People often confuse radio control (R/C or RC) with remote control. R/C always means “radio control” and never “remote control.” R/C vehicles are controlled by a wireless transmitter which sends signals to the vehicle via radio waves. They have an antenna on the transmitter which is usually telescopic and an antenna on the vehicle itself. Remote control vehicles are linked to their transmitters by a wire. RC vehicles therefore have far greater range and are able to travel at higher speeds.
Frequency vs. Band
All transmitters (car radios, garage door openers, cordless telephones) send or receive radio signals. However, these devices do not all operate on the same frequencies. Otherwise they would all interfere with each other. A radio control frequency is a radio wave setting that prevents an R/C from interfering with other R/C vehicles or other radio signals. Frequencies are parts of bands, which are consist of a group of designated frequencies/ For example, AM Tx. 27025 is a radio frequency and is part of the 27MHz band.
A radio control band is a group of radio control frequencies that are very similar to each other. There are three band settings in the United States that the FCC has designated for R/C vehicles. These are 27MHz, 49MHz and 75MHz. However in other countries such as China or Japan more radio bands are available, such as 29MHz, 35MHz, and 40MHz. So some imported R/C toys may use these frequencies as well. When buying an RC vehicle and have in mind driving with a companion, look for a label on the box that says either “27MHz,” “49MHz” or “75MHz.”
In most micro R/C toys it is impossible to change the frequency within a certain item. However, in larger items such as 1:10 scale R/C cars you can remove the frequency crystal and change it in order to drive with up to six other people within the same band. For example, if you change the 27025 frequency crystal to 27095, you are changing the frequency within the band. Radio transmitters and receivers are only compatible with one band so a 27MHz transmitter will not function with a 49MHz crystal.
Infrared Controllers
Infrared controllers are unlike radio transmitters because instead of sending radio signals, they use infrared light, similar to a TV remote. Infrared transmitters must always be in the line of sight of their vehicle because if the vehicle cannot see the light, they cannot communicate. It is often best to point the infrared light bulb directly at the vehicle. Digi-Q cars and tanks use infrared control.
Functions
Full function R/C vehicles have the ability to move forward, reverse, left and right. Most of the R/C cars that we carry are full function. Other R/C cars may have only two functions, forward and reverse. These cars can turn one directing only when they move in reverse.
Range
Radio control vehicles have a certain range of distance from their operator in which they are able to function. With larger R/Cs this range can be increased by buying a better transmitter or receiver. The range of micro R/Cs can sometimes be increased by performing antenna modifications.
Scale
Scale is the ratio of the size of a model vehicle in comparison to its full-size counterpart. Scale is measured by the length of the chassis of a vehicle. If a model vehicle is 1:24 (or 1/24th) scale, then it is 1/24th the size of its full-size counterpart. The smaller the fraction, the smaller the item. Some of our smallest items are 1:64 scale, our larger items can be up to 1:8 scale.
Steering
Some of our micro R/C cars have non-proportional or regular steering. This means that the vehicles can turn left or right but have only one turning radius. All of our larger RC vehicles have digital proportional steering which is similar to that of a real car. The steering is sensitive and precise. The wheels will turn a certain amount depending on how far the steering on the controller is moved. This sensitive steering allows sharp or wide turns and helps prevent these vehicles from flipping or losing control.
Gear Ratios
A gear ratio is the comparison in the number of teeth of the spur gear to the number of teeth of the pinion gear or how many times the pinion gear must rotate for one spur gear rotation. The higher the ratio, the more low-end torque and acceleration the R/C car will have, but it will have a lower top speed. The lower the ratio, the more high-end speed a car will have, but it will have less acceleration power. A gear ratio is always measured by some number to 1. For example, a ratio of 12:1 will have more low-end torque than a ratio of 6:1, which will have more high-end speed.
A gear ratio can be changed by getting different gears. A car cannot have both the highest possible acceleration and highest possible top speed unless it has a multi-speed transmission. A proper gear setting depends on the kind of terrain on which a vehicle is being operated.
