Need to make a cheap antenna

[Josh380]

Ok. So I need to find a way to make a cheap (free would be better) antenna for my BFUV5R+. Let's not get into type acceptance for gmrs and all that biz. I have zero budget, so if there is a way to make one from basic household stuff, please let me know. I want this to be for home use. I know there are better solutions radio wise for home use, but this is what I have to work with, with the budget I'm on. I should also mention that mounting anything to the roof is not an option, so my options are limited.

I bought one of those cheap mag-mount antennas for it and honestly, the rubber duck antenna does better. And, yes, I did mount the antenna to a surface with a suitable ground plane.

Any ideas would be most appreciated! I'm even willing to hack the coax from this POS antenna..I think the coax and connector are worth more than the antenna. Those SMA connectors are expensive.....

 

[fmink]

GRE but that does not matter as it will not down load STATE or COUNTY. It states that there is an error and it will not Load any state or county. It will let you enter United States and that is where it stops.

 

[wyShack]

I don't know what you have available for materials, however if you are just interested in GMRS, you may search for amateur radio antennas for the 70 cm band-there are lots of home brew antenna plans on the internet. most have the formulas for calculating the dimensions and the simple ones are broad banded enough that you can likely do OK. do it yourself antenna building can be an addicting hobby but is easy to get into.

73

 

[iMONITOR]

What are you hoping to accomplish? You can put lipstick on a BFUV5R+, but it's still a BFUV5R+.

 

[Josh380]

Would a simple dipole antenna do the trick? I understand it would have to be cut to a certain length..and am unsure if coax length plays into the equation.

 

[R8000]

You could Google search or even YouTube search for ideas for building antennas.

 

[teufler]

A dipole would work, it wqould have to be nounted vertical instead of horizintal, for optimum reception. A wire, pretty much longer than 50" or so, would give better reception than the scanner 's rubber duck. The normal scanner's antenna is convienent to carry and it will work across the spectrum. Are you using Arc 500 software? Now there are two different subject being discussed,. For Josh380, with out some antenna adapters, making an antenna that will fit the uv-5, installing an sma connector will be hard. Plus they are a sma female instead of a sma male. I found an adapter that fits the uv5 radios, that converts to an so-238. This opens you up to add kinds of antenna designs. A tape measure beam antenna works very good on the vhf band. In lab tests, coax length does come into play, but most just hook up what length they need. Coax quality, rg-8x for 50 feet or less, rg213 or lmr 400 would be best over 50 feet. The later will cost $80.00 or more for 100 feet at least. Tape measure beam, about $9.00. Now Fmink, what softare program are you using. Arc 500 ?

 

[Josh380]

I was the one that asked about a dipole. Geez..lol. I feel like I'm back on CB fighting over a channel.

I have the coax with the sma-f connector attached from my cheapo mag-mount antenna. So googleing tape measure antenna brings up results for a yagi antenna. Since I don't have a spare tape measure to hack up, or pvc pipe, I'm basically scavenging for parts. Options?

 

[mmckenna]

Make a basic 1/4 wave ground plane antenna. You can fabricate this from a wire coat hanger. Just google home built 1/4 wave antenna....
1/4 wave antennas are broad banded enough that you don't need to worry too much about tuning. Getting the measurements close will do the trick.
Getting the antenna up high will improve performance.

 

[Josh380]

Thank you mmckenna. Found a calculator online. About 6" all around. You've narrowed down several hours worth of google searching with one, straightforward answer.

 

[iMONITOR]

A ground plane design will have no gain. If you're mounting it high, with a long run of coax, you need some gain on the antenna.

 

[teufler]

I believe you didn't want to mount an antenna on the roof, so getting a ceap tape at the hardware out outlet store . The antenna that you can make is noT real expensive in parts. They will exhibit a gain of ABOUT 7DBD, AND DIRECTIONAL. i USE ONE HERE IN THE HOUSE, AND AT 9 FT ON THE FIRST FLOOR, i CAN NOTICE A DIFFERENCE

 

[mmckenna]

A ground plane design will have no gain. If you're mounting it high, with a long run of coax, you need some gain on the antenna.

Right, a quarter wave antenna is considered "unity" gain. Gain antennas can help overcome feed line losses, but it comes at the effect of radiation patterns. High gain antennas are not always the best choice and the traditionally have less bandwidth. Less bandwidth translates into needing to get the resonate frequency of the antenna closer to exact. Not always the best choice for someone with limited funds and resources and building their first antenna.
Using a high quality feed line helps, too.
But I suspect that isn't the issue here. I think the OP was looking for a basic antenna to provide some improvement over the stock flexible antenna. That isn't hard to do, most portable radio antennas can be measured in -negative- gain.

Higher gain antennas are not as easy to make, matching, coils, etc. all take some experience and some test equipment that the OP probably doesn't have. A quarter wave is a good place to start. Getting this one built will provide some experience and confidence. Next project can be to build a gain antenna and procure some better coax.

 

[Josh380]

Mmckenna is right, I don't have an SWR meter. I'm not a complete novice. I made a simple dipole antenna for my CB out of speaker wire that worked alright.

Ok. So main points here. Cheap. No Tuning. Not roof mounted (this is not optional, I rent and cannot put an antenna up). What's my best option?

 

[teufler]

WELL THAT IS WHY THE ANTENNA IS CALLED A TAPE MEASURE BEAM, THOUGH i ONCE tried a beam out of a piece of wood and coat hangers straighted out. Didn't do to good. PVC from Home Depo is less than $10.00 for a 12 ft piece so several antennas can be made from one piece. Got a tape measure from Harbor Frieght for $2.00 for a 25 ft tape. Again 1 tape makes several antennas. The antennas are very portable, good for a camping or fishing trip. You couled also put a jpole together, the pvc is not the radiating part but for support. You can also use tv twin lead, for a jpole. Then the tv twin lead can be tacked to the wall. I also have a antenna made from 50 ohm coax, that has the outer jacked removed just exposing the center conductor. 18 inches is an 18 inch quaurter wave antenna. I just stich the antenna with tape to the window. All of these ideas are verfy cheap, they work,

 

[mmckenna]

Good point, forgot about the J-poles. Easy to build out of some old TV twin lead, provides a bit more gain.

I built a 6 meter dipole once out of some 1/2" copper pipe. Worked well enough. Was able to make some 200+ mile contacts with about 10 watts.

 

[linboogy]

Here is the one you may want to consider for low budget
Watch the SWR though

 

[Josh380]

Lol. Yeah might be a little tricky to get that one right. I hope nobody is stupid enough to try that.

 

[mrweather]

Looks like a variation on the 1/2 wave folded dipole (which do work well). Not sure about this design though!

 

[popnokick]

Flower pot antennas are simple, omnidirectional gain antennas that are relatively inexpensive to make. This website offers several variations -
Dual Band Half-Wave Flower Pot Antenna – VK2ZOI