In 1982, the present 72 megahertz (MHz) frequencies were assigned for model airplane use. A similar set of 75 MHz frequencies was placed in service for surface use. The seven frequencies formally used by modelers (72.080, 72.160, 72.240, 72.320, 72.400, 72.960, and 75.640 MHz) were shared with commercial users; these were grandfathered for five years and formally phased out in March 1987.

Not only is the use of those frequencies illegal for models now, it should be understood that they are assigned to high-powered commercial users.

Furthermore, the use of these frequencies by AMA members is a violation of the Academy's Safety Code.

By 1991, all of the present 72 MHz model frequencies presently used were phased into service. The Academy, working in conjunction with the FCC and Radio Control Manufacturers Association (RCMA), promulgated guidelines that created so-called "narrowband" transmitters and receivers. A program to narrowband older equipment was put into place, as well as an identification program for transmitters that were manufactured (or modified) to narrowband specifications - they were identified by a gold sticker.

When the narrowband specifications became a requirement for the manufacturers, the gold-sticker program was phased out. Any transmitter purchased since March 1, 1993 is required by law to be narrowband.

Note that receivers have not been mentioned relative to the FCC regulations, phase-in, stickers, etc. In a simplistic form, the FCC is concerned about what goes into the air, not what is taken out. They control radio frequency (RF) emissions in an attempt to make the system work. If the receiver you use has poor selectivity, and causes problems in operating your model properly, that's your operational problem (granted, that poor receiver can create a safety issue)!

When the Academy promulgated the equipment guidelines, it included receivers, and industry voluntarily followed those guidelines — the system works!

On March 1, 1998, older "wideband" transmitters were no longer legal by FCC regulation. While no like regulation exists for receivers, it should be understood that continuing to operate older wideband receivers created considerable risk of interference and resulting crashes.

There is one receiver regulation that went into effect March 1, 1999. It deals with receiver emissions and affects the equipment manufacturer. All receivers manufactured before the 1991 date, though, are legal and are grandfathered forever.

As a newcomer, how does all of this affect you? If you are purchasing new radio equipment, it doesn't! What is being sold now, and what has been sold for the past several years, meets all of the FCC regulations and should not cause you any problem. However, if you elect to purchase used equipment, the factors above need to be considered. A snap decision at a swap shop may result in a problem. Here are some guidelines:

1) Is the brand still being sold or serviced? By whom?

2) If manufactured before 1993, does the transmitter have a gold RCMA/AMA sticker?

3) If #2 is yes, was the transmitter narrowband at manufacture or was it updated at a later time?

4) Is the receiver narrowband? Many older updated systems will utilize newer aftermarket receivers. Check to see if the receiver states that it is narrowband, but be aware that some very early receivers were marginal.

5) Is the system AM, FM, PCM, or PPM? If it's AM, check to see if the receiver is "dual conversion." If so, fine! If not, proceed with caution, especially if the receiver doesn't say it is narrowband. If it's FM, PCM, or PPM, you should not have a problem with it being a narrowband system.
(One manufacturer uses the term "ABC&W." This denotes a system that fully meets the guidelines, but may not technically be said to be dual-conversion.)

6) Has the system been used or charged regularly?

7) Systems on 27 MHz are legal to operate for airplanes or surface use. They are not recommended for airplanes because of the potential for interference from Citizens Band (CB) operations and they are not subject to the narrowband regulations.

8) Do not purchase or operate a unit on the amateur ("Ham") bands 50 or 53 MHz unless you possess a valid amateur license. If you are a Ham, check to see if the club you are joining has a properly licensed individual who can instruct. Operation of equipment on 50 or 53 MHz by an unlicensed individual is illegal.

A ruling by the FCC in 1980 stated that while a nonlicensed individual may operate two-way communication equipment with the immediate supervision of a licensed individual, the same condition does not exist for radio control operation.

9) Read the radio section in your Membership Manual. It explains many of these complicated issues and provides some simple tests to determine whether a system is narrowband.

Other questions come to mind when you are looking into buying equipment. You'll find a wide range of costs for new sets, from the most inexpensive set (at a little more than $100) to more than $1,000.

What should I buy? How many channels should I get? Consider the radio to be a long-term investment. Even if your model uses less than the four typical functions (elevator, aileron, rudder, and throttle) you will probably be better off with a set that has at least four channels of operation.

It may not be long before you would like another channel or two for auxiliary functions (flaps, retracts, etc.) Radio-channel functions are like engine horsepower — you can't use what you don't have! And trying to sell what you do have, to get more, is costly.

What transmitter mode should I buy? Transmitters generally come in one of three modes; these are designated as mode I and mode II (both with two control sticks) and single-stick. The largest number of sets are sold as mode II. In mode II, you will find the elevator and aileron on the right stick and the rudder and throttle on the left.

