Indoor Antenna Projects 1

Indoor Antenna Projects 1

Indoor Antenna Projects 1: Practical indoor antennas for everybody

HF Indoor Antennas:

Some practical indoor antennas that can be built by anyone:

** HF foil antennas

** VHF/UHF discones

** Wire beams

** Attic VHF/UHF rotables

** Tape antennas

** Telescoping VHF/UHF indoor beams.

HF Foil Antennas

HF foil antennas are too weak in their physical construction for outside use. Foil antennas are just what the title implies, foil. They are made from ordinary aluminum foil, the kind used for heavy duty cooking, such as roasting a turkey.

This antenna goes in the attic of your home or condo. Apartment dwellers may have a time with this antenna depending on their location within their complex.
Materials needed are two to three rolls of aluminum foil, copper tape with electrically conductive glue, a staple gun and staples, and coax with connector.
By stapling the foil in a loop or dipole configuration on the attic rafters, a simple antenna can be formed.

===================== ======================= || balun if desired | | | coax to shack

========================================== | | | | | | | | | | | | ==================== ===================== || Balun if desired | | coax to shack

These two configurations are excellent when used with a tuner for the various bands on amateur radio and SWL listening. They are cheap to install and can be made into other configurations, by the amateur, if desired. A relay can be installed to provide dual antenna configurations if needed. With this device you can switch between a dipole and the loop for different propagation conditions. Size and shape is dependent on the attic structure.

Connections from the foil to the coax or BALUN are via the copper tape. There are copper tapes available on the market that are used for EMI applications. These tapes are expensive so if you can get a piece of some of that tape from a buddy, it will work wonders for you.

Otherwise, there is a trick with regular copper tape and the aluminum foil that you can do. It’s a simple folding technique that insures a good connection and yet requires no soldering except for the coax/BALUN connection.

Practical indoor antennas for everybody


====================================== Aluminum |——————————|| foil | =============================== |————————————– Copper tape

This folding method insures good contact on more than one surface. One warning, do not leave air gaps, as it will have a capacitive effect.
Solder doesn’t stick to Aluminum foil very well. With enough heat, you can solder anything. Too bad the aluminum foil won’t hold up at that temperature and neither will the solder.

You now can solder leads to the BALUN or solder the coax direct to the copper tape.

For an indoor antenna, the foil antenna works rather well. It can out perform a vertical and pull in the weak ones with ease. I think you’ll find it one of the most inexpensive antennas you can build yourself.



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Fence Antenna Ideas

Fence Antenna Ideas list, Jan. 1999

John Matz: This reminds me of my yard about ten years ago. You have a wooden fence. Good.

One suggestion:

Get a good antenna tuner (if you don’t have one) and learn how to use it.

2. Get some insulated wire (house wire will work) and an eight-foot ground rod.

3. Put the ground rod in near the fence. That’s your coax ground.

4. Put a number of 1/4 wave radiators (234/f in feet), separated, up on the fence … like 8′ for 10m, 16′ for 20m, etc., all in parallel to the coax center conductor. They don’t have to be straight … just 6 feet up, and then over horizontally … or slanted at a 45 or so, and then bent over. Keep as much of the wire as high as possible.

If they can be placed far from the house, then you can put up at least three radiators for three bands easily.

Use the tuner inside the shack.

I’ve used this method on 75m too. It’s not as efficient as some antenna systems, but it is cheap.

You can use wire sizes such as 14 gauge wire for your fence antenna and no one will be the wiser when it comes to detecting your antenna.

These types of stealth antennas are great for the survivalist needs in radio communications because they are small, lightweight and portable. Multiple bands of these stealth antennas can be wound up on a spool and thrown into your bugout bag or your go box.

A survivalist new to radio communications may come into contact with certain radio and antenna “experts” who will say these fence antennas (or any stealth antenna) are “marginal”. The design of stealth antennas is that they are difficult, or even impossible, to detect. Its a given that they may not perform as well as a commercial antenna mounted high up on a tower or pole. But try to imagine dragging these aluminum antennas around with you as you try to set up a survivalist camp. You’d likely abandon the thing after you put it up the first time.

