My first home brew antenna - 2m 1/4 wave ground plane
imgur.com/a/ubvt0
imgur.comPosted Feb 14, 2017, 4:54 AM UTC
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imgur.comWell now you've done it. Build one homebrew antenna and the next thing you know you're spending your lunch money on antenna making supplies, and looking around for parts and pieces that can be recycled into a working antenna...you are done for...once the bug bites, it's over.
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Haha I've already been looking at making something for the HF bands, now that I saw what this one could do. I'm planning to buy an FT-857D once I get my tax return back, so naturally I'll need an antenna, right? And if I can save a little money by making another home-brew, all the better. Luckily my wife has been very understanding and supportive of my new hobby!
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Here's the text from a sign spotted in someone's shack:
"My XYL told me she'd leave if I didn't stop scrounging parts for antennas. I'm sure going to miss her carrying the boxes of stuff from the car to my workbench."
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I bought a portable J-pole to get a little better signal out of my HT but it was still a bit spotty on the more distant repeaters, so I built this. My first home brew, and it hits a repeater over 30 miles away across some pretty mountainous terrain. I'm definitely happy with it! Elements are 12 gauge copper wire connected to an SO-239. The mount is 3/4" PVC, clamped to my balcony for quick and easy setup/take down.
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If you can find 3/16" copper pipe, it also fits around the center pin of an SO-239 as well. I had difficulty finding stiff enough wire to use as the radiator. I placed some solder in the cup of the SO-239 and put the pipe over top, heating the assembly with a propane torch caused the solder to melt and it was perfect.
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Good to know - thanks. The 12 gauge insulated copper wire seems to be working well for me so far, but I'm sure copper pipe would be even stronger.
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Very nice! Those were the first antennas that I built as well; a 2m and 70cm ground plane. I think I still have the 70cm ground plane as it is nice and compact.
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Coat hangers?
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No, it's about 10 feet of 12 gauge insulated copper wire from the local hardware store. I cut five lengths of 20 inches each, stripped an inch or so off the end for the connections, then trimmed for resonant length.
12 gauge wire is great because it's strong enough to hold its shape at these lengths, yet flexible enough that I could roll up the whole antenna for transport if necessary.
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If you have spare romex around (house wiring), it's pretty much the same stuff. I happen to have a bunch left over from some house wiring projects, and a 2m ground plane antenna is on my to-do list.
Nice work on this, you've inspired me to move it up my list and get it completed!
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Yeah, pretty much any copper wire should work. I rent an apartment, so I didn't have any romex lying around but the wire I got at the hardware store was pretty cheap.
Good luck on your antenna!
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This was my first diy antenna too. I used a plastic cup to help cover the pl259 from the elements. The setup was far better than the rubber duck on my HT. Congrats and keep going! It only gets more fun from here.
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Thanks! That's a good idea for a little weather protection. I didn't expect much from the rubber duck on my HT, but thought the portable j-pole would do better than it did. This home-brew 1/4 wave gives me far better performance than either one, and the materials were pretty cheap.
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Looks good. I literally built the exact same antenna 2 years ago. Same way with a PVC riser to hold it up. Still works great. No problem hitting the repeater 30 miles away
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Nice, glad to hear yours is still going strong. I got the idea from K7AGE, who has a helpful tutorial video on YouTube: https://youtu.be/HkmD3Sgz7Q0
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Very good. Used to have one of those hanging in the living room in college. Last November we moved into a house after the weather got to bad to work outside. There is one hiding in an upstairs closet right now.
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Nice - are you still using it from the closet?
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Hehe, yep. That won't change till the weather gets nicer. Then I need to deal with getting a lot of coax out through the wall. I just have one piece of coax going out to a G5RV now.
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Hey, so long as it works! Since I'm renting an apartment, I couldn't drill holes in the walls for coax. I just set up the antenna on the balcony when I'm going to use it, and run the coax in through the patio door. I can't fully close the door while I'm operating, but it's not too bad.
