Handheld Radio with External Antenna from Home Question

steviedeviant

steviedeviant

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StevieD
I recently moved into a home that is closer to the airport and thought I would try to see if my handheld would pick up better. I found I was actually getting some decent sound though not great. Then I started thinking about connecting an external antenna. The home already has an external antenna that is in the attic for TV with coax coming down. I get excellent reception of all local channels. Why not do the same thing for the handheld.

So, my question is this: Can someone point me in the right direction on what I might need to put an antenna in the attic and then drop a coax down with some type of adaptor that could connect to my transceiver? I am not exactly sure to purchase.
 
Had the same crazy idea but was leaning towards purchasing a base transceiver. Following
 
steviedeviant said:
I recently moved into a home that is closer to the airport and thought I would try to see if my handheld would pick up better. I found I was actually getting some decent sound though not great. Then I started thinking about connecting an external antenna. The home already has an external antenna that is in the attic for TV with coax coming down. I get excellent reception of all local channels. Why not do the same thing for the handheld.

So, my question is this: Can someone point me in the right direction on what I might need to put an antenna in the attic and then drop a coax down with some type of adaptor that could connect to my transceiver? I am not exactly sure to purchase.
Click to expand...
I am a old cb ham radio enthusiast. Used to have antennas on my roof, took them all down years ago when I got a new roof and never put them back up to the relief of my neighbors. lol
I am not sure about a compact antenna for the attic? Pretty sure I see this one outside the small FBO at my airport. Back in the day Radio Shack was my go to for antennas.
https://www.aircraftspruce.com/catalog/avpages/av5_ant.php
 
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First go up into the attic with the handheld and see if you get good reception there; if not, no point putting an antenna there. Next, get some RG-58 coax (not the same as what's used for TVs) with BNC connector ends and a female-female BNC adapter and connect it between the radio and the original radio's antenna. With the original rubber duck antenna you usually don't need a ground plane. Use it that way (it's the setup I had on my Kolb) or, if you want to keep the original radio antenna accessible, buy or build an antenna. There's a lot of information online about simple homemade antennas.
 
For listening, the antenna is not that critical. For transmitting more so.

A J-pole (2M dimensions work fine, but you can fine tune to aircraft band easily).

The other one I like is what we called a Virus Antenna. You use an SO-239 panel coax connector and 4 pieces of wire (coat hanger or welding rod). About 18 - 19" inches from memory for 144- 148MHz. Solder one rod to the center pin, one each to the corner holes. Bend the rods in the corner holes away from the center rod at about a 45 degree down angle.

J-Pole info - https://www.dxzone.com/catalog/Antennas/Slim_Jim/

virus info - http://ccarc.org/_misc/so-239_ant.html

The last one has slightly different dimensions for the center and corner wires. I always made the same same and they worked great.
 
Pinecone said:
For listening, the antenna is not that critical. For transmitting more so.

A J-pole (2M dimensions work fine, but you can fine tune to aircraft band easily).

The other one I like is what we called a Virus Antenna. You use an SO-239 panel coax connector and 4 pieces of wire (coat hanger or welding rod). About 18 - 19" inches from memory for 144- 148MHz. Solder one rod to the center pin, one each to the corner holes. Bend the rods in the corner holes away from the center rod at about a 45 degree down angle.

J-Pole info - https://www.dxzone.com/catalog/Antennas/Slim_Jim/

virus info - http://ccarc.org/_misc/so-239_ant.html

The last one has slightly different dimensions for the center and corner wires. I always made the same same and they worked great.
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That’s a great antenna used by almost every Ham operator around the world. Sooopersimple. For best results at the 120-130Mhz band simply change the dimensions to 22”. Since you’re cutting wire hangars why not use the more technically correct number?

Not that it matters too much for listening but, this is POA, and the pencil is often sharpened as we go.
 
Jim Weir published a Kitplanes article with a J-atnenna years ago, 1/2" copper pipe, a few connectors and a BNC that works very well too. Surprised no one has mentioned that idea.
 