But stealth antennas such as this fence antenna can be placed against a fence or any other small structure in the yard of your home.

fence antenna

Stealth Hidden Camouflage

Stealth Hidden Camouflage

Stealth: stealthy – furtive or surreptitiously, denoted or otherwise marked by quiet, caution, and secrecy, it can also mean to take great pains to avoid being observed;

Stealth is an absolute necessity when you are in survival mode especially when it comes to your communications equipment. The very best communications antenna for a survivalist is one that no one can see. You know yourself that paranoia will run rampant and anything seen as a “threat” will be reported. The last thing you want to do is to draw attention to yourself or your location by having a huge antenna sticking up in the air. Sure, the big antennas work so much better but they also tend to attract unwanted attention. So with this page we will show you some antennas that will perform very well for the bands they are created for and yet will not draw a lot of attention.

Before you go any further on this page you may want to read about a ham operator who specializes in working stealth modes with stealth antennas. The article is entitled: “Secrets of a Successful Stealth Operator“.

Stealth Antennas

The Grasswire

Grass Wire Antenna
Grass Wire Antenna

What is it? Put simply, it is an end-fed, longwire antenna that is laid right on the grass. Hence the name. The original grasswire used by K3MT in the summer of 1988 was just 204′ of #18 AWG magnet wire laid along the property line, anywhere from 1″ to 6″ above the ground. This sketch shows plan and elevation views of a typical installation. Both an 8′ ground rod and optional counterpoise wires are shown. Use one or the other. Both are not needed. (Click the image for a better view of the Grasswire Antenna.)

Small Loop Antennas

Magnetic loops are very effective small antennas. these 3 to 3 1/2+ foot antennas perform close to and in some cases (low mounting heights for one) better than even a small beam. The reason is that a magnetic field is much more concentrated than an electrical one, for example a small horizontal loop at 17 feet performs better (lower radiation angle) than a full size dipole at 35 feet, in fact better for DX than a beam at that height because of the much lower takeoff angle. If you place a beam 1 foot off the ground it will only radiate straight up while a vertical loop will still work DX stations quite well. This smaller more intense magnetic field also has the advantage of greatly reducing TVI – RFI potential if the loop is more than 15 feet or so away from TV antennas, electronics etc. Another advantage of this magnetic field is the very low background noise heard on the loop because most man made noise is electrical fields. For example if you lived next to a Shopping Mall the loop would not hear all that lighting and power transformers. Also reducing interference is the loops “Hi Q” which means that it receives & transmits on a narrow band range compared to the “full size” antennas. This effect is very pronounced on the lower bands that the loop will work.

Low Profile Operating Outside Antennas

Antennas outside ? Not here ! Well you might be surprised. There are many methods to get your antennas out in the free air. The key here is do the very best you can to blend in or conceal your installation. Do your best not to attract attention. Install your antenna at night if possible, another way is to mix it in with some other project like painting, repairs or hanging Christmas lights.


A little paint does very little to your RF efficiency but goes a long way to disguise your antennas. Since my house is in the clear with few trees I use a blue-gray color that blends into the sky and in my case my house. Use a flat color if possible. Also there is a line of camouflage paints that are made for cars that are great around foliage, fences or decks. Experiment by painting boards to see what will work best for you.


Radials: On HF the length of the radials on the ground is is not as critical because the earth detunes them. Run as many as you can as close as you can to the 1/4 wave length for your lowest frequency. I would suggest that you bury them down about 1 inch. Radiator(s): On VHF & UHF full size and radiators are usually fairly easy to hide. For example use 3/16 rod instead of 1/2″ tubing for your J-pole and paint to match, or hide it in a fake roof vent. Several amateurs have built 1/4 and even 5/8 wave antennas into a working wind vane. On HF verticals can be built into “birdhouses” on a pole, these can be full sized on 10 meters or so and loaded or capacitance hats in the “house” itself for other bands. A popular theme is the flagpole antenna. One design for a multi-band version is in the ARRL antenna book, it consists of a pole made of PVC with home made traps inside. Another good way is to feed a ground isolated 26 foot pole against a radial system with a concealed remote turner at its base. Also a wire radial can be run up a wood flag pole. Coax: Use a good quality coax cable to reduce RF & interaction problems.


