This is a Do-It-Yourself homemade CB antenna.
This video shows some details regarding how I constructed the antenna.

Reflector element:
- Full length (94 + 23 + 94 inches).
- Larger outer pipe diameter = 7/8 inch (National Hardware N258-467).
- Smaller inner pipe diameter = 3/4 inch (National Hardware N258-442).
- Wood = 4 feet length. Other dimensions, I believe, are: 1 inch X 3 inch.

Driven element(s):
- Aluminum tube pipes = same size as tubes used for the Reflector element.
- Length of one side = 99 and 1/2 inches.
- Short distance between driven elements = 1 and 1/8 inch.
- Wood = same as wood used to support reflector element.

Boom:
- Length (spacing) between reflector element pipe and driven element pipe = 78 inches and 3/4.
- Wood = I believe it is 2 inches X 3 inches X 96 inches.

SWR:
1.6 on Channel 40.
1.0 on Channel 1.

Performance:
I am not an expert on antennas and performance testing nor do I have required equipment to perform detailed tests.
There are many variables to take into consideration for performing detailed tests.
I would think some example variables would be something like the following:
- coax length
- coax type
- antenna height
- antenna polarization
- antenna location
- etc

For (general) comparison, I have an Antron 99 vertical antenna (50 feet RG 213 coax).
The tip of the Antron 99 is about 12 feet higher than the dipole yagi beam antenna (75 feet RG 213 coax).
The Antron 99's location is outdoors, about 15 to 20 feet away from the dipole yagi beam antenna.

Locally (less than 50 miles), the Antron 99 performs about 1.5 S-units (tx/rx) better and audio (tx/rx) is generally better as well.
There was one instance where the dipole yagi beam received better than the Antron 99;
I assume that signal I was receiving was also horizontal polarization and/or it might have been within the strongest radiation path of the dipole yagi beam.
That day I was simply monitoring radio conversations and did not break into the conversation to ask about that station;
whether or not he was using a vertical or horizontal antenna.

In addition, all the regular local CB guys I talk to are not in direct line of sight
of the dipole yagi beam; they are actually about 30 degrees north.
They all use vertical antennas.

Notes on construction:
Initially, to construct this antenna, I was going to use wire. It likely would have cost less money to use wire, but I prefer working with pipe better.

I was going to use copper pipe (1/2 inch and 3/8 inch) but I had trouble finding rigid straight 3/8 inch copper pipe at local hardware stores. The aluminum pipe was easier for me to find at local hardware stores.

I first constructed a dipole by itself with No reflector.
I then adjusted the length of the dipole to achieve the best SWR as I could.
Then I took note of the result length (99.5 inches) of each side of the dipole.
Then, in order to determine the needed length for the reflector, I experimented with the antenna calculator website; the part where it says "3 element yagi".
I experimented with whatever frequency needed until the antenna calculator gave me 99.5 inches for one side of dipole length.
The frequency I used was 28.5 Mhz; this gave me 99.59 (which is close enough to 99.5 inches) for the length of one side of the dipole.

Summary of measurements:
Frequency = 28.5 Mhz (I am aware this is Not a CB frequency).
Driver one side = 8ft. 3 - 19/32in. (I rounded down to 99.5 inches).
Reflector = 17ft. 6 - 31/32in. (I rounded up to 211 inches).
Spacing = 6ft. 6 - 27/32in. (I rounded up to 78 and 3/4 inches).

(Regarding the reflector length; I might increase it about 1 inch to account for the 1 1/8 inches of free space between the the two driver pipes).

References:
Antenna Calculator:
[ Ссылка ]

Other References:
[ Ссылка ]
[ Ссылка ]
[ Ссылка ]

For the antenna experts out there, let me know if my measurements are way off.

Update February 5, 2020:
I have performed some preliminary testing with a field strength meter. I have compared the field strength with the Reflector element versus without the Reflector element. The field strength was stronger without the Reflector element. So, I think this means something might not be correct in my setup. I am guessing maybe the boom length needs to be longer.

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