1/4 Wave Ground Plane Antenna

[dwmitchell61]

I made a home brew antenna today.

 

I built a 1/4-wave ground plane with 6 ground plane elements today. The SWR is a tad high at the higher repeater channels/frequencies (467MHz). The 462MHz channels/frequencies run a low SWR. 

 

I will try making the angle on the ground plane elements a bit steeper first. Then I will try trimming the element lengths, bit by bit.

 

This will be one of my "go box" antennas.

 

I may try a commercial made antenna with a ground plane kit I bought from here. I broke one of the ground plane elements, so will replace them with 12AWG copper wire. 

 

The quagi long-beam I built to use for reaching a distant repeater had very high SWR. It was scaled from a 440MHz antenna design. I need to rework the quad loops on it to match it.

 

Another project I want to build is a cubical quad "go box" antenna. So many projects, so little time... Trying to fix up our home to sell at the same time.

[dwmitchell61]

 

Forgot to click "Attach this file..." button.... Ugh 

[dwmitchell61]

I made a home brew antenna today.

 

I built a 1/4-wave ground plane with 6 ground plane elements today. The SWR is a tad high at the higher repeater channels/frequencies (467MHz). The 462MHz channels/frequencies run a low SWR. 

 

I will try making the angle on the ground plane elements a bit steeper first. Then I will try trimming the element lengths, bit by bit.

 

This will be one of my "go box" antennas.

 

I may try a commercial made antenna with a ground plane kit I bought from here. I broke one of the ground plane elements, so will replace them with 12AWG copper wire. 

 

The quagi long-beam I built to use for reaching a distant repeater had very high SWR. It was scaled from a 440MHz antenna design. I need to rework the quad loops on it to match it.

 

Another project I want to build is a cubical quad "go box" antenna. So many projects, so little time... Trying to fix up our home to sell at the same time.

Huh.... I checked the radiator AFTER soldering it into the center pin on the connector... It is 3mm to long... See what happens tomorrow as I go through teh steps above.

[mbrun]

Good Morning O-B-1.

 

Nice work on the antenna. Isn’t it amazing how simple it is to make a 1/4 wave ground plane antenna is? I have made versions for GMRS and amateur VHF. They tuned up quite nice. Love the low profile nature of the GMRS version. Did you use welding rods for yours?

 

When I was tuning my antennas I used a NanaVNA to help me visualize the effects on SWR & Impedance. I could see the effects of driven element length, angle of the ground plane, and proximity to other objects. What a cool instrument.

 

I see the picture shows the antenna close to the side of the house. Will you be raising it up above the roofline to improve coverage and eliminate the interference caused by the side of the house?

 

 

Michael

WRHS965

KE8PLM