question: How can a controller only control its own RC car if they are mass produced?
comment: In the old days of FM and AM radios, it was tricky. For RC aircraft, the 72MHz band was divided into 49 channels. Each radio would be given a crystal that was tuned to one of those channels. Obviously when you're making millions of the things, and there's only 49 channels to chose from, they're going to have to duplicate. Problem is that if someone on the same channel as you turns their radio on when you're flying, the receiver in the plane will get confused, and your expensive model is likely going to get lawn darted. Most AMA/MAAC sanctioned flying fields had strict frequency management rules as a result. Radios were to be kept in an impound shed when not in use to avoid accidental switching on. Frequency management boards were used to show what channels were available, and what weren't. But there was still room for human error, and accidents still happened. Those radios were also really prone to environmental interference. Around about 2006 or so, Horizon Hobbies introduced the first "spread spectrum" radios, that ran at 2.4GHz. A controller would be binded (paired) with the receiver in the plane, much like you would with a Bluetooth device. Once that's done, the radio automatically scans for available frequencies, and locks in to a free channel. If there's any interference, it can "hop" to another free channel, ensuring the model always has a stable connection with the controller, as long as there's power. A failsafe mode is also built in that keeps the model flying straight and level until it can reconnect, should there be a major issue. Thus taking out any possibility for human error. Spread spectrum has become the standard now for almost all radio controlled models.
passages: There are thousands of RC vehicles available. Most are toys suitable for children. What separates toy grade RC from hobby grade RC is the modular characteristic of the standard RC equipment. RC toys generally have simplified circuits, often with the receiver and servos incorporated into one circuit. It's almost impossible to take that particular toy circuit and transplant it into other RCs.
  
  Section::::Mass production.:Hobby grade RC.
   Hobby grade RC systems have modular designs. Many cars, boats, and aircraft can accept equipment from different manufacturers, so it is possible to take RC equipment from a car and install it into a boat, for example.
  
  However, moving the receiver component between aircraft and surface vehicles is illegal in most countries as radio frequency laws allocate separate bands for air and surface models. This is done for safety reasons.
   All unmanned aeronautical activities in Australia are ruled by CASR (Civil Aviation Safety Regulations) Part 101 which includes sections for UAV's and model aircraft among other operations. It is currently under review and new regulations specifically relating to UAV's and model aircraft are anticipated.
   Section::::Design.
  
  RC electronics have three essential elements. The transmitter is the controller. Transmitters have control sticks, triggers, switches, and dials at the user's finger tips. The receiver is mounted in the model. It receives and processes the signal from the transmitter, translating it into signals that are sent to the servos and speed controllers. The number of servos in a model determines the number of channels the radio must provide.
   While some companies make use of RC multicopters for low altitude aerial photography, filming, policing, and remote observation or inspection, RC helicopters are not commonly used for commercial purposes. One notable exception is crop spraying with large RC helicopters such as the Yamaha R-MAX.
   Because of interference from CB radios, legal or otherwise, the noise level, and the limited number of channels, most "serious" hobby radio-controlled models operate on other bands. Interference is especially important for model aircraft where it presents a safety issue.
   In aircraft, cars, trucks and boats, glow and gas engines are still used even though electric power has been the most common form of power for a while. The following picture shows a typical brushless motor and speed controller used with radio controlled cars. As you can see, due to the integrated heat sink, the speed controller is almost as large as the motor itself. Due to size and weight limitations, heat sinks are not common in RC aircraft electronic speed controller (ESCs), therefore the ESC is almost always smaller than the motor.
  
  Section::::See also.
  
  BULLET::::- JST connector
   Most radio control systems - traditionally on low-VHF-band frequencies, before the 21st century - have traditionally used crystals to set the operating channel in the receiver and transmitter. It is important that each aircraft uses a different channel, otherwise interference could result. For example, if a person is flying an aircraft on channel 35 (used for 72.490 MHz in North America), and someone else turns their radio on the same channel, the aircraft's control will be compromised and the result is almost always a crash. Since multiple RC frequency use began in the RC hobbies in the mid-20th century, so-called "frequency pins" have been used to ensure that only one modeler was using a particular frequency at any one time, for "traditional" style, crystal-controlled RC system use . The common, spring-loaded two-piece wood clothespin - marked in some manner with text and/or color-coding for the designated frequency it references, usually with an added piece of thin plywood or plastic on the clothespin to place the text or color-code upon for greater visibility - is the usual basis for these. Usually, the model club itself will possess some sort of "transmitter impound" facility at their modeling site for secure storage of the modelers' transmitters when not in active use while visiting the facility, and usually provides some sort of fixed "frequency control board" nearby to the impound area. The "frequency control board" at a modeling club's facility is used in one of two ways: either the club provides sets of frequency pins itself, already clipped onto the control board for the modeler to take the appropriate pin for their modeling activity (clipped onto their transmitter's antenna, in a so-called "subtractive" method) while their transmitter is in use away from the impound area, or with the modeler required to provide them for their own transmitter(s), and places them on a club facility's existing frequency board (the "additive" method) whenever they are using their RC transmitter.
   Section::::Types of kits and construction.
  
