Antenna

The antenna is a simple 2 meter half wave dipole. I created a PCB that would accommodate either soldered elements or elements attached via SMA connectors.

They look like the following:

antenna_01

Here is one built up using soldered elements:

antenna_02

The elements consist of copper coated steel wire (.062″) used for welding.  The copper coating makes it possible to solder to a PCB. I initially built the elements slightly long so I could tune it up by trimming.

Luckily, I have access to a network analyzer which I used for testing and tuning. Here it is hanging from the VNA:

antenna_03

and here is the initial scan:

antenna_04

Marker-2 is set to the desired frequency of 144.4 MHz, and marker-1 is set to the initial resonant point which turned out to be approximately 142.0 Mhz.

After trimming, the final results look pretty good for this simple antenna:

antenna_08

 

 

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