The new 2.4 GHz Spread Spectrum Radio is here! With this new technology, you no longer have to pin the frequency board, worry about off site interference form other radios or outside interference in the area, or concern yourself with shooting someone else down who might be flying in the area on your frequency. And, it’s safe to use in both air and surface vehicles. Now is that cool or what?
The reason is that this new technology does not operate on the 72MHz. The radio broadcasts on the 2.4 GHz band, and is designed to scan the frequency band until it finds an open channel, then locks the receiver onto that frequency. What’s even better is it does this twice, every time the radio is turned on, (it takes about 2 seconds) so that it broadcasts on 2 separate frequencies simultaneously so that if one sees interference, the other will cover until it passes. The Rx is actually 2 receivers in one.
To insure the radio will not talk to another radio of the same type within its range, the receiver is “bound” to the transmitter with a GUID (Global Unique Identification Number) so that the Rx will only recognize the transmitter it is bound to. With more than 4.2 billion GUID codes available, the chances of two radios operating on the same code is practically non existent. And for those who like fail safe, the radio can be programmed to shut the motor off if the signal is lost, and unlike the old systems that push the controls to the extremes when a glitch occurs, when the signal is lost, the Rx simply stops responding.
Sounds expensive, huh? Well here’s the good news, the 6 channel Tx with 10 model memory and 9.6 volt 600 mah NiCD battery with charger, Rx, and 4, 7.5 gram sub-micro servos has a street price of just $199.00. To me, that sounds like a bargain even on 72 MHz.
- Digital DSM (Spread Spectrum Modulation)
- 10 model memory
- Airplane and Helicopter functions
- Dual rates for aileron (rudder on a 3 ch. model) and elevator
- Exponential Rates for aileron (rudder on a 3 ch. model) and elevator
- Dual and Exponential rates can be combined on a single switch
- JR Radio-compatible trainer function
- Adjustable Control Stick lengths
- Throttle trim only effects idle position
- Two speed menu scrolling
- Throttle Smart Failsafe system
- Digital Trims
- 6 Channels
- Case Dimensions: 1 3/8” X 15/16” X 7/17”
- Weight: 7 gr. (I really like that!!!) Street price around $60.00 – no Xtl req.
- FrequencyRange: 2,400 – 2,485 MHz
- Antenna Length: 3.75” (2 antennas per Rx)
One of the main advantages to the new 2.4 GHz system is that the two Rx antennas are only 3.75” long each, so there won’t be any more long ugly antennas dangling from behind the model. And here’s even better news. Model airplanes generate radio “noise” that occurs from about 300MHz down. The 72MHz systems operate in the lower 1/3 of that noise spectrum, so it is possible to essentially “shoot yourself down”. Since the new Spread Spectrum system operates at over 2,400 MHz, it’s not susceptible to any of the noise generated by the model itself from rattling metal parts, motor or ESC noise.
Is there a down side to this new radio? Actually yes, but only one that I can see! The maximum recommended range is advertised at 2.000 feet, so the radio really isn’t well suited for larger models. But, for the small airplane and the competition Fun Fly Guys it’s just the ticket. For Park Flyers, small helicopters and medium sized electrics there’s just nothing better. If you think about it, if the range were really only 1,500 feet, do you think you could see a 40” span model out more than 1/4 mile anyway? I know I couldn’t!
OK, is this all just talk or what? No! I’ve been using my Spektrum now for about 3 weeks, and haven’t had a single problem. I tested it first in a “throw away” airplane – just in case. The first two flights totaled about 45 minute’s air time. The second test was in a boat. While the Guys on 75 MHz were out there twitchin’ and glitchin’ and shutting down, my boat ran smoothly and completely glitch free for an hour and forty-five minutes! Since then, I have flown it for over four hours air time in my 60” Cub and have not had a single problem. One thing I did notice when flying (or floating) the radio is that the Tx battery life is noticeably better then any other computer radio I’ve ever owned. I discovered later that the Tx power consumption is actually 40% lower then comparable 72 MHz radios, so that 600 mah battery is really equal to a 1,000 battery in the others.
As to programming, this radio programs just like any other JR radio of its type. I personally like JR, because when I got my first computer radio, JR offered the simplest and most intuitive programming method (as I saw it at the time). Since then, I’ve owned a 347, 783, 2, 622’s and a 652, and have not had any problems with any of them, and had no reason to anticipate any problems from this one either. I know it’s still early in the game, but after almost 5 hours of operation -- so far, so good. But to be perfectly honest, I do have one complaint! The Tx antenna is so short (6 1/2") that I can’t hang a “windsock” ribbon from it. Makes landing small light airplanes a much bigger challenge!
For more in depth information on the new Spread Spectrum system, pick up a copy of Back Yard Flyer (March 2006). The reviewer did some things with his radio that I would not even consider with mine, and is reported to have worked flawlessly throughout all of it! Also, there was a similar write up in the August 2005 Model Aviation. So if you’re into smaller models, and you’re in the market for a new radio, the new Spektrum is definitely worth giving a second look – I’m sure glad I did!