2 Meter VHF Quarter Wave Ground Plane Antenna – Ham Radio Q&A
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Are you looking for a fun and easy antenna project? Well the quarter-wave ground plane might be just the ticket so keep watching for more Hi, I’m Michael KB9VBR your host for ham-radio Q&A. I’m on a mission to inspire and educate the amateur radio community So if this is your first time here, please consider pressing that subscribe button Well, if you’re just starting out in amateur radio You may not have collected all of the resources that a more seasoned ham may have and this includes antennas when I first started in amateur radio my first Transceiver was a little handheld and it had sketchy transmit and on receive on all but maybe the closest repeaters. So To the rescue would be an external antenna Fortunately, there is an antenna that’s easy to build and quite inexpensive which is the minimum amount of parts That’s the simple quarter wave ground plain antenna for VHF So we’re gonna build a simple ground plane VHF 2 meter antenna ground plane antennas They’re pretty easy to recognize by their appearance. First off. You’re gonna notice the radiating element. This element is one quarter wavelength long or about 19 inches for the 2 meter band a next up will be the radios There’ll be three maybe four radios Going out horizontally maybe drooping at a 45 degree angle from the radiating element Each of those are going to be a quarter wave long eat also This particular ground plane that we’re going to build today is constructed on an SO-239 chassis connector so the radiator is attached right to the center pin of the SO-239 and the ground radials are going to come off the the base of the of the connector and then it and then attached to that will be a coax cable with a PL 259 connector running into your radio So to build this antenna first we’re going to need a couple calculations For the length of our radiator and our ground plane to do that. We’re going to use the formula of 234 divided by the frequency in Mhz To get the length of the radials and the and their main radiator So since I’m going to build this antenna Senate antenna Center it on the 2 meter band. I’m gonna divide 234 by 146 megahertz I’ll get 1.6 0 as my answer. That’s going to be the length of the radiator in feet so multiply that by 12 that’ll be The total answer for the radiator will be nineteen point two inches So my ground radials need to also be a quarter wave long. So I’ll use 19.2 inches also for their length With that said let’s assemble the parts and the tools. I have a length of 12 gauge solid copper wire Solid copper wire might not be the most durable, but it’s easy to find. Other things You can use maybe like our three thirty-seconds of an inch brass brazing rods copper coated steel steel wire or even a coat hangers, Those some of those up to Use whatever materials you can find that are handy next. I’ve got an SO-239 chassis connector You’ll find these at a ham fest, maybe an electronics store. You can order them online at Amazon I’ll put up with a link below in the video description below if you’re having trouble finding that SO-239 and then also you’re gonna need some electrical ring connectors some nuts and bolts to attach the radials to the base for tools I’m gonna be using the ISO tip butene iron since I’m outdoors wire cutters crimper pliers screwdrivers All of that kind of rounds out the tools for the list So to put this antenna together first measure out the elements using the formula You’ll need five. One for the radiator and four for the ground elements Next attach and crimp the ring connectors to the ends of four of the elements then solder the radiator to the center pin of the Esso 239 connector next Use the bolts to attach The radials to the connector. It’s a tight fit for these bolts to go into the into the SO-239 So I first pre tapped them with one of the one of the bolts to give it a little bit of thread and they went On quite easy. That’s all there is to it. Your antenna is now complete so Let’s check out this antenna. See how it Tunes up on the SWR meter Testing out the antenna add a Frequency of one hundred forty six megahertz, we’ve got an SWR of 1.1 to one and that’s with no adjustment just using our formula at all so if you don’t have a meter, this is a excellent antenna that you can build and be reasonably sure that if you follow the measurements correctly you are going to be in tune So to mount the antenna I saw a person using a length of PVC As a mast you can push the coax through the PVC if it’s if the P if the tubing is a 3/4 of an inch Or larger and then just let the antenna rest on top. It’s not the most sturdy type of mast, but it’s quick and easy So doing that we got the antenna up in the air. Let’s see how it transmits KB9VBR testing N9CLC KB9VBR. Good morning Wally. It’s Michael here down in Wausau Just Working on a little project this morning a quickie quarter wave VHF antenna, so we’re seeing how it hits the tomahawk repeater Yeah, well we only have it up a couple feet in the air so maybe if I get her up 10 feet or so, it’ll make a bigger difference, but Thanks a lot for the come back this morning and you have a great day. We’ll catch you later KB9VBR N9CLE Hope you found this project simple and quick to do This little ground plane will work great with your handheld radio or also a high-powered bass radio So don’t fear putting 50 watts or more of power into it. You can also make this antenna for other bands, too Maybe something for the six meter band the one point two five meter or 70 centimetres band All you got to use is your formula 2 34 divided by your frequency to find that Exact quarter wave frequency for the antenna For more amateur radio articles and information. Please check out my blog at www.jpole-antenna.com. If you like this video, don’t forget to hit the like button and also check out this other video that’s recommended right over there and subscribe to my channel to get notified when our new videos are really I’m Michael KB9VBR. Thanks for watching. Have a great day and 73

51 thoughts on “2 Meter VHF Quarter Wave Ground Plane Antenna – Ham Radio Q&A

  1. First antenna I built after I got my technician. Got it out of the ARRL Handbook. Not do sure you can get the SO-239 and other parts from Radio Shack.

  2. I built one of these a couple years ago, slightly different than your video only in that we had extra PVC parts so we could take the thing apart and store it in the PVC to transport. Otherwise, it looked the same and is a great antenna.

