Newcomers

Newcomers

Bob Underwood

BOX 40, St. Peters MO 63376

Introduction

For the newcomer interested in Radio Control (RC), one of the most difficult decisions in the learning process is selecting a radio system.

This column gathers information from two previous columns (May 1995 and February 1997) and updates it, especially as it relates to Federal Communications Commission (FCC) activity.

Frequency background and FCC action

• 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; they were grandfathered for five years and formally phased out in March 1987.
• Use of those frequencies is now illegal for models; they are assigned to high-powered commercial users. Use by AMA members is also a violation of the Academy's Safety Code.

By 1991, all of the present 72 MHz model frequencies in current use were phased into service. The Academy, working with the FCC and Radio Control Manufacturers Association (RCMA), developed guidelines creating so-called "narrowband" transmitters and receivers.

A program to narrowband older equipment and to identify transmitters manufactured (or modified) to narrowband specifications was implemented — these transmitters were identified by a gold sticker. When narrowband specifications became required for manufacturers, the gold-sticker program was phased out. Any transmitter purchased since March 1, 1993 is required by law to be narrowband.

Note: the FCC regulation emphasis has been on transmitter emissions — what goes into the air. Receivers are not regulated in the same way by the FCC; poor receiver selectivity is an operational issue that can create interference and safety problems. When the Academy promulgated 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 similar regulation exists for receivers, continuing to operate older wideband receivers increases the risk of interference and resulting crashes.

One receiver regulation did go into effect March 1, 1999. It deals with receiver emissions and affects equipment manufacturers. All receivers manufactured before 1991 are legal and are grandfathered indefinitely.

What this means for the newcomer

If you are purchasing new radio equipment, you generally do not need to worry: current equipment meets FCC regulations. If you are buying used equipment, however, consider the history and condition carefully. A snap decision at a swap meet may lead to problems. Guidelines to follow when buying used equipment:

1. Is the brand still 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 updated later?
4. Is the receiver narrowband? Many older updated systems use newer aftermarket receivers. Check whether the receiver is stated to be narrowband, but be aware some early receivers were marginal.
5. Is the system AM, FM, PCM, or PPM? If it's AM, check whether the receiver is "dual conversion." If so, fine; if not, proceed with caution, especially if the receiver doesn't state 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 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 but are not recommended for airplanes because of potential interference from Citizens Band (CB) operations. They are not subject to 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 whether the club you are joining has a properly licensed individual who can instruct. Operation on 50 or 53 MHz by an unlicensed person is illegal. A 1980 FCC ruling stated that while a nonlicensed individual may operate two-way communication equipment under the immediate supervision of a licensed individual, that exception does not apply to radio control operation.
9. Read the radio section in your Membership Manual. It explains many of these complicated issues and provides simple tests to determine whether a system is narrowband.

Other buying considerations

• Price range: New sets range widely in price, from a little more than $100 to more than $1,000.
• Channels: Consider the radio a long-term investment. Even if a model initially needs fewer than four functions (elevator, rudder, aileron, throttle), it is wise to get at least a four-channel set. You may soon want extra channels for flaps, retracts, etc. A radio with more capability will also command a higher resale price.
• Transmitter types: There are several types — single-stick, single-stick with throttle on the left, and two-stick (Mode I and Mode II). The trend is toward left-hand throttle (Mode II), but the choice is personal. Single-stick and Mode I units are less common and may require special ordering. Find instructors and helpers who are familiar with the control layout you choose.
• Handedness and modulation: Your right- or left-handedness may affect comfort with stick layout. Regarding modulation (AM, FM, PCM, etc.), there are strong field preferences. Generally, as price increases, sets move from AM to FM to other forms. The primary concern is a solid, reliable radio link — this can be achieved with any modulation form when systems are well-designed.
• Computer radios: Newer computer-controlled radios can store setups for multiple models and let you operate several models from one transmitter. You still need an airborne pack for each model, but you save the cost of multiple transmitters.

Channels and frequencies

• The term "channel" commonly used at the field refers to a channel number assigned to a frequency. The FCC granted modelers 50 frequencies in the 72 MHz range; each frequency was assigned a channel number from 11 to 60 for easier reference. Manufacturers usually place the channel number and frequency on equipment stickers. Memorize both for use at the field.
• Always check with your local club to find which channel is used least. Newer (odd) channel numbers may be less used. Check with the local hobby shop too. If there are strong industrial transmitters in the area, avoid frequencies near theirs. Local clubs may already have monitored and discovered nearby transmissions.

Anecdote: I once mediated a dispute when one model was shot down because two models were on the same frequency. The parties didn't recognize that channel 40 is the same as 72.59 MHz.

Brand, service, and support

• Brand choice depends on local expert or instructor recommendations and what the hobby shop stocks. These factors are often interrelated.
• Consider availability of repair facilities and turnaround time — especially during summer, a long repair time can mean you lose much of the flying season.
• Check parts availability: can you get a switch harness at the local shop? Recent years have brought more interchangeability in plugs and parts.

Features and extras

• As a newcomer, many extras (function mixing, snap-roll button) may not be needed immediately.
• Useful features: servo-reversing switches and rate switches can help. For example, low-rate on the rudder during takeoff reduces overcontrol.
• Computer-controlled features are handy for managing multiple models, but don't get so absorbed in transmitter programming that you forget to build and fly.

How much should I spend?

This depends on how much you have available. Newcomers often hesitate to invest much until they are sure the hobby will stick. However, the radio controls your investment in the plane and engine — skimping on the radio can put that investment at risk. A good, dependable system is worth spending on, as it will likely outlive the airplane.

Where does it all end?

The world of radio is dynamic; five years can represent a complete equipment generation. As a newcomer you probably don't need bleeding-edge technology. Focus on a solid, dependable system that helps you steer your model safely. Ask lots of questions, weigh responses carefully, and observe what works successfully at your local site. Combining local experience with your future goals will guide your next choices.

Transcribed from original scans by AI. Minor OCR errors may remain.