In mode I, the elevator and aileron are on separate sticks. The purpose of this is to minimize the interaction between the two, since they are the controls primarily used in flight. In the single-stick type, the three surface controls (elevator, aileron, rudder) are on one stick and the throttle is a slide-type switch on the side of the transmitter case.

Which transmitter type is right for you? A deciding factor could be availability. Single-stick equipment is generally only found in the upper price range and in limited numbers; you'll probably have to order it, if you can find it at all. In a like manner, mode I will be harder to locate.

The key factor is finding someone to help you learn to fly with single-stick or mode I! Yes, there are instructors who can make the transition from one mode to another, but remember: flying a model is like operating an automobile. In a pinch, it's the old reflex that takes over. If an instructor is forced to teach you to drive, and you gave him/her a car with the brake and accelerator reversed, it might make for an exciting session when he/she drives! Check out the availability of equipment and instructors.

(Another factor may be whether you are right- or left-handed - Which modulation form should I buy? We're not going to go into a technical discussion of the forms of modulation here, but you will find very strong preferences in the field regarding whether you should buy AM, FM, PCM, etc.)

As sets progress in price, they tend to move from AM to FM, and so forth. The implication clearly becomes that one form of signal modulation is better than another. More often than not, the "better than another" consideration centers around freedom from interference. The bottom line is that, for general purposes, you are looking for a good, solid radio link between the transmitter in your hands and the receiver in the model. This can be achieved with any of the modulation forms.

How much should I spend? This is one of two questions impossible to answer. What perhaps needs to be asked is: how much do you have available to spend? The newcomer often feels reluctant to invest too much money because he/she is not certain this hobby/sport will "take" for them. As a result, their first impulse is to spend as little as possible. Does it seem logical to skimp on the radio system? Remember, that's what is going to get your $250 model and engine, that you spent many hours putting together, up and down safely! Don't let the radio system be an afterthought. It's an investment that more likely than not will outlive the airplane.

You may wish to consider the newer computer radio systems. With them, you can operate several models from one transmitter. While you still have to purchase an airborne pack for each model, you save the cost of multiple transmitters.

Which channel should I buy? First of all, understand that the term "channel," as applied to where the system operates in the radio spectrum, should read "frequency." The FCC granted modelers the use of 50 frequencies in the 72 MHz range; each frequency was then assigned a channel number from 11 to 60. They are much easier to remember that way. Most manufacturers place the channel designation and the frequency on the equipment stickers. It really is a good idea to memorize both of these for use at the field.

I was called upon to mediate a "debate" when a modeler's airplane was shot down, because two models were on the same frequency. It seemed that the two parties involved didn't communicate in the same language and failed to recognize that channel 40 is the same as 72.59 MHz. They do now!

Check with the local club and find out which channel is used least. It will probably be an odd channel number, since they're the newest numbers added. Check with the local hobby shop as well, for any help they can provide. If there are some high-powered, industrial transmitting towers in the area, you may wish to steer clear of the frequencies on either side of theirs. You may have a problem trying to identify their frequency; however, local clubs may have already monitored and discovered what is in the area.

What brand should I buy? This is the second question impossible to answer. You've gone through this routine in purchasing other things. When you were in the market for a refrigerator, you found that the neighbor on your right swore by a GE (TM), while the neighbor on your left swore at a GE (TM)!

The use of a certain radio brand in any given area is usually driven by two factors: what the expert (or instructor) at the field recommends, and what the hobby shop stocks. These two tend to be very much interrelated. It would be great if we could refer you to a copy of Consumer Reports, but that's not possible. From time to time, radio systems are reported on in magazines; however, there is no standardized format or comparative figures.

There are factors you need to consider beyond cost. For instance, the availability of repair facilities is important. Try to discover how long it takes for equipment-repair turnaround, especially during the summer months. If it takes a couple of months, that might amount to a big percentage of the flying season in some parts of the United States.

How about the availability of parts? Can you pick up a switch harness at your local hobby shop? How about interchangeability with other brands? The last several years have brought us closer to interchangeable plugs, etc. How many "bells and whistles" should I buy? As a newcomer, many of the extras found on some systems (such as function mixing and a snap-roll button) may not be needed for your flying.

On the other hand, servo-reversing switches, while not a necessity, can be useful - even for a newcomer. Rate switches can also be useful. Low rate can be used on the rudder during takeoff to cut down on the problem of overcontrol.

How about a computer-controlled system? It's true that they can do a lot of things, including storing setups for more than one model. It's your call; just don't become so enamored with playing with the transmitter that you forget to build and fly the model!

Where does it all end?

There are still probably a host of other questions you'd like to ask about radios. Please understand that the world of the radio wave is very dynamic. The impact of communication development on our lives has been very dramatic. This is true in the hobby/sport, as well.

Five years is a lifetime, in some ways. In fact, the FCC often uses this time frame to denote complete equipment generations. As a newcomer, you probably don't feel the need to be on the cutting edge of technology. A good, solid, dependable system that helps you steer your model through the air is your primary concern now. Ask a lot of questions and weigh the responses carefully.