A homebrew coaxial Collinear antenna for 2m （１４４MHｚ帯コリニアアンテナ）

 1. Overview
     This antenna is very easy to make with 50 ohm coaxial cables. The costs are practically low if it is made from surpluses of 3D2V (50 ohm cable). The performance of this antenna is very good with the specified length on 2m band.

2. Design
    Dimensions are shown in the photo of the antenna.

Finally the antenna is put in PVC tubes...

It is a fixed antenna for home use and also a mobile antenna for out-of-doors.

3. VNA measurements

The resonant frequency is 145.4 MHz at VSWR of 1.39. The band width below VSWR of 1.5 is about 1MHz (145.0 - 146.0 MHz).

4. Simulation analyses (with MMANA)

This has proved to be a good antenna. The gain should be about 9dBi and has a very low angle of elevation of 3.5 degrees.

4. Conclusion

I have a plan to use this antenna for emergency radio communication. This provides a radio communication network capable of being constructed/utilized at an extremely low cost.