VHF 5/8 Bottle antenna

Hello everyone today, I’m publishing a story about how to create a simple antenna with inexpensive materials.

Push more for details.

For a long time I was looking for a type of VHF antenna that would not need turning works. On the network there are two variants of one design.

http://hamnv.narod.ru/58but.htm

http://cqra1tbh.ru/my_app/ant/index.htm

So, we will keep the basic idea of ​​the design, but we will do all of the things that left after the house repair and from the building supermarket .

As a basis, he took a part of plastic cornic

As a vertical, two aluminum pipe with a diameter of 10mm and 6mm were bought.. each length 1m They can be inserted into one to other, but I made a clamp to fix the length, it will further help us to adjust antena resonance. To the top of pipe , I make the plug to prevent inside of antenna from moisture.

The vertical was fixed on the basis of bolts and bits of 1,5 mm textolite

Counterpoises made with a 6 mm diameter power wire. I had pieces of 1010mm in length. I turned them in half and made a loop that could be secured with a M6 bolt.

Connector SO-239 is fixed on the corner bent from brass sheet 1.5 mm and bolted with a bolt that holds counterpoise.

The coil is wound on a 1 mm wire on a plastic tube of 16 mm

You can use the case from the permanent marker, it also matches the diameter.

 

We need to wind up 9 turns of the lower contact of coil, fix on the bolt that holds the counterpoises, the upper coil contact contacted to the vertical.

The central output of the SO-239 connector is soldered to 3 1/3 wind of coil from the top (from the vertical).

Antenna adjustment is better to do using an antenna analyzer, but I only have a SWR meter.

The method of adjusting of SWR is in changing vertical length for minimum SWR, and then compress or stretch the coil to make SWR more lower as much as possible.

If the above manipulations do not allow you to lower the SWR below 2.0, try solder the central output of the SO-239 into another position on the coil.

In the resulting position, the coil is fixed by cable ties.

In my case, KSX turned out to be 1.3, this result of KSH for 5/8 confirmed another radio amateur.

To protect against precipitation, from the top, wear a 2-liter PET bottle from beer.

In the future, the antenna will be attached to the wodden mast and installed on the roof.

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