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If I would buy a ham radio with an outdoor antenna, what would I need to do to make it work (e.g can I just stick it outside) especially because I live in Miami and Miami doesn't exactly have the best weather?

Would putting an outdoor antenna require making an enclosure (including a roof)?

Marcus Müller
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hopefulhacker-Reinstate Monica
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    Welcome to the site, and hope your studies go well! BTW, while there's a [variety of origin stories](https://en.wikipedia.org/wiki/Etymology_of_ham_radio) to choose between, the general consensus is to **not** capitalize "HAM" as it's probably not an acronym. – natevw - AF7TB Apr 30 '20 at 20:49
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    @AF7TB Thanks! BTW I corrected the mistake. TYSM and 73! – hopefulhacker-Reinstate Monica Apr 30 '20 at 20:52
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    Given the number of questions that you have asked, I would recommend joining a local ham radio club and find an Elmer. They are are all good questions and are fine to ask here, but you will get faster and more simplified or complex answers as needed from a local person. Take the speaker wire example at 234/MHz feet, this value could be +-10% off of the proper length given the wires velocity factor and to a lesser extent its inherent inductance and capacitance and possibly non-uniform resistance. It is important to be able to measure the values. A local person could help. – KX4UQ May 01 '20 at 05:02
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    Joining a club is a great idea, but these are mostly very good questions, and give an opportunity to provide basic but critical mentoring, and most of these questions don't already have good answers here. – user10489 May 01 '20 at 05:57

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Antennas meant to be permanently installed are designed to withstand the elements. A proper installation would definitely not require an enclosure around the antenna. Pay attention to rated wind speeds when shopping around. There are even some antennas that are designed to withstand hurricane-force winds. For a permanent installation, you'll also need to carefully consider grounding and lightning protection, especially in an area prone to frequent thunderstorms.

I saw in some of your other questions that you are on a tight budget. With that in mind, it might be a better idea to buy, or even build, a cheaper antenna that you can put outside when you plan to operate. You can make a simple wire dipole with only speaker wire, and connect it to your radio with a binding post adapter. This way, you wouldn't have to pay a premium for a robust antenna system, since you would keep it indoors most of the time.

Nat Mote
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  • Thanks a lot. Just by the way. Could you recommend any videos on how someone could go around making a wire dipole ("I'm a total and complete noob)? Maybe a youtube video? – hopefulhacker-Reinstate Monica Apr 30 '20 at 20:38
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    Hate to complicate things, but since you mentioned "proper" [/permanent] installation, grounding is very important too — especially in a place with thunderstorms! – natevw - AF7TB Apr 30 '20 at 20:43
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    Making a wire dipole sounds intimidating but it's actually very simple! You compute the length in feet of each of the two segments of the dipole by taking 234/(frequency in MHz). Then you cut two segments of that length (speaker wire makes this easy since it's two wires stuck together), and you're done! Then just attach it to a binding post adapter, like this one https://elecraft.com/collections/test-equipment_accessories/products/bnc-bp – Nat Mote Apr 30 '20 at 20:46
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    You can also use it as a monopole, where you hoist the hot wire (red) and run the ground wire (black) along the ground. – Nat Mote Apr 30 '20 at 20:47
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    @natevw-AF7TB Good point, I've edited my answer to mention grounding, too. – Nat Mote Apr 30 '20 at 20:49
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    Don't forget about the trusty J-Pole for VHF or UHF. Simple cheap, kind of hard to ground properly, the proper point is at the shield connection of the coax. The bottom of the "U" is not neutral and must be isolated from the ground and mast. Tuning... – KX4UQ May 01 '20 at 04:12
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    All antennas require tuning. If you connect a mismatched antenna to a transmitter, you risk destroying components in the transmitter. Modern HF transmitters are more forgiving (at low power levels, QRP) and can accept up to a 3:1 mismatch. The Boefang that was recommended in a previous post, cannot handle more than a 1.5:1 mismatch. If you are considering the Boefang, buy a cheap 1/4 wave mag mount for a car($9-15), and place it on a 18 inch metal plate or other conductive surface. – KX4UQ May 01 '20 at 04:33
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    It's already in your answer, but I can't stress it enough. If you have an outside antenna in Florida, eventually you will get a direct strike on it. Good grounding and surge protection *outside* the house is critical. An air balun (5-6 turns of coax bundled in a tight loop) is an important part of this. – user10489 May 01 '20 at 06:00
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If you are doing VHF and UHF a simple antenna like a J pole can easily be made or if your prefer purchased. I have also liked making my own antennas. For HF frequencies a dipole is also easily made form wire. I made a end feed half wave that also require winding a toroid to make the matching transformer, but that is not difficult to do.

All antennas will be affected by weather and you should check them periodically looking for corroded connections and other issues. Most HAMS will get years out of their antennas. I try to use an antenna analyzer about once a month.

You should protect all connections from the weather. I wrap my coax connections in self sealing tape to prevent water form getting into them.

Also be careful with home owners associations. their bylaws usually prohibit antennas, thought often simple wire antennas are not visible and don't get noticed.

Jim
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