Batteries
All R/C items have varying battery requirements based on their features, performance or size. Some smaller vehicles require “AA” or “AAA” size alkaline batteries while most others require Ni-Cd (nickel cadmium) or Ni-Mh (nickel metal hydride) batteries. Batteries come in different sizes, amperage and voltage. Transmitters almost always use “AA” batteries.
Ni-Cd vs. Ni-Mh
Ni-Cd stands for the atomic symbols of the metals nickel and cadmium. Ni-Mh stands for nickel metal hydride. Unlike alkaline batteries, Ni-Cd and Ni-Mh batteries are rechargeable. Ni-Mh batteries do not have cell memory like Ni-Cd batteries meaning they can be recharged at any time without having to fully discharge the batteries. Usually charging a Ni-Cd battery without fully discharging it can damage the battery and decrease its capacity. Ni-Mh batteries often last longer than Ni-Cd batteries but may give a smaller voltage output.
Charging Batteries
Battery packs must be charged before use otherwise they cannot output power. For the best performance and battery lifetime, Ni-Cd batteries should be fully discharged before recharging. General safety tips for charging batteries:
- Always read the instruction manual of the battery and charger before charging.
- Never overcharge a battery pack as it can cause damage to the battery and possibly catch fire.
- Never charge a damaged battery pack because it may catch fire.
- Never cover a battery with any sort of material while charging and keep it clear of other objects.
- Always keep the battery and charger away from any liquid.
- Battery pack will be warm after charging and hot after running a vehicle, handle with care.
- Wait until a battery pack cools before installing it in a vehicle or charging as a hot battery pack can damage itself or other objects.
Battery Life
If carefully maintained, a battery pack will survive hundreds of charges and discharges. If a battery pack is overcharged or charged without fully discharging its charge time and total life time may be shortened.
General RC Safety Tips
- Read the owner’s manual before operating an R/C vehicle or charging a battery.
- Do not overcharge a battery pack.
- Do not charge a damaged battery pack.
- Keep a charging battery away from other objects.
- Never cover a battery with any sort of material while charging.
- Always charge in a dry area, keep the battery pack and charger away from any liquids.
- Battery pack will be warm after charging and hot after powering a vehicle; use care when handling.
- Wait until a battery pack cools before installing it in a vehicle and before charging.
- Never run a vehicle in water and keep it away from any liquids.
- Always turn your transmitter OFF before handling a vehicle.
- Do not use multiple vehicles on the same frequency at the same time.
- Note child age usage recommendations on the product boxes. Children under 8 years of age should have parental supervision when using R/C toys.
Troubleshooting Tips
Problem: Vehicle does not respond or functions erratically to transmitter commands. Potential causes:
- Weak or low quality batteries in the transmitter or vehicle. If the transmitter is unable to send solid signals, it can cause the car to respond in unexpected ways or not respond at all. If the vehicle’s battery is weak then it may function erratically.
- Incorrect battery installation.
- Vehicle is beyond the range of the transmitter.
- Radio interference from another device on the same frequency: another R/C vehicle, two-way radio, cordless phones, electric transformers, garage door openers, etc.
- Replace batteries with fresh, high quality alkaline batteries. Use a high-quality rechargeable battery pack (if compatible.) Fully recharge the battery pack after fully discharging.
- Ensure that all batteries are installed correctly and connected with their proper terminals. Ensure that the battery pack is plugged in to the vehicle.
- Fully extend the transmitter antenna. Walk toward the vehicle and operate it in a shorter distance away from the transmitter.
- Turn off other devices on the same frequency or move to a location further away from them.
Potential causes:
- Weak or old battery pack or batteries.
- Vehicle and/or transmitter have been left on for an extended period of time when not in use.
- Battery pack has not been fully charged.
- Always turn the vehicle and the transmitter OFF when not in use.
- Replace batteries with fresh, high quality alkaline batteries. Use a high-quality rechargeable battery pack (if compatible.) Fully recharge the battery pack after fully discharging.
- Always fully discharge a battery pack before charging it.
- Never overcharge a battery pack.
- Replace the battery pack if it has been damaged.
0 Response to "Beginners' R/C Guide"
Post a Comment