I needed an antenna in the house for VHF and UHF operation, and I needed it cheap.Â So I decided to build one using five wire coat hangers, a single SO239 UHF panel mount connector, a 3/4″ PVC coupler, a small screw, and some scrap wood as a stand.
The SO239 connector set me back $1.38, the PVC coupler was from an old project (but they’re only $0.39 from our local big-box hardware store),Â I had the wire hangers in my closet and some scrap 2×4 was scrounged from the garage.Â Materials cost was a whopping $1.77 – call it maybe $2.50 if you include the cost of wood if you really want to stretch it.
My goal, get out and be heard on the local 2m and 70cm repeaters and be able to chat and check into the weekly nets from the comfort of my home office!
Here was my design:
To build the antenna, I needed a single vertical element and four ground radials.Â I hacked the coat hangers up and ended up with a single 19.25″ length from each of five coat hangers.Â I couldn’t get the entire length I needed out of the bottom of the hanger, so I had to straighten the wire where it bent to get it reasonably straight.
Next I took 4 of the wires and bent the very end – about 0.25″ – 0.3″ – toÂ about 120 degrees.Â These were put into the four SO239 screw holes for panel mounting the connector and a generous blob of solder was added to each.
Then I took the remaining length of wire and inserted it into the barrel where you would normally insert coax when assembling an antenna connection.Â Right in the top.Â A little solder and it was all wired together.Â I checked to make sure the radials wereÂ roughly at a 120 degree angle to the vertical.Â Close enough was good enough!
I took a few pieces of scrap wood and make a little stand about 8″ tall.Â This allowed me to hold the end of the antenna off the shelf and still connect the coax for the radio to it.Â I made the stand just tall enough so that when it was put on top of a shelf in my office, the tip of the antenna would be just an inch or so away from the ceiling.
I then drilled a hole in one side of a 3/4″ Schedule 40 PVC coupler.Â This was to let me run a screw through the other side of the PVC and into the wood stand.Â The PVC’s job is to hold the SO239 connector and let me screw the coax from the radio into it.Â Turns out that a panel mount UHF connector will fit really nice and Kentucky inside of a 3/4″ schedule 40 PVC coupler!
I fed my antenna coax up and wrapped it around the wooden stand a few times to act as a poor man’s choke. I don’t know how much it’s helping, I’m only feeding the antenna with a max of 25 watts, but it’s there.Â Then I pulled the PL239 end of the feed coax up through the PVC, screwed it into the SO239 connector, and settled it back down in the PVC.
That’s it, the antenna is complete!Â Total cost is maybe $2.50 plus about a hour of my time to put it all together.
Using this antenna, I’ve been able to get into all of the local repeaters I’ve tried using both a 4 watt Baofeng UV-5 Ras well as a 25 watt Radioddity QB25.Â I’ve checked into nets and just chatted with other folks on the repeaters with no problems at all.Â I’ve been told the antenna sounds fine.
I will readily admit this isn’t probably as nice as a commercially manufactured antenna.Â I don’t currently have a VHF/UHF SWR meter so I can’t tell exactly what the performance is.Â It was cheap, and the performance is good enough for the girls I go out with.Â It was definitely a fun little afternoon project and it gives me a workable dual band antenna to boot!