  There are various ways to construct and assemble an RC aeroplane. Various kits are available, requiring different amounts of assembly, different costs and varying levels of skill and experience.
   'Model' helicopters can be dangerous. Safety precautions, proper maintenance, and an understanding of the mechanics and flight characteristics of the models are necessary to prevent accidents. Modelers who fly at sanctioned sites are required to follow safety rules designated by national model aircraft organizations. In the United States, the Academy of Model Aeronautics (AMA) publishes and updates safety rules for all model aircraft operations, including fixed and rotary wing models. In 2014, several organizations with interest in unmanned aircraft systems in partnership with the Federal Aviation Administration launched a new educational campaign to promote safe and responsible flying and provide guidance for hobbyists and commercial users.
   Usually a single-chip 4017 decade counter is used inside the receiver to decode the transmitted multiplexed PPM signal to the individual "RC PWM" signals sent to each RC servo.
  
  Often a Signetics NE544 IC or a functionally equivalent chip is used inside the housing of low-cost RC servos as the motor controller—it decodes that servo control pulse train to a position, and drives the motor to that position.
   US Federal Aviation Administration regulations from 2006 grounding all commercial RC model and unmanned aerial vehicle (UAV) flights have been upgraded to require formal FAA certification before being permitted to fly at any altitude in the United States. All commercial owners must register with FAA, as well as pass a knowledge test. Non-commercial operators must register only if the models they fly weigh more than 0.55 pounds (250g).
  
  Section::::Safety.
   Some complex scale models use a fly-by-wire approach to allow a multitude of extra working features. A radio-control transmitter's encoder unit can be adapted, with no RF signal board present, to send its control signals along insulated control lines, instead of broadcasting them using radio frequencies. If signals are sent down the lines, the normal serial multiplexing of the control signals by such an adapted RC transmitter's encoder unit, solely sending those signals along the usual duo or trio of control lines, gets picked up by decoding gear in the model - usually adapted from an RC receiver, without an RF "front end" section - and permits many functions to be controlled without the use of additional lines. Standard servos can then be used in the model. From 2013, in the USA, the radio control "over the airwaves" of any moveable feature of control-line Scale or Carrier models (except the elevator) is permitted - this may spread to Europe and beyond in time.
   Hobby grade models can be fine tuned, unlike most toy grade models. For example, cars often allow toe-in, camber and caster angle adjustments, just like their real-life counterparts. All modern "computer" radios allow each function to be adjusted over several parameters for ease in setup and adjustment of the model. Many of these transmitters are capable of "mixing" several functions at once, which is required for some models.
   Several major manufacturers (including Märklin, Roco, Hornby and Bachmann), have entered the DCC market alongside makers which specialize in it (including Lenz, Digitrax, ESU, ZIMO, Kühn, Tams, North Coast Engineering (NCE), and CVP Products' EasyDCC, Sound Traxx, Lok Sound, Train Control Systems and ZTC). Most Selectrix central units are multi protocol units supporting DCC fully or partially (e.g. Rautenhaus, Stärz and MTTM).
  
  Section::::See also.
  
  BULLET::::- List of network buses
  
  Section::::External links.
  
  BULLET::::- NMRA Standards and Recommended Practices page
  
  BULLET::::- The NMRA's trademarked DCC logo
  
  BULLET::::- DCC History at the DCCWiki
  
  BULLET::::- The DCCWiki
  
  BULLET::::- Wiring for DCC
   Of much less complexity are the types of RC jet aircraft that actually use an electric motor-driven ducted fan instead to power the aircraft. So called "EDF" models can be of much smaller size, and only need the same electronic speed controller and rechargeable battery technology as propeller-driven RC electric powered aircraft use.
  
  Radio-controlled jet aircraft are produced in the colors of various airlines. Among the most popular airline liveries used by modelers are those of American, Singapore, Pan Am, Etihad and Delta Airlines.
  
  Section::::Types.:Sports planes.
   There are many other subsystems that together ensure proper operation, such as environmental control, transmitter, mount movement control, power control and distribution, and so on. It takes six to eight months to train a technician to maintain, operate, and repair the CIWS.
  
