The following notes highlight some of the main requirements in caring for radio control equipment. They have deliberately been kept brief so please seek the advice of the committee or an experienced flyer if you need clarification.

  • TYPE APPROVAL

Transmitters must have either a Type Approval sticker or a CE mark. Without this they are illegal to use in the UK, may interfere with other peoples’ models and invalidate your BMFA insurance. Beware of cheap imports which do not carry either of these labels. They are on sale over the Internet and at swap-meets and shows.

  •  INSTRUCTIONS

 Read and follow the manufacturers’ instructions.

  •  FAIL SAFES

 If your radio has a fail-safe you must check that the throttle is set to tick-over (off in electric models). This is particularly important if you reverse your throttle servo. Throttle fail-safes dramatically reduce the risk of serious injury in the event of  radio problems. Add-on throttle fail-safes are available for PPM equipment at a cost of under £15.  

  •  SERVICING/REPLACEMENT

 Modern radio is very reliable but  follow the manufacturers’ instructions on servicing.  Have your equipment professionally checked following a heavy crash.  It may be more cost-effective to replace standard servos and receivers than have them serviced. If you continue to fly with older equipment have it tested regularly and keep your receipts. If the worst happens and you injure someone you may be called upon to demonstrate that  you took all reasonable care before flying.

Beware of buying second-hand crystals and batteries unless you know their history. These are among the more common causes of radio failure and are relatively cheap to buy new.

  • TRANSMITTERS

Handle your transmitter with care and keep it clean. After every trip to the flying field, wipe it with a soft, dry cloth or paper towel. Pay particular attention to the area around the sticks. Fuel is corrosive - it will soften the plastic and damage metal parts. Over time, fuel exposure will make the radio case brittle and allow plastic parts to break easily. Always keep your radio away from the engine's exhaust stream.

Never pick the transmitter up by the aerial and never oil the aerial. Clean it with an alcohol-based cleaner. Periodically unscrew the aerial and clean the threads of the connector. (Condensation can run down and cause corrosion at this point).

If the sticks become stiff do not oil them. Their bearings have probably become worn and should be serviced professionally. Occasionally unplug and replace the crystal (and module if fitted). This helps keep the pins clean.

Always extend your aerial to at least the bottom segment when turning the radio on. If you leave the radio on with the antenna collapsed for more than 5 to 10 minutes, the internal components will be unnecessarily exposed to incorrect matching of the output circuit to the antenna. This may shorten the life or even immediately damage the output circuitry of the transmitter. This advice is particularly important when setting up a model or experimenting with a new transmitter.

  • RECEIVERS

2.4 receiver aerials are fragile. Regular checks should be made to the integrity of these antennas. Ensure you have charged your rx pack sufficiently as brown outs occur around 3.5v.

  • SERVOS

The two main enemies here are vibration and poorly fitting linkages. Servos should always be fitted with rubber grommets so that no part of the servo touches the airframe. Do not over-tighten the mounting screws. Linkages must be free as any binding will cause servo wear and rapidly drain the battery (listen for buzzing). It is equally important that there is no excessive play in the linkages especially if using digital servos. Standard servos don't notice common problems like slop at neutral, but a digital servo will and, in the process of struggling to hold the control in position, it will quickly drain your battery and eventually ruin its motor.

  • SWITCH AND WIRING

Switch problems are one of the commonest causes of crashes because they are often mounted directly on the outside of the fuselage and so are exposed to vibration and exhaust. If possible mount the switch on a servo tray which is supported by rubber grommets and operate it by a wire rod through the fuselage side. If it must be mounted outside then place it on the opposite side from the exhaust.

Wiring should be supported and it is a wise precaution to tape the battery to switch connector. Pay attention to plugs which are disconnected after every flying session (e.g. aileron connector) to make sure that the soldered joints are sound and that the pins are not worn.

Peel back the insulation slightly on the black wire connecting to the battery to check for black wire corrosion. If this has a black and powdery surface the wires should be replaced. Better still, replace the switch and associated wires every two or three years. Heavy duty switches cost only a little more and are much more robust.

  • BATTERIES

Follow manufacturers’ instructions. Always fully charge before flying. Recycle nicad batteries occasionally, especially if your flying sessions are short and the batteries are only partly discharged. This helps overcome the ‘memory effect’.

If you fast-charge your batteries NiCads should only be charged at around 2.5 times their capacity and NIMH batteries only around 1.5 times,

Check occasionally for black wire corrosion (see above). In relation to the cost of an entire model and the risk of injury in the event of a crash, batteries are relatively cheap and are worth replacing every two to three years. (Packs can be split and the cells used to power toys, radios, torches etc until they finally fail to hold their charge)

  • STORAGE

If you are unlikely to fly a model for some time disconnect its battery and store the model somewhere dry. Similarly unplug transmitter batteries if you do not intend to fly for a while.