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In Minnesota you want that balcony door closed in January and February! Well, normally. Today it's 40f instead of -20f. We're finally out of apartments. The first five years we were in an RF noisy and RF shielded apartment. I still made a few contacts. I was able to get RG-58 to wiggle through the wall air conditioner located next to the balcony door. I had a Hamstick dipole mounted out there. The last year we were in a 3rd floor apartment that had less RF shielding and less noise, but the balcony was in a corner and the dipole didn't fit so it sat on top of a bookshelf in the bedroom. Hey that 6 meter dipole on the wall in the second apartment worked Colorado from Minnesota with 25 watts.
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I also made one of these. I painted it green and put a hook in the top so I could hang it in a tree for foxhunting. The green paint partially flaked off revealing the brown copper underneath it. It blended really well with the foliage. So well, in fact, Victor pissed on it because he didn't see it.
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Nice! We make these in our "new hams meetings" every now and then. SO-239 and a little bit of romex (maybe some caulk or shrinkwrap to seal it)
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Yeah, I wish I'd known about this antenna design when I first got my license. It's pretty simple but works really well. Couldn't be happier with it so far.
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Nice looking place you live in.
Now put a 1090MHz version up for plane spotting too!
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Thanks - I've been in northern New Mexico for almost a year, and I still can't believe how beautiful it is here.
Plane spotting sounds pretty interesting. I knew about pulling data from weather satellites, but it never occurred to me that you could do the same from plane transponders. I haven't gotten into SDR yet, but with cool stuff like that to do with it, I think I might have to someday.
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You're already half way there with the antenna. You have two options for plane tracking, ACARS on the VHF airband, or ADSB in the L band. Both are very easy to setup and your VHF antenna will likely be more than adequate for receiving ACARS but listening to ADSB is an excuse for more antennas!
Check out PiAware, I'd personally recommend putting F type adapters on both the antenna and SDR just because RG6 is very low loss compared to other options.
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Interesting - thanks for the tip!
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Put some tape or shrink wrap on the ends of the wires. They are eye seeking pokey bits. On your next build, cut the elements a little long and fold them over to make blunt ends.
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I read about the ends-folded-over method, but ended up just doing the elements straight. Having the ground plane elements folded down 45 degrees at least helps keep the ends out of eyes.
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Nice view
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What are you using to keep the center element from tipping over?
I have made one out of 8ga romex, but due to some rough handling in deployment setup the element likes to strain when tipped and break the solder joint.
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After I soldered the joint and let it cool, I just wrapped the connection in some electrical tape to give it a little more support. I'm not sure how much rough handling it will hold up to, but so far it's holding up well.
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8ga was too big for the SO-239 pin so I had no support there. At worst, I should find a thinner wire for that antenna.
I need something more than a roll-up j-pole at the moment and have had this semi-portable ground plane made, but that center wire kept breaking when I would work on the mount for a location.
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Ah, that makes sense. Yeah, the 12 gauge insulated wire is a great fit with the SO-239 - I'd recommend giving that a try.
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Thanks, I'll keep an eye out for that to fix my work. I always got better reports with a 5 rod ground plane attached to an HT (when that's all I had for radios).
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A nice simple antenna. Depending on your interests it could be worth checking where the swr dip is on 70cm. A 1/4 wave on 2m is 3/4 wave on 70cm which is also a low impedance length and a reasonable match to 50ohm. For a general purpose 70cm antenna could do a lot better. For me my 2m 1/4 wave also did what I wanted on 70cm which was close in uhf. On 70cm don't expect the performance of a dedicated 70cm antenna but it still may be useful.
That looks like a panel mount so-239 which is what I used for mine. On 2m I had it trimmed for 145.5MHz and there was a low enough swr dip at 439MHz which worked for me. An easy antenna to make and match.
That's not a bad idea, thanks for the tip. There isn't much activity on the 70cm repeaters in my area, but since I already have the antenna, it's worth hooking it back up to my meter.
And you're right, it's a panel mount SO-239. I trimmed this antenna for about 146MHz, so there should be a usable SWR dip on 70cm for mine as well.