NewComers
Box 40, St. Peters MO 63376
For the newcomer interested in R/C, one of the most difficult decisions in the learning process is selecting a radio system. Below are a number of questions and considerations to help you decide.
Should I buy a used system?
When working on a tight budget, buying a used system is a possible solution. But be careful. Over the years there have been a number of changes in radio spectrum usage. The most recent of these occurred within the last five years, when we moved from "wideband" equipment to the present "narrowband" format. Beyond making certain that your used find is in good condition, it is important to determine whether you can feel comfortable using it without fear of interference.
Ask the following questions about the system:
- How old is it? If it's more than five years old, find out if the transmitter was narrowbanded. It may carry a gold R/CMA/AMA sticker. The sticker — a parallelogram roughly 3/8 x 1 1/2 inch — means that it meets narrowband specifications. The presence of the gold sticker does not necessarily mean that the receiver is narrowband.
- Have the batteries been kept charged? New batteries could easily add up to a cost roughly equal to half the cost of a new set.
- Is it on a legal frequency? If the set is on 72.080, 72.160, 72.240, 72.320, 72.400, 72.960 or 75.640 MHz, it cannot be legally operated in the United States. Those frequencies became illegal for model use in 1987, and old-style wideband transmitters became illegal as of March 1998. Besides being illegal, those frequencies are assigned to a variety of higher-powered commercial users.
- Has it been crashed? Perhaps the question should be, "How often?"
- Has it been serviced? How frequently?
Please understand that a non-narrowband system may not be a problem as long as it operates on a legal frequency. However, you need to check and see if the rules for the flying site you'll be using allow all 50 frequencies in the 72 MHz range. If the answer is "no," then an older system may not be allowed. If you will be flying near a metropolitan area, you will be operating at a higher risk level from both modeler-to-modeler interference and other sources. A set on 27 MHz is legal, but it's likely to be very susceptible to interference. Do not buy or operate a set on 6 meters (the ham band) unless you hold a valid FCC amateur license.
If used equipment is not for you, check the ads. You will find sets from about $100 to more than several hundred dollars.
What to buy — stick mode, channels, modulation and features
Consider a radio a long-term investment. If your first model uses no more than four typical functions — elevator, aileron, rudder and throttle — you'll probably be better off with a set that has at least four channels. You may be using that radio a long time before you want another channel for auxiliary functions such as flaps or retracts. Radio channel functions are like engine horsepower: you can't use what you don't have.
What transmitter mode should you buy? Transmitters generally come in three modes designated Mode I, II and III.
- Mode II (two control sticks) is the most common. In Mode II you will find elevator and aileron on the right stick, and rudder and throttle on the left.
- Mode I places elevator and aileron on separate sticks to minimize interaction between the two since those controls are primarily used in flight.
- Single-stick types allow three surface controls (elevator, aileron, rudder) on one stick, with throttle as a stick or slide control and switches on the side of the transmitter case.
Which is right for you often comes down to availability and instruction. Single-stick equipment is generally found in the upper price range and in limited numbers; you may have to order it and find an instructor who can help you learn in that mode. Instructors can teach transitions between modes, but you should consider how comfortable you will be learning and flying with different control layouts.
What modulation form should you buy? You will find strong preferences for AM, FM, PCM, and other forms. As sets increase in price they tend to move from AM to FM and beyond, which often correlates with greater freedom from interference. For general purposes, what you are looking for is 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.
A common discussion among manufacturers and flyers is about features like fail-safe. Some prefer fail-safe settings that move the model to neutral controls on interference, while others prefer to try to regain control. In severe interference, fancy features mainly let you try to crash more gracefully.
Most systems (other than very inexpensive ones) use a receiver known as dual conversion. Manufacturers often use this as a selling point for reduced interference. However, other receiver designs that are not technically dual conversion can perform just as well — don't rule them out simply because someone says only dual conversion is acceptable.
How much should I spend? This depends on how much you have available. Newcomers often hesitate to invest much because they are not certain the hobby will "take." But remember: the radio system is what will safely get your $250 model and engine up and down. Don't let the radio be an afterthought. It's an investment that will likely outlive the airplane.
Which channel should I buy?
Please understand that the term "channel" as applied to where in the radio spectrum the system operates really means "frequency." The FCC granted modelers the use of 50 frequencies in the 72 MHz range. Each frequency was assigned a channel number from 11 to 60 because numbers are easier to remember. Most manufacturers place both the channel designation and the frequency on the equipment stickers — it's a good idea to memorize both for use at the field.
Check with your local club to find out which channels are least used. Odd channel numbers are often less used because they were added later. Some club sites do not allow odd channels because members are still operating older equipment. Check with the local hobby shop as well.
If there are high-powered industrial transmitting towers in the area, you may wish to steer clear of the frequencies just on either side of theirs. Local clubs may have already monitored and discovered those frequencies.
I was once called to mediate when a modeler's airplane was shot down because two models were on the same frequency. The 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.
Which brand should I buy?
Brand choice is often driven by two local factors: what the expert or instructor at the field recommends, and what the hobby shop stocks. These tend to be interrelated. There is no standardized comparative information like Consumer Reports for radio systems, so local experience matters.
Consider factors beyond cost:
- Repair facilities: how long does turnaround take, especially during the summer months? A couple of months for repair might be a large portion of the flying season in some areas.
- Parts availability: can you pick up a replacement switch harness at the local hobby shop?
- Interchangeability with other brands: are components and accessories compatible?
How many "bells and whistles" should I buy?
As a newcomer, many of the extras on some systems may not be needed. Function mixing and a snap-roll button are examples of features you may not use right away. On the other hand, servo reversing switches are very handy for setup. Rate switches, while not necessary, can be useful — for example, using low rate on the rudder during takeoff to reduce overcontrol.
Computer-controlled systems can do a lot, including storing setups for more than one model. They can be useful, but don't become so enamored with playing with the transmitter that you forget to build and fly the model.
And where does it all end?
There are still many questions you might ask about radios. The world of radio is very dynamic: communications development impacts the hobby dramatically. Five years can be a lifetime in this field, and the FCC often uses that timeframe to denote complete equipment generations.
As a newcomer, you probably don't need to be on the cutting edge. 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. One of the best guides is to observe what is successful at your local flying site. That, combined with your future goals, will help you decide what comes next.
Transcribed from original scans by AI. Minor OCR errors may remain.
