An Introduction to the Basic RC System
AN INTRODUCTION TO THE BASIC RC SYSTEM
In this section, we cover the individual components of a remote control (R/C) vehicle. We also inform you of the benefits and function of each part and how upgrading affects the performance. Remember to take these opinions in context as they are only opinions – we point you in the correct direction based on your racing goals. Please realize that everyone at Pacific Coast Hobbies is your friend as well as your racing partner. We are always completely neutral regarding our recommendations between brands. Our mission is to get you to where you want to be in your racing endeavors. Please feel free to contact us at any time, we’re happy to help.
This area has gone through a technological revolution over the past couple of years. Radio systems are considered the brain-works behind any type of RC vehicle, from land to air and sea. The radio system is one of the most important features that you can change. Today’s precise radio systems works on frequencies that transmit and receive the signals. Most radio systems can include the following: transmitter, receiver, one or two servos, on/off switch and other miscellaneous items. This is basically broken down into two types of systems.
The first is the atypical “crystal” type system. In order to change the frequencies, you have to manually pull out the crystal and insert/replace another crystal. This changes the frequency in which your system now transmits and receives. There are 2 different signal band ranges, 27 or 75 MHz. 27 MHz is what usually comes with Ready to Run vehicles, and 75 MHz is a nice upgrade with more frequency options. There are also 2 different airwaves, AM or FM. AM is usually more cost effective, while FM is a stronger signal.
The second is the Spread-Spectrum type 2.4 GHz system. This is the most convenient of all because it allows you to turn on the radio without checking frequencies against others. The 2.4 GHz systems can operate more than 80 different racers at once and can change its own frequency in the fraction of a millisecond – something that you won’t even feel or recognize. Most 2.4 GHz systems also have a built in fail safe feature, which is a great safety precaution.
Regarding the first system, it is necessary to check the frequency board at your local track before you can turn your transmitter on. The 2.4 GHz system allows you to turn it on without having to check the boards. The 2.4 GHz system operates on a completely different frequency and is the most advanced system currently available.
The bottom line is that you need to decide for yourself how serious and dedicated you will be to this hobby. If you are somewhat serious and will/might be racing every once in a while, we highly recommend a “high-end” radio system that can grow and be your racing partner throughout your R/C endeavors.
The heavy hitters in this industry are Futaba, Airtronics, and Spektrum. Of course, there are others, but these three manufacturers are huge in the industry. Compatible servos, receivers, and other accessories are easily available for these main brands, as well as great company backed customer service giving even more incentive to buy one of these big 3 brands.
Last, but not least, each brand has their flagship radio, the M11X for Airtronics, 4pk for Futaba, and the DX3R for Spektrum. Radios such as the Airtronics M11 and the Futaba 3PK are great in their own right and personal preference is the only determining factor when choosing between the two.
Recommended extras to purchase: extra receivers for multiple vehicles, rechargeable batteries for the transmitter, charger for the transmitter batteries, extra crystals for the conventional radio system.
THROTTLE AND STEERING SERVOS
Speed and holding power is translated into “speed and torque” in the servo world. However, when comparing, make sure that you compare the same voltage that the manufacturers are using when giving you the specs. The most common voltage rating to measure are either 4.6V-4.8V to 6.0V. Obviously the 6.0V readings will always be higher than the 4.6/4.8.
Also, you might not be aware, but gravity and off-camber turns and banks will really test the holding and strength of the steering servo. In 4WD applications, both on and off road, the inertia and torque of the front wheels will also play into the fact that you should have a strong, high-torque servo. When you step-up and get a high quality servo, you will IMMEDIATELY NOTICE and appreciate the difference.
Regarding the throttle servo, a self centering servo, to go back to neutral is extremely important. For a throttle servo, you want to ensure that the servo has two important elements; speed and enough torque to hold the brakes under extreme conditions. For specifics on this application, please check with our knowledgeable staff to guide you in the right direction.
For the steering servo, you would generally want a servo that is not only high-torque, but fast as well. For the 1/10 application, around 200oz/in of torque, and a speed between .06 and .12s would be ideal. For the 1/8 Buggy and Truggy racing classes you are looking for the highest torque available, atleast 250oz/in. Some of the newer servos even surpass 400oz/in of torque!