Dipoles can be very effective and also being balanced usually are some of the cleanest in terms of TVI and RFI. The eves of your house is a good spot to hide a dipole, just staple it up there and paint to match. Also a dipole laid flat on your roof can have good results. Inverted Vee configurations tend to work best to stateside contacts while flat tops high in the air work best for DX. A surprisingly good choice is the “invisible wire”, small gauge wire as small as 30 gauge can be used if suspended properly, I suggest 26 gauge magnet wire. These small wire sizes will create some loss but not too much until you get to the low bands and even there will work OK. Also 18 gauge or so wire can be used and allowed to oxidize to have no reflection of sunlight. Caution with colors is necessary to prevent birds from running into your wire. I found light green is invisible to our feathered friends but they avoid dark green. These antennas can be supported by trees, fences etc. Fishing line is very useful for tying to structures and pulleys with small springs or weights can be used to let the dipole move in the wind without stretching. Feed line: A little care is needed here, be careful of running parallel to electrical lines or duct work if using balanced lines. Use the best coax or twin lead you can but if you can use 300 ohm TV lead with some loss for easy routing.


This is a bit tougher, VHF & UHF beams can be hidden from view behind chimneys or trees. HF beams even on 10m are big and hard to camouflage but a clever ham could possibly shorten one to look like a TV antenna. I expect to see more antennas like the new Hy-Gain 2/6 meter beam that looks a lot like a TV yagi and lets you take advantage of the Communication act of 1996. This FCC ruling states that if you own your property you can have a outdoor TV antenna despite local covenants etc.

Commercial Antennas For Stealth Mode

portable vertical antenna
BuddiPole – It’s a dipole… It’s a vertical… It fits in your travel bag! The Buddipole™ is more than an antenna, it’s a versatile system for launching your signal. Optimized for transmit power and proven for DX work, the Buddipole™ is the secret weapon used by HF portable operators all around the world. Precision engineered for maximum performance using ultra light composite materials and High-Q coils. Zero-loss balun with Quick-Connect feedpoint.

The CliffDweller II antenna!

The Original Variable Length HF Antenna

The CliffDweller II is the Original variable length HF antenna that adjusts it’s size to fit YOUR operating environment. 6 to 80 Mtrs. – QRP to 100 Watts – Anywhere you need it.
Composed of 130 feet of wire (a full half wavelength on 80 mtrs!), the CliffDweller II operates in as little as 16 feet (8 feet per side) to a fully extended length of 50 feet (25 feet per side) or anywhere in between. It works in any space you have available!

For traveling or for storage, fully compressed (as shown), the CliffDweller II takes up less than one foot of space. Take it with you anywhere you’ll need an HF antenna. Operates great in permanent or portable operation. Makes a great emergency “have on hand” antenna – used by several emergency ham services around the country.

The Force 12 flagpole antenna is a large diameter aluminum pole that is the actual antenna. It is not a plastic tube with a wire inside. The Force 12 flagpole is an effective antenna and is a solution for many people who live in restricted areas, while allowing us to be patriotic. The basic flagpole antenna system is composed of the flagpole, the radials and the feed line. The optional feed point kit contains a feed point pigtail that connects the flagpole to the coax feed line and four (4) radials.

One of the best choices in stealth antennas is those produced by the Zero Five antenna company. Their antennas are quite hard to discern and can be made even more stealthy by applying a coat of paint that coincides with the surrounding areas. Zero Five also sells flagpole antennas that are virtually impossible to discern with Old Glory displayed on them. We have a little more detail on the Zero Five antennas on this link: Zero Five Antennas.

Grasswire Antenna © MICHAEL TOIA, K3MT .

Small Loop Antennas © CLIFFORD HOLLOWAY, N0HC

Low Profile Operating Outside Antennas © CLIFFORD HOLLOWAY, N0HC

A Successful Stealth Operator

A Successful Stealth Operator

Stealth is a more a lifestyle than a word but we have used on other pages of this same web site and some may still wonder what to do about stealth radio stations and how to do it. Set them up, that is. This article from a well-known amateur radio operator who has actively pursued the radio waves while keeping his presence unknown has been adapted to our site in such as way as to keep search engines from labeling it as duplicate content.

“Secrets” of a Successful Stealth Operator

This person, whose name and call sign will remain anonymous, lives in a neighborhood governed by the usual plethora of antenna restrictions, homeowner covenants, and of course the HOA Nazis who deem it their mission in life to see how miserable they can make life for others in the neighborhood. I have been quite successful and quite active in amateur radio despite the HOA obstacles.  I participate in a great many of radio contests, and I enjoy plenty of DX1, using both QRO2 and QRP3 powered operations. In the next few paragraphs I will try to explain some issues that I have dealt with concerning stealth radio operations.