  3. Hi Michael. The first 2 meter base station antenna was that antenna, up in a pine tree. I followed the ARRL pamphlet I got as a new ham. I only had 2 ground radials and the instructions called for a loop in the wire ends, formed by wrapping the end around a broomstick. I still use that antenna.

  4. This great for beginners but as your build more antennas you one van improve design
    stainless steel radiator & ground planes.

  5. can i use copper from coax cable?the inisde of a coax cable used to hook up a satelite dish to the descrambler is sturdy

  6. Wow. Awesome SWR. No tuning either. Personally, I would like to see more videos like this. My favorite was the Leixen 10w Radio in a Ammo Can. Built one myself.

  7. Hi there.. I wanted to say that I'm a fan of your videos. I'm a fairly new ham and projects like these are just awesome. Thanks for taking time to produce these cool vids. I do have a question however, I currently have a vertical antenna for 2m and 70cm. I have it side mounded to my tower. My question is how far should it be? I have an swr of 1.3 on 146 mhz but on 446 mhz, it's an 1.8. What's your take on this?

  8. Awesome, as a new ham I will definitely be making this. I wish some store locally had SO-239 connectors. Wish Radio Shacks were still around. 73 – KM6VFM

  9. Thy these electrical connectors (link below). Remove the barrel from the plastic. Screw these to the SO-239 Chassis connector (5 barrels required). It is easy to remove your wires from these for transport (portable use, i.e. SOTA).
    https://www.amazon.com/uxcell-Position-Terminal-Blocks-Connectors/dp/B01MYCGMQO/ref=sr_1_14?s=industrial&ie=UTF8&qid=1534948690&sr=1-14&keywords=Screw+Terminal+connector+block
    You can also use these connectors for a 1/2 wave dipole. Don't remove the plastic though. Bend the wire at a right angle and insert into the connector. Then insert your stripped coax wires and orient wires vertically. Cheap, quick and portable.

  10. I like this project because it's cheap to build. New to the hobby. My two questions. If its outdoors what do you use to keep the rain out of the connector? What about lighting protection?

  11. Can a handheld type yagi antenna be made for 2meter frequency out of coper / aluminum, tubing or pipe? Something similar to the j-pole build. If so how do I figure the measurement for the frequency desired? Is there a formula to follow? Thanks!

  12. Hi Michael!! I just subscribed and
    I'm proud to say I'm subscriber
    number 8454!! I look forward to
    watching your videos and learning
    ALOT from you!! Thanks for
    posting and giving us all a chance
    to learn and do it right. Norman.

  13. Hi Michael!! I've got a topic for you:
    different materials for antenna
    building, ie: copper vs stainless steel vs aluminum;
    wood vs plastic vs pvc.
    Different conductive properties of
    each, strengths & weaknesses of
    each, etc. What do you think? Are
    radials, radiators & ground plane
    wires better in copper,
    stainless-steel or aluminum, and
    why. Also: can we mix them? I
    would love to see THAT video!!
    I'm sure you could produce a great
    video on all that!! At the beginning
    of the video don't forget to
    mention who the inspiration is
    behind that video!!😉. It might just
    inspire others to come up with
    other good ideas!! I can't wait to
    see it!!
    Keep on keeping on, brother!!
    73, Norman in Montreal.

  14. Nice vid, thanks, and greetings from the state below you. Does anyone know how you could adapt this to dual band, i.e. 2m and 70 cm? Would you just make it halfway in between the two?

  15. I'am curious if increasing the radiator wavelength e.i. 1/2, 3/4, 5/8 or possibly a full wavelength to the frequency would increase the gain of the antenna?
    Thanks for sharing!.

  16. Great vid! Question, I live in the Pacific Northwest and we get a lot of rain. I'm planning on making this antenna and was wondering about weatherproofing. Could I shoot a bunch of hot glue on the pl259 to keep water out? Will I get water inside the coax with a normal screw on connection? Thanks!

  17. Hi Michael, thank you for sharing what can only be described one of the easiest but useful little antennas inexperienced amateurs like myself can build. I have built a similar type of antenna for portable days out but I used a slightly different calculation which offered me a slightly longer radial (2948/Freq = length). I note that my swr is slightly higher than yours so maybe I stick with 234/Freq. Thank you for sharing. M6KVK

  18. I have made the 2m 70cm, my problem is I can’t get the solder to adhere to the copper wire and the so239 connector. So the main beam is the 2m, and then I attach the 70cm beam next to that. Can I move the 70 up a little bit to have its own connection to the 2m beam instead of having a big blob of solder at the 239. Like I said above need some direction to get the wire and solder to adhere to the 239 and be secure. Thanks Michael

  19. I have one of these in my attic, and it works really well. I added a 70 cm element to it and tuned the 70 cm operation using the SWR meter on my radio. I also have the MFJ antenna analyzer, but it does not work on the 70 cm band. I can reliably hit a repeater 25 miles away using 40 watts. It's supported by a truss to which I zip tied a short section of PVC pipe. Give it a try!

  20. Hi Michael
    I built the two meter quarter wave ground plane antenna ,I am measuring 2.7 SWR at 146 MHz .
    What would be a good SWR for this antenna ?any suggestions to make my SWR better ,my copper wire is cut at 19.2 inches .thanks in advance .

  21. Gonna try that for an FM transmitter. I did a dipole for it and it works but I wanna see if this will help any.

    And yeah I'll stay out of trouble lol

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