivers.
- If the feeder cable with other connectors is needed, please contact us before purchasing. Thank you!