RECOMMENDED TUNING FOR THE ANALOG AND DIGITAL SERVOS:
ANALOG: In the steering application, turn the steering wheel all the way to the right. You should hear the servo go to the end and if pushed further, it sounds like the servo is stressing out toward the endpoints. Turn the end point adjustment down until you barely hear the strain go away, then increase the EPA two to three clicks more.
DIGITAL: In all fairness, servo straining will destroy and kill your servo – no questions, no negotiations. YouNEVER want to strain your digital servo by overloading it with unneeded stress and strain. When setting your EPA with the digital servos, make sure you don’t hear any type of strain at the maximum throw. This system check will ensure your digital works strong and lasts a long time.
When setting your EPA with the digital servos, make sure you don’t hear any type of strain at the maximum throw. This system check will ensure your digital works strong and lasts a long time.
LAST THOUGHTS ABOUT SERVOS AND OPERATION:
Ever try to run while someone is holding you back? This is the same thing that can happen to your servo if you are not careful. For example, after building your vehicle, check the operation of your steering system BEFORE hooking up your servo. Many times, a new car will have some type of binding in the bell cranks, ball ends or somewhere that will prevent the steering assembly from operating freely. CHECK AND FIX before engaging the servo. This simple check will allow the servo to work more freely. Check this same procedure with the RTR kits too. Disconnect the linkage of the servo to the bell cranks and check the steering if it is free.
Along with the steering, make sure nothing is binding or holding the servo back on the throttle position. Simple operation checks like these will ensure that you have optimal function and guarantees you get the maximum out of your system.
ELECTRONIC SPEED CONTROLLERS
There are two major types of R/C speed controllers and motors:
Brushed type motors/ESCs are the technology that has been around for years. It is the cheaper of the two types and comes with most of the RTR models. The motors will eventually need service, or replacement. The faster the motor, the sooner it will need replacing.
Brushless type motors/ESCs are the technology of the future. Just arriving within the last couple of years, brushless has quickly taken a strong hold on the market. A brushless motor will last a really long time, as there is really nothing to wear out. Because of the complex nature of the motors, it takes a more sophisticated ESC and thus the prices are a little higher for an initial setup. However, in the long run, brushless technology will yield a lower cost and superior performance.
It’s important that I name a few major manufacturers in the industry that have taken the speed controllers to unheard of levels in the RC world. LRP, Novak, and Castle Creations have really done their homework. They offer a vast array of different speed controllers that keep you running very strong and fast.
BEGINNERS: In the RTR kits, most manufacturers already supply your kit with a speed controller. Most of the speed controllers are brushed digital units and are decent in their operations. However, if you happen to get a kit with an analog speed controller, which will need a servo to operate the swing arm, you should consider getting a digital speed controller as soon as you possibly can.
Another thing that you should consider as a beginner is to get a speed controller with reverse. Now that being said, please realize that reverse is NOT allowed in sanctioned or club type racing. When you crash into something, you MUST wait for the turn-marshall to manually retrieve your car before you can resume your race. However, my suggestion on having reverse, is purely focused on having fun. When at practice, especially as a beginner, nothing is more frustrating then going down to the drivers stand to retrieve your car every time it gets stuck.
WATCH YOUR LIMITS
Have you ever heard of the saying, “buy cheap, buy twice”? Same thing goes with speed controllers. The speed controllers are very precise and are critically advanced in today’s world of electronics – however, they have limitations. Read them and understand what those limits are. Some speed controllers have a potential 15 turn motor limit, some have a 19 turn limit. The higher end models have either no limit or something like a 5-7 turn limit. If you are thinking about running modified racing (highly recommended), you will need a speed controller that can grow as your driving and racing progresses. Don’t short-change your racing future by getting a speed controller with limits. In order to practice fast lines in stock racing, I highly recommend that you practice with a modified motor. Going faster with modified motors will allow you to drive much better in stock. Be realistic with your goals and what you want to do. Again, contact our staff and we will steer you in the right direction every time.
MOTORS AND BATTERIES
MOTORS – Here is where we get into horsepower wars. Whether it comes to stock racing or modified racing, the first question we hear is: “HOW FAST WILL IT GO?” This is often complicated to answer, unless you just want to know the miles per hour of the ready to run kit.