A good many of the amateur radio operators I have came across have mistakenly made the assumption that the only way an amateur radio operator can ever work any DX1, participate in any contests, or earn WAS or DXCC4 is with huge beam antennas, full-gallon5 linear amplifiers, and tall towers. Now,there’s no doubt in my own mind that those items will give them the needed edge in communications and please understand that I do not suggest that any of my antennas are more efficient, stronger, or better in any way than another operator who uses a good beam antenna on a tall tower. And yet, even though I have neither of the latter two items I have managed to become a successful contester, QRP3 aficionado, DX1 hound, ragchewer, and any other type of operator. And I did this all through the use of well-designed, simple wire antennas and a vertical antenna. And added plus for me is that I get a particular amount of joy when I beat out the so-called “big gun” stations in a DX1 pile-up.


A great deal of the time it is your only way to enjoy your amateur radio hobby. Then some operators run stealthy radio setups just because it helps to keep the peace. It has always struck me as funny how your neighbours (all of them) are very peaceful, laid back, and even supportive of your hobby up until you put up your dream tower with a beam antenna on top of it and low-band dipoles hanging off the sides of it. As Gomer Pyle used to say, “Shazaam!” You are now able to work some really great DX1 and don’t forget that you also get the additional side benefit of your antenna system’s magnetic properties. Why is it magnetic? Your high-performance beam, tower, and all the associated dipoles hanging down form it is bound to draw complaints from everyone within your immediate neighbourhood extending out to miles beyond where your antenna is at. The next thing you know you will find yourself accused of everything from TVI6 to sterility of the neighborhood pets, even though you and the family have been on vacation on another continent for the last month with the power to the house shut off. So the answer to the question of why run in stealth mode is this: IF THEY CAN’T SEE YOUR ANTENNA THEN THEY CAN’T COMPLAIN ABOUT IT. Don’t get depressed if the first stealth antenna you try out doesn’t work out for your because you’ll need to experiment with several types of stealth antennas to find one that works best for your particular location but believe me, it works!


Should you discover that you live in a neighbourhood, a town, or even city that the same types of restrictions on the books then y0u will need seek out some opportunities such as some of the following:

  • -Is there attic in your house, condo, apartment (unlikely in some trailers used in senior retirement communities)? As long as you have access to the attic you will soon discover that you will be able to hang many different types of antennas in it. I myself have been able to find enough space for loop antennas as well as dipoles in several ham radio operator’s homes who I have helped get on the air in stealth mode.
  • -Were you blessed with one or more trees when you bought the new house?  Both front and back yard trees allow you many opportunities to erect resonant dipoles and even multi-band vertical antennas. Common sense will tell us that the more trees you have on your property the easier it will be to hide more and bigger antennas hanging from them.
  • -Be sure to read all deed restrictions, or HOA covenants closely, hire a real estate attorney to be sure nothing is hidden from your untrained eye. There are very few communities that restrict flags that are securely attached to flag-poles or even bird houses for that matter. You can easily hide a multi-band vertical antenna inside either a flag pole or a bird house support pole. Keep in mind when explaining that bird house up on a 30 foot pole is because birdhouses purple martins really should be mounted up as high as is practical to attract the birds. As long as you get to mount either of these poles you will then be able mount guy wires to keep your flag pole or bird house up. Instead of guy wires you can use the ‘guy wires’ as stealth inverted-vee dipoles and single or multi-band sloper antennas!
  • -The underside of the roof of your house is called the eaves and you can easily hide a loop antenna underneath these eaves. Attaching the antenna to the house can be accomplished small insulated standoffs all the way around your house. You will then run the feed line into the house through a soffit vent and into your operating area. Should you find yourself living in a duplex or other multi-family home without any way to get a loop up then there are other alternatives? All you need to do is hide resonant dipoles up under the eaves on whatever sides of the home that you have available for your use. If you are able to put up two dipoles mounted at 90 degrees angles to each other then you’ll soon discover that you be able to work almost all of the USA with relative ease.
  • -Maybe you don’t have trees but you do you have a good size backyard with a wood fence around it. This type of fence can easily hide a very low mounted loop, dipole, or doublet antenna without ever being seen by the neighbours. Even though these particular antennas exhibit a near vertical take off angle they should work just fine for normal contacts within several hundred miles or more from the operator’s QTH, possibly even some close by DX.

