2m Quarter Wave Amateur Radio Antenna DIY

in Anarchism4 years ago

In my hiatus from Hive, I've been meeting new folks and making new friends. Stupid pandemic lockdown can't keep a guy down. There's things to accomplish with seven weeks off work!

I got plugged in with a group of guys that are interested in developing skills for networking, usefulness, and survival. Things like gardening, knife throwing, bushcraft, natural medicines, first aid, shooting, and the like. Since I have my amateur radio license and some basic knowledge on the subject, I'm the radio communication guy.

As such, I'm developing a comms program for us and encouraging the other guys to get their licenses and develop some basic understanding of radio.


Did you know there's ways to plug your phone into a radio and use it to send texts and data packets if the cell grid goes down?


I got my radio license some years ago, and haven't done much with it since. I'm glad to have a reason now to get into it, as it is a good skill and a fun hobby to get into. My first project with my new network is to build an antenna for myself and my closest brother. The radios we have, Baofeng UV82's, operate on the 70cm UHF and 2m VHF bands. Between the two, 2m has the best range, so that's what I'm basing our antennas on. We have a local ham radio repeater about a mile and a half away that I can probably hit with my stock antenna to communicate with my friend, but that would be too easy and I wouldn't have a project. Not having a project isn't an option.

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So after a little research and a birthday gift from my mother in law of $50, parts were ordered!

For materials, I ordered:

  • Two SO-239 chassis mount connectors ($8)
  • Two 20' (7m) lengths of RG8X coaxial cable with male PL-259 connectors ($33)
  • Two SMA female to SO-239 female adapters ($8)

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SO-239 connector on the RG8X coaxial cable

At my local hardware store, I picked up:

  • Solder ($10)
  • A soldering iron ($20)
  • some # 6-32 screws and nylock nuts ($3)

I already had some 3/32" aluminum welding wire to use for the radials and radiator, so I opted to use that instead of copper or brass. That saves money and time. You can even use a wire coat hanger for these, just scrape off any paint so you get a good electrical connection.

The hardest part was soldering the radiator into the chassis mount adapter. It wasn't hard when I got Sam, my oldest, to hold the wire on the pin while I did the soldering. When I tried the first time, I found out fast that my late father in law's old soldering iron just didn't get hot enough for that big of a project. I had to buy another one, which is fine. It'll come in handy for a lot more projects in the future.

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SO-239 connector with a mock-up aluminum wire radiator

After the parts cooled, I twisted the ends on four more wires to accommodate screwing them to the holes in the chassis mount. When they were screwed on, I used my phone to calculate that the radials and radiator needed to be 19.23" to resonate on the 2m band. Sam and I measured the wires and snipped them all on both antennas and they were done!

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Completed antenna!

I'm waiting on the adapters to come in so I can test the antennas, and they'll be set up at our houses this weekend! A fun little project that's helping me connect, network, and build skills with like minded folks during this dumb lockdown.

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Close-up of the completed assembly

I hope someone finds this useful and empowering. The prices I gave are not at all the cheapest route for an effective ground plane antenna. I'm going to be posting more of these types of projects too for more applications and situations. Thanks for reading, I hope you can benefit from it!

Much love,

Nate

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I am a new ham and have been chatting with other members of the local ham radio club larc.ca. We chat thru a local repeater every Tuesday night. It is call an Elmer net where us noobs can chat with more experienced ham's. I have a Yaesu FT-60 my brother gave me and would like an antenna on the roof for better range. I might even try building this.

I have cross posted your post to Ham Radio Community.

Hey, thanks! I really recommend it for a project. I dropped a pic on a FB ham group, and there's guys on there that did some AWESOME things with this little antenna. I'm gonna follow the ham group now, thanks for pointing it out to me!

Interesting and I have been thinking about getting a baofeng. They hands down have the best reviews by everyone, even those that prefer to only buy American products.

Is your license a lifetime one?

I really want to start building my own data tower and try to get more ppl to do so, so we don't need big corps to be able to use the air waves. This seems like a good start.

Baby steps😀

That's the spirit! Decentralized communication!

Absolutely recommend a baofeng for a starter radio. What I'm finding is that when I get more well versed in comms, I'll want something more. But there's no other radio out there for that price, so it's hard to bash em.

The license is good for like ten years. I don't know exactly, but it's a while. I'm not the type to advocate for a licensing process, but it really opens a lot of doors to get the license.

As for a tower, they can be built or bought. Check FB messenger, they're pretty affordable actually. I saw one that was $50 per 10' section. Sounds like a lot when you get up really high, but you're building a tower for crying out loud. $5 a foot is pretty good. Of course, you can just strap the antenna to your roof or hoist it in a tree or stick it on a pole in the ground for a lot cheaper too. Lots of options.

I have 2x BF UV-9R Plus and a BF UV-5R. I'm using the 9R+ for kayaking as they are waterproof. In Australia, the CB is FM so I can use the public channels. The 5R is mainly used in my car with a handheld speaker.

Thank you for the valuable information my friend.😀

How do you like the 9R? I'm thinking I need one lol

Got them for about 10 months now, still working fine.
They are bulky but work good. There are less accessories for them than the 5Rs. You will need to get the correct USB cable if you want to program them with a software on the computer but you can also program them using the built-in keyboard although a bit more painful if you have many channels to enter.

Yeah, I've got the cable to program. I worked up a program of local repeaters for my group of guys to use.

What I meant is if you have a 5R you would need another cable for 9R+ Not same connector

Ohhh, okay! Damn, that's a whole nother expense lol

Maybe one day. Our local 2m channels plus murs/frs/gmrs is 120 channels.

This was one of the first antennas I made when getting started. Works great but won't last very long in the field.

Oh yeah? What makes it less durable? Just the light construction?