For the sake of keeping this simple, call our staff on the subject of nitro engines. There are a vast number of nitro motors on the market and narrating the specifics on each of them is close to impossible. With nitro motors, keep the temperature in check when running and get all the fuel out of the system when you are finished running, will ensure proper operation and long engine life.
Electric racers have three basic levels of racing: stock spec, spec, and modified. The stock spec class will run either a 17.5 turn brushless motor, or a 27 turn brushed motor. This is the best class for beginning and the motors are more comfortable in speed. The spec or spec modified class is a 13.5 turn brushless motor, or a 19 turn brushed motor. The class is designed for people whom are ready to move out of the stock class, but not ready for the full blown modified speed. The top level class is the modified class. This class is open to just about any motor turn. The motors are too fast for most people to drive and control, so it is not the place for beginners.
There are also, the KV rated sensorless types of brushless motors. These do not quite have the smooth ‘feel’ of the sensored type motors, but also don’t have as many limits or regulations. Please keep in mind that to race in a club or sanctioned event, the motor must be approved by the US sanctioning body for RC, named ROAR.
Motor maintenance is a critical aspect of using “brushed-type” motors. Every 4-5 runs, it is important to clean your motor, possibly “cut the armature” and replace the brushes for maximum performance. If you’re just out there to run as many times as you can and not worry, just run it until it stops and don’t look back. If you are a bit more serious, it is essential to maintain your system.
THE BATTERIES – Another sector in RC that has many different options. There are basically two categories of batteries: Li-Po’s or NiCd/NiMH.
Li-Po batteries are the ‘new school’ technology. Li-Po is short for Lithium Polymer. The batteries are a soft cell type battery. Each cell is 3.7 volts, so the most common batteries are 7.4V or 11.1V. The batteries are about 20-30% more expensive than Ni-MH batteries, but are a better value as their life span (number of charge cycles) is at least double. The Li-Po’s are a little more specific about how they need to be charged, and require a Li-Po compatible charger. Li-Po batteries are definitely the way to go for the best performance, and anyone looking to go race. Please ask one of our team members for more specific details.
Ni-Cd and Ni-MH are very similar. The Ni-MH (Nickel Metal Hydride) cells are a little newer, but have 1.2V per cell just like the Ni-Cd (Nickel Cadmium) cells. These packs are usually built into 6 (7.2V) or 7 (8.4V) cell configurations. The 7.2V 6-cell pack is the standard for most r/c cars. These batteries perform well and generally cost much less than the Ni-MH batteries.
BATTERY CHARGER – There are many different battery chargers on the market. Once again depending on your specific dedication to this hobby, we will be able to decipher whether you require a high end charger or simply a charger that will do the job efficiently without any bells and whistles. Please ask ou r knowledgeable staff which type is best for you.
Finally, get rid of that weak link. Often times, if your kit is a ready to run kit, you will want to get rid of the battery connector ASAP to get the most out of your electrical system. There are a number of different manufacturers out there that offer good battery plugs, but remember the plugs are a type of potential resistance. Any resistance along the electrical circuit will rob you of performance. The answer? Deans, E-Flite, and Traxxas all make a great plugs, and they have almost zero in resistance. Call our shop and we’ll hook you up with the right product.
TOOLS – Last, but NOT least, are the tools involved with this hobby. There are many different manufacturers of Allen (hex) wrenches and sockets, along with scissors, screwdrivers, calipers, etc., to add to your tool box. My personal suggestion is to have a complete set of tools and an engraver to customize your good set by engraving your name on them. A good set of tools will last you a long time and make working on you R/C cars much easier, and much more fun. So getting the best tools possible, will definitely benefit you in the long run.
In the world of remote control, there are many different things to consider, making it difficult to even know where to begin. We at Pacific Coast Hobbies will be there for you, from the starting line to the victory circle. What differentiates us from the other guys? We care and our prices are as good as our competitors, if not better. We have staff members and store friends that are National Championship caliber drivers, so we know the latest and greatest products, as well as all the pro tips and tricks. We are committed to our customers and focused on guiding your RC goals so that together we can make them a reality. Give us a try and we will show you how easy it is to go fast with a remote control.