  Section::::Incidents.
  
  Section::::Incidents.:Drone exercise accidents.
   A modified RC10 with an off-the-shelf Parma International 1963 Chevrolet Corvette body was used in the famous chase scene in the 1988 motion picture, "The Dead Pool". In it, Clint Eastwood as Dirty Harry is being pursued through the streets of San Francisco, California by a highly explosive bomb disguised as an RC car. The "bomb" was actually driven by IFMAR world-champion race driver Jay Halsey. The car was in fact an electric; the sounds of a nitro-powered engine were added in post-production.
  
  Section::::New Ownership.
   The legal status of radio-controlled model aircraft under federal aviation law is currently unclear. In March 2014 in the case "Huerta v. Pirker", an administrative law judge with the National Transportation Safety Board (NTSB) dismissed an FAA enforcement action against a model aircraft operator under 14 CFR 91.13 (prohibiting careless and reckless operation of an aircraft), ruling that model aircraft are not legally classified as "aircraft" and that they are not subject to any current Federal Aviation Regulations (FARs). This decision was appealed to the full NTSB. In November 2014 the NTSB issued a ruling reversing the administrative law judge's decision and holding that model aircraft are legally considered "aircraft" at least for the purposes of 14 CFR 91.13, and remanded the case to the administrative judge to determine whether Pirker's actions constituted reckless operation. It remains unclear what other provisions of the Federal Aviation Regulations are applicable to model aircraft, but it is likely that every regulation applicable to "aircraft" generally would potentially apply under this standard.
   In recent years, the theme park industry has begun using AGVs for rides. One of the earliest AGV ride systems was for Epcot's Universe of Energy, opened in 1982. The ride used wired navigation to drive the 'Traveling Theatre' through the ride. Many rides use wired navigation, especially when employees must frequently walk over the ride path such as at (the now-closed attraction) The Great Movie Ride at Disney's Hollywood Studios. Another ride at Hollywood Studios that uses wired navigation is The Twilight Zone Tower of Terror, a combined drop tower/dark ride. The elevator cars are AGVs that lock into place inside separate vertical motion cab to move vertically. When it reaches a floor requiring horizontal movement, the AGV unlocks from the vertical cab and drives itself out of the elevator.
   Many toy R/C cars and wireless keyboards and mice operate on the 27 MHz R/C channels, especially 27.145 MHz. But most of these devices run far less than 4 watts and do not operate under the RCRS service. Instead, they operate under the FCC's Part 15 rules, which allow a wide variety of low powered devices to use the frequencies from 26.96 to 27.28 MHz, which covers CB Channels 1 through 27. Newer wireless keyboards and mice tend to use Bluetooth technology or frequencies in the 2.4 or 5.8 GHz region. Some R/C devices, especially quadcopters/drones, use cellular data techniques.
   The construction of helicopters has to be more precise than for fixed-wing model aircraft, because helicopters are susceptible to even the smallest of vibrations, which can cause problems when the helicopter is in flight.
   In the early 21st century, 2.4 gigahertz spread spectrum RC control systems have become increasingly utilized in control of model vehicles and aircraft. Now, these 2.4 GHz systems are being made by most radio manufacturers. These radio systems range in price from a couple thousand dollars, all the way down to under US$30 for some. Some manufacturers even offer conversion kits for older digital 72 MHz receivers and radios. As the emerging multitude of 2.4 GHz band spread spectrum RC systems usually use a "frequency-agile" mode of operations, like FHSS that do not stay on one set frequency any longer while in use, the older "exclusive use" provisions at model flying sites needed for VHF-band RC control systems's frequency control, for VHF-band RC systems that only used one set frequency unless serviced to change it, are not as mandatory as before.
   A microcontroller-based design would be appropriate where hundreds or thousands of units will be produced and so the development cost (design of power supplies, input/output hardware, and necessary testing and certification) can be spread over many sales, and where the end-user would not need to alter the control. Automotive applications are an example; millions of units are built each year, and very few end-users alter the programming of these controllers. However, some specialty vehicles such as transit buses economically use PLCs instead of custom-designed controls, because the volumes are low and the development cost would be uneconomical.
   Section::::Safety.:Deaths.
  
  In July 2013, a 41-year-old Swiss man was found dead in Mauensee near his model helicopter. He had "severe head and arm injuries".
  
  A September 2013 incident in New York City highlighted the possible dangers of remote controlled model helicopters when a 19-year-old enthusiast, who was very experienced in flying remote controlled helicopters, died after one of his helicopters' blades struck his head.
  
  Section::::Miniature helicopters.
  