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skyking3286 said:
Jim Weir published a Kitplanes article with a J-atnenna years ago, 1/2" copper pipe, a few connectors and a BNC that works very well too. Surprised no one has mentioned that idea.
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Jim Weir also published the dimensions and directions for making an air band antenna with copper foil tape that is supposed to be very good - it will require a ground plane of some (any) sort.
 
There is nothing as good as a ground plane antenna mounted on a mast atop the roof. The antenna should be cut by a pro to the proper fraction of the optimum wave length. In the 1969-79 time-frame I lived near the foothills of the LA basin. I could hear LA County Sheriff units 40 miles away. Near an airport, a handheld should be awesome with an external ground plane antenna.

You can't legally transmit, though. ;)
 
J-pole antennas are great, but they can be a little finicky to build/tune if you're not used to it. If you just want something you can buy off the shelf, a discone scanner antenna will work. They are available for $100 or less. Make sure you get one that goes down to the air band, just above 100 MHz. It won't work quite as well as a jpole or a ground plane, but better than the little rubber antenna on the radio. Agree that it might not work at all inside the attic. 50 ohm coax is best, but for receive only you can also use RG-6 75 ohm tv coax, and it'll probably be lower loss. Keep the length as reasonably short as possible...with RG-58 if you have to go much past 100' you might not have much advantage over the little antenna on the radio.
 
Do you have some TV coax laying around the house anywhere? You probably do. And an available TV Jack that is connected to the TV antenna you already have? If so, then by far the easiest solution is to just try using what you have. Buy one of these:

https://www.amazon.com/Connector-2-...t=&hvlocphy=9026243&hvtargid=pla-872702290030

Connect it to your handheld and to the TV coax to the wall/TV antenna, and see how it works. Might work great, might not, but it’s only a few bucks to find out.

Yes, purists will speak of the impedance mismatch, SWRs, cable loss, horizontal vs vertical polarization, etc. But we’re talking receiving here, not transmitting, so this solution might just be good enough. And it’s cheap!

Oh, and don’t accidentally hit the transmit button. That could damage your TVs.
 
skyking3286 said:
Jim Weir published a Kitplanes article with a J-atnenna years ago, 1/2" copper pipe, a few connectors and a BNC that works very well too. Surprised no one has mentioned that idea.
Click to expand...

Several people have suggested J-pole antennas.
 
aterpster said:
There is nothing as good as a ground plane antenna mounted on a mast atop the roof. The antenna should be cut by a pro to the proper fraction of the optimum wave length. In the 1969-79 time-frame I lived near the foothills of the LA basin. I could hear LA County Sheriff units 40 miles away. Near an airport, a handheld should be awesome with an external ground plane antenna.

You can't legally transmit, though. ;)
Click to expand...

Really? So my two 10 foot dual band verticals (6.5 dBi Gain on 2m) and 2M and 440 MHz 11 element phased yagis (13 dBi gain) do not perform that well???????

BTW, the "virus" antenna mentioned IS a ground plane antenna. I have worked a 2M repeater, from a hand held, 35 miles away with on the "virus" antenna. And only at about 6 feet high, not on the roof.
 
Pinecone said:
Several people have suggested J-pole antennas.
Click to expand...
The performance of the j-pole and a ground plane should be the same. The differences are: the j-pole (½ wavelength) is twice the length of the ground plane (¼ wave length) so mounting space might be an issue. The j-pole can be directly connected to ground, the ground plane needs to have the center vertical isolated from ground. Probably not an issue in an attic.
The "virus" ground plane is likely the easiest to build. For receiving the dimensions are not that critical - you aren't trying to capture the weakest possible signal from the furthest station.
 
OKDonn said:
For receiving the dimensions are not that critical - you aren't trying to capture the weakest possible signal from the furthest station.
Click to expand...

Resonance has nothing to do with reception. You could also take the stubby antenna off and stick random piece of wire longer than the current antenna and receive better.

Just don't key the transmitter.

Most short wave listeners use long wire antennas, not resonant ones
 
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