Mobile UHF Antenna Kit w/Fibreglass Antenna

Mobile UHF Antenna Kit w/Fibreglass Antenna

The CL474S is one of the most popular UHF CB antennas as it has great gain and short length.
The CL474S is a fiberglass collinear antenna with 3.6m coax & supplied with a pl259 connector.
It is available in white or black and has a shock absorbing spring with a 1/2" UNF stud that can be mounted almost anywhere on a vehicle.
It does not need to be earthed and can also be used as a mini base antenna.

SPECIFICATIONS

Length: 950mm

Gain: 4.5dBi

Description: White Fiberglass Colinear UHF Antenna

Frequency: 474MHz ~ 479MHz

Most high gain - Collinear Antennas are DC Grounded and do not need tuning

DC Grounded means the antenna has what is known as a LC Network, Tuning stub or similar method for matching the antenna in order for it to work on the frequency required, what this means is that if you were to measure the connection at the base of the antenna with a ohm meter it would read a DC dead short (DC Grounded) - This is normal and is a common way of designing antennas. DC Grounded antennas do not need a ground plane or earth as in the case of monopole antennas;

Do's & Don't with DC Grounded Antennas

DO - Test for shorts or open circuit if possible with an multimeter or SWR with a SWR meter. When a DC grounded antenna is tested with a ohm meter the reading is a short circuit or around 3 Ohms at the base, this seems strange but it is correct!. It is important when testing the cable that the cable is not connected to the antenna or to the transceiver! If in doubt please call. Testing the antenna ensures all is in working order including the transceiver

DO - Mount the antenna high as possible - Bull bar is often the best place for this style of antenna

DO - Use a spring if mounted on a bull bar. The spring is important to absorb the vibration from the engine, without the spring the antenna eventually may fall apart!

DO, DON'T - Earthing the antenna at its base, doesn't matter - It makes no difference to performance

DON'T - Mount the antenna along side any metal object - As far away as possible
Any metal object will absorb the radiation from the antenna, greatly reducing its performance, you need at least 700mm from a wall or from another antenna for 477MHz antennas, if this is not possible then mount the antenna as far away from any other antenna or metal object as possible.

(M1CL474KIT)