Always use your imagination!

Every house, home, trailer, condo, or apartment has its own particular OPPORTUNITIES available to you. You just have to be on the look-out for them, and then once you find them you must ACT. Through the years I have been able to see antennas laid on the grass of the back or front yards, metal (chain-link) fences can be loaded with an antenna tuner, small gauge wire that surrounds the shape of the house and then painted the same color as the house to make it nearly invisible to prying eye. All of these are different approaches to a common communications problem but had similar results in that the ham living at that particular location was actually ON THE AIR, and making radio contacts!



Paraphrased for use with search engines while maintaining author’s intent and copyrighted information.

1 DX: Literally “Distance”. A code from the earliest days of radio meaning a far away signal.

2 QRO: High power, in some circles anything over 100 watts is considered to be high power.

3 QRP: Low power, generally QRP is 5 watts and less. Some operators use milliwatt transmitters while attempting to work long distances with the least amount of power.

4 WAS DXCC: The letters stand for Worked All States which is an award given out by many amateur radio organizations for working all 50 American states on a particular band or mode. The letters DXCC signify that a station has communicated with at least 100 DX country entities

5 full-gallon: A legal-limit amplifier of 2000 watts. Note that amplifiers are sometimes referred to as kickers, amps, heaters, helpers, linears.

6 TVI: Television interference. Generally caused my mis-tuned radios, antennas mounted too low, excessive power, poor quality video and audio equipment.

Stealth antenna 03 Stealth Antenna 01

Build Stealth Antennas

Build Stealth Antennas

Building stealth antennas to keep prying eyes from detecting your communications resources takes some skill and a lot of ingenuity. The skill part comes into play when it comes down to building antennas that will be sturdy and will perform optimally for the frequency/band desired. The ingenuity part of a stealth antenna comes about when it comes to hiding the antenna from nosy people with nothing better to do than to concern themselves with YOUR antenna. A lot of survivalists and others who want to hide their communications antennas think that mostly wire antennas are the type of antennas used the most and for the most part that’s fairly true. But that doesn’t mean that your HF/VHF/UHF beams and vertical antennas can’t be also hidden. In this picture to the right, you can see how easily a multi-element VHF beam was hidden in the average looking attic of this home. Admittedly it may not work as on receive or transmit as well as it would if it was mounted higher up on the outside Stealth Antenna 01of the home but it is thoroughly hidden away in the attic. Since this antenna is directional it has the characteristics of other beam antenna in that the transmit signal is higher in strength along with it having the ability to better receive signals that might otherwise be too weak to hear.

What Other Ways Can Be Used?

There are many but here are a a couple ideas to get your “idea factory” working on your own stealth antenna ideas.

This type of stealth antenna has been discussed elsewhere on this web site but it was decided that it should be included on this page. Can’t see the antenna yet? Just take a look at Old Glory wafting in the breeze and Stealth antenna 02you will see the antenna. Give up? It’s the flagpole! These flagpole vertical antennas are popping up all all over the place, especially where outside antennas are restricted or forbidden altogether. If you wish to erect any sort of flagpole antenna such as this one then you might want to be sure there aren’t restrictions on flagpoles in the area where you wish to erect it. Some homeowner associations have an even more restrictive policy towards communications by stating that no radio emissions are allowed. Of course this would not apply to shortwave listening but it is best to check first. The flagpole antennas are permanent as they require a concrete base under them and this might keep them from being used in some survivalist situations.

Stealth antenna 03

The owner of this home has built a loop antenna that literally circles his house and no one is the wiser. Take note of the coax exiting the attic vent and running over to the balun1 which is connected to the wire running around the eaves of the house. Wire loop antennas like this one are quite effect and stealthy as well. Along with this is the fact that loop antennas tend to be broadbanded and can readily used on more than one band.

Well, about the time you think you have seen it all there comes around something like the Stealth antenna 04antenna to the right of your screen. It is manufactured by Rohn Products and should hide any antennas systems contained within fairly well. Of course it will also tend to make people stop and point thereby drawing more attention to it than one might desire. Nevertheless, it shows what can be done to hide your antenna.

1 Balun: Derived from the terms “balanced” & “unbalanced”. It is an adapter that converts an unbalanced signal, eg 93 ohm coax to 100 ohm.

