DSM, or Digital Spectrum Modulation, is a radio technology which has become an important improvement in the world of RC cars, helicopters, airplanes or trucks. This technology answers to a specific need of RC cars enthusiasts, as more and more of them have reported that radio interference is impeding good competition, especially when multiple players are controlling cars and planes at once.
How does this technology differ from the traditional radio system? The regular radio system on RC car incorporates a receiver and a transmitter that each contains a crystal, which is set on a specific frequency band and channel. This can cause interference, especially if two RC cars are using the same type of crystal and they are turned on. The DSM controllers and receivers do not pose this problem, as they work in a slightly different way than traditional radio systems.
Basically, DSM technology aims to eliminate the problem of radio interferences by having the user’s controller emit a narrow band signal that changes from one frequency to another within split seconds. This optimized digital communication technology is completely crystal-free and is not affected by cross-interference with regular radio frequency transmitters and receivers.
There are two subsets of DSM technology which are currently implemented. The first one is called Frequency Hopping Spread Spectrum and it works like it was said above, by bouncing from one frequency to another within milliseconds. This system was first used and it was helpful, even though some limitations were observed, which didn’t make it too reliable. The other method of DSM is called Direct Sequence Spread Spectrum, or DSSS, and uses only a single frequency, but on a very wide band. Only a small portion is used to transmit special encoded data to the transmitter and receiver.
This technology is especially suited to all RC vehicles, but it is most useful for RC car enthusiasts, which race in large competitions with lots of vehicles, as frequency interference can become a major issue. But, DSM technology is great for everybody! You won’t see your RC car hijacked by another transmitter on the race track and it won’t be acting erratically.
But what if you already have an RC car or other vehicles with a traditional radio system? There are certain modules which you can to buy adapt a traditional radio system to the DSM technology. The DSM controller has a receiver which is installed in line with the traditional radio receiver. That way, the DSM controller can communicate through the receiver to the rest of your RC car’s electronic components. Also, if you’re looking to buy a new RC car, there are several ready-to-race cars which already have DSM radio systems.
How do you use it? Before actually attacking the race track with your RC car’s new radio system, you should follow a few basic installation steps in order for your controller to lock onto the receiver. This is called binding and your DSM receiver has to search and recognize the DSM transmitter’s GUID code to lock onto it. Once this operation is successful, special software should be installed to help prevent the interference of frequency channels. This piece of software is installed on both the transmitter and receiver. This program will help you set the proper frequency.
This DSM technology has also other features. They tell you how much runtime your battery pack has left or they can time your laps. Basically, this new way of controlling your car ensures its protection against hijacking and also helps you optimize its performance with all the extra available options.