Jungle Antenna Part 1
The Jungle Antenna
For the last several weeks you've heard me talk about a mysterious antenna known as the, "Jungle Antenna". The Jungle Antenna gets its name from its use during WWI, the Korean War, and the Vietnam War as it was used as a, "Field Expedient Antenna" for Radio Operators. Radio Operators recognized there was no one size fits all antenna once you get to the field so they learned how to build their own antennas based on the frequency they were going to be using. How? If you watched this week's video, you heard me mention the number, "936".
936 is the number we use to calculate the length of our antenna to make it resonant for the frequency we intend to operate on, based upon a full wavelength. For today's blog, we will be talking about 2 meters, or specifically, 146.520. So the first thing you will want to do is divide 936 by 4 since we are wanting a quarter-wave antenna which gives us a number of 234. Now that we know what a quarter of 936 is, we need to divide that number (234) by the frequency we intend to operate on. Now it does not matter which frequency you intend to use as this math will work for any frequency, but for today's blog, it is 146.520 (or simply 146).
234/146 = 1.602739726027397 (DON'T ROUND YET!)
Now we want to know what this is in inches, so we multiple this number by 12 (12 inches in one foot).
1.602739726027397 x 12 = 19.23287671232877
Now we can round the final number which will look like;
19.23 inches. This is the final (don't cut the wire yet) length of the wires for the Jungle Antenna. You'll need to add a little more to the wires to secure each end of the wire to the 550 cord and the opposing triangle. I would cut the wire for 20.23 inches, but make a mark on the wire at 19.23 once everything is assembled. Now, let's look at the rest of the components.
You will need the following items;
50' of paracord (550 cord)- https://amzn.to/2DcTWSa
18 guage Primary Wire- https://amzn.to/3iyXSwI
SMA Female to BNC Female Adapter- https://amzn.to/31OAULV
Ring Terminals- https://amzn.to/2VR5yk2
Banana Posts- https://amzn.to/2BwU0f9
25' RG-58 Coax- https://www.ebay.com/itm/US-MADE-25-FT-RG-58-BNC-Male-to-BNC-Female-50-ohm-coax-cable/113883152146?hash=item1a83f6ff12:g:R2AAAOSwP6pZok1N
Make sure your RG-58 has one BNC Male and one BNC Female for this project. As you experiment, you may look at different types of coax, but make sure your coax is rated for 50 ohms and has a stranded center conductor. The 18 gauge primary wire needs to be stranded wire as well; don't use solid.
Now that you know what the components are, keep an eye on Part 2 where I show you how to assemble the Jungle Antenna and make it work.
Thank you to all my loyal readers and viewers. If you are enjoying this content, would you mind sharing this with your friends? Don't forget to check out our YouTube channel and Social Media accounts.
www.youtube.com/c/tacticalcomms
www.facebook.com/tacticalcomms
www.instagram.com/tacticalcomms
For the last several weeks you've heard me talk about a mysterious antenna known as the, "Jungle Antenna". The Jungle Antenna gets its name from its use during WWI, the Korean War, and the Vietnam War as it was used as a, "Field Expedient Antenna" for Radio Operators. Radio Operators recognized there was no one size fits all antenna once you get to the field so they learned how to build their own antennas based on the frequency they were going to be using. How? If you watched this week's video, you heard me mention the number, "936".
936 is the number we use to calculate the length of our antenna to make it resonant for the frequency we intend to operate on, based upon a full wavelength. For today's blog, we will be talking about 2 meters, or specifically, 146.520. So the first thing you will want to do is divide 936 by 4 since we are wanting a quarter-wave antenna which gives us a number of 234. Now that we know what a quarter of 936 is, we need to divide that number (234) by the frequency we intend to operate on. Now it does not matter which frequency you intend to use as this math will work for any frequency, but for today's blog, it is 146.520 (or simply 146).
234/146 = 1.602739726027397 (DON'T ROUND YET!)
Now we want to know what this is in inches, so we multiple this number by 12 (12 inches in one foot).
1.602739726027397 x 12 = 19.23287671232877
Now we can round the final number which will look like;
19.23 inches. This is the final (don't cut the wire yet) length of the wires for the Jungle Antenna. You'll need to add a little more to the wires to secure each end of the wire to the 550 cord and the opposing triangle. I would cut the wire for 20.23 inches, but make a mark on the wire at 19.23 once everything is assembled. Now, let's look at the rest of the components.
You will need the following items;
50' of paracord (550 cord)- https://amzn.to/2DcTWSa
18 guage Primary Wire- https://amzn.to/3iyXSwI
SMA Female to BNC Female Adapter- https://amzn.to/31OAULV
Ring Terminals- https://amzn.to/2VR5yk2
Banana Posts- https://amzn.to/2BwU0f9
25' RG-58 Coax- https://www.ebay.com/itm/US-MADE-25-FT-RG-58-BNC-Male-to-BNC-Female-50-ohm-coax-cable/113883152146?hash=item1a83f6ff12:g:R2AAAOSwP6pZok1N
Make sure your RG-58 has one BNC Male and one BNC Female for this project. As you experiment, you may look at different types of coax, but make sure your coax is rated for 50 ohms and has a stranded center conductor. The 18 gauge primary wire needs to be stranded wire as well; don't use solid.
Now that you know what the components are, keep an eye on Part 2 where I show you how to assemble the Jungle Antenna and make it work.
Thank you to all my loyal readers and viewers. If you are enjoying this content, would you mind sharing this with your friends? Don't forget to check out our YouTube channel and Social Media accounts.
www.youtube.com/c/tacticalcomms
www.facebook.com/tacticalcomms
www.instagram.com/tacticalcomms
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