Super Stealthy Antenna Ideas

Super Stealthy Antenna Systems

Stealth is good for hiding antennas for your survivalist communication systems from HOA (Home Owners Associations), nosy neighbors and possibly government vehicles looking for such communications systems. These Super Stealthy Antenna Ideas will help you find an antenna design you need.

While it can be said that the antennas mentioned in these articles are every bit as good as those antennas exposed free and clear out in the open. But that simply is not they case.

Shortened and hidden antennas almost always give up something in the way of performance when compared against their exposed cousins. But you must remember that these particular antennas are meant to prevent anyone from seeing them. They are in the true sense of the term – stealth antennas.


If you don’t have to keep your communications antennas hidden then that’s fine. But we all know that a day is coming where we will all be trying to hide some form of antenna.

In these following articles you will see antenna designs that seem to defy things that you know about ham and communications antennas. And yet the work!

Even today’s commercial antenna designs were most likely met with skepticism when they were first introduced to the communications community. Today they are among the world standards in antenna design and operations.

Take a look at the articles and see if there isn’t at least one idea that you as as survivalist could use at your home QTH or a remote camp of sorts.

You may notice that the vast majority of the steah antennas (or portable antennas) are made of simple such as you likely have on hand. Some purists and antenna “experts” will have you to believe that wire antennas don’t work but they can’t back up their claims with facts.

The main issue with wire antennas is that you need something to support them. Even wire vertical antennas require supports of some fashion or another.

k9ay delta loop antenna



Antennas play a vital part in any communication system and for more than the obvious reason that the radio simply won’t work without one. Radios, 2-way radio and receivers alike, can work with less than optimal antennas connected to them. But you will soon realize that the performance of the radio will also appear to be less than optimal. Ham radio operators are constantly working on and improving their antennas because they realize the importance of a fine tuned antenna. The ham operators even have a rule of thumb of sorts: “a dollar spent on the antenna is worth ten dollars spent on the radio”.

So where do antennas fit into a radio system used in a survivalist situation? The best answer to that question is yet another question which is ‘what do you want your radio to do?’. If you are looking for reception (and possibly transmission) of signals between countries or continents then you will be looking at a high performance HF1 antenna system. If you only need local or interstate communications then you can still use HF radio but with an antenna with less antenna gain.

Antenna gain. That’s likely a new word here for those interested in survivalist communications. Antenna gain is best explained by stating that an antenna can actually increase the power of a radio’s output signal. And by the same token you will enjoy better reception when an antenna has more gain to it. Without getting too technical you can read the specifications on a particular antenna and use the rough formula of 3db2 of antenna gain will give you twice the power output that you are feeding it from your transmitter. This means that theoretically you could feed 100 watts of power into an antenna with gain of 3db and it will appear to be 200 watts to those receiving your signal. So look at the gain of any antenna you contemplate using to see if it has a specification for gain. For each 3db of gain you get double the power, if your antenna has 9db of gain then your signal will sound like it is 300 watts.

Antenna types. This alone warrants a page alone. Antenna types for both almost all radios fall into these general categories:

  • Vertical (includes multi-element vertical beams)
  • Horizontal (includes multi-element horizontal beams)
  • Wire
  • Dish

Vertical antennas are just that, the antenna goes from the ground, or the mount, in an upward fashion.

Horizontal antennas run side-to-side and are usually found highBeam antenna up on top of towers or pushup masts with a rotator on it used to aim the antenna.

Wire antennas can be horizontal when hung between two or more supporting structures. Wire antennas are generally looked down upon as solid performers but we are looking more for portability, durability, and “stealthiness” when considering a wire antenna for use in a survivalist environment. That being the case you would be hard pressed to find another antenna that will fit all of these issues.

Most everyone knows what a dish antenna looks like, you only need to realize it is used for microwave radio frequencies and are unlikely to be used in survivalist environments.

Many have seen the various different types of antenna systems mentioned here without giving thought to one day using them as an survivalist.

We have more information about antennas available from the links at the bottom and right side of this page. The information contained on the links at the bottom are the same pages as those on the right side of the page. They were placed in two different spots to make the information easier to access.

1HF when used to describe radio equipment refers to the High Frequency bands.

2db or DB stands for decibels and is a logarithmic unit of sound intensity.