So who's doing this reviewing then?
Well I've been building and flying or driving radio controlled models for over 40 years and during that time I like to think I've built up a reasonable amount of knowledge.
I'm also a qualified electronics engineer who has worked in radio frequency, analog, digital systems and software for more than three decades. In fact I designed and built my first RC set back in 1969.
For the past nine years I've also been involved in the design and manufacture of some rather sophisticated engine technology and UAV flight control systems.
So, chances are I've been there, done that and have a huge pile of tee shirts to prove it.
Right now I'm heavily into 3D flying and enjoy all aspects of the RC hobby. I may be old but I don't feel it.
In the Pipeline
Here's just a little bit of what's to come on this site...
RC explained: Demystifying terms such as PCM, PPM dual conversion, single conversion, full-range etc., this feature will explain it all.
Cheap Chinese Engines: Just how good are those cheap Chinese glow and gas engines that sell for half the price of their "brand-name" equivalent? I put several to the test.
Build your own radio gear?: Back in the old days, building your own RC gear was not uncommon and now the arrival of 2.4GHz has made it practical again.
2.4GHz R/C Shootout Results
SO WHICH IS THE BEST 2.4GHZ SYSTEM?
Dated: 6 May 2010
Over the months I've reviewed a good number of the 2.4GHz RC systems and modules currently on the market but there's one question I keep being asked:
"Which is the *best* 2.4GHz system?"
Well I guess I can only speak of those which I've either been able to afford to purchase for testing or whose manufacturers have been kind enough to donate a test sample but here is a summary of my findings...
Note: all the individual system reviews can be found here
Construction Quality and QC
As was to be expected, the "brand name" products generally showed a better quality of construction than the cheaper Chinese offerings. In fact, it's very clear that some of the Sino 2.4 modules/receivers are pretty much hand-assembled, perhaps on a kitchen table somewhere in the provinces -- I don't know.
Hitec's Spectra/Optima AFHSS system scored very well here and it was hard to find fault with the actual construction, although I was none too pleased with the fragility of their BODA receiver antennas, nor the draping cable to the antenna on the transmitter module.
The JR/Spektrum build quality was also good, and the only Chinese products really rivaling the name-brands were WFly and Assan, although Assan gets points off for its poor transmitter module antenna setup.
In the middle of the pack were the FlyDream and FrSky offerings, both of which seemed "adequate" in their build-quality but a rung lower on the ladder. There have been issues with the fit of the modules in various transmitters with these brands and I have ended up with a dud FlyDream receiver -- that's another reason they're not in the same league as Hitec or JR/Spektrum.
Of the Chinese manufacturers, I'd have to rate Corona down the ladder a bit more, having encountered a couple of "dud" receivers and a DIY kit with a faulty coax termination.
Right at the bottom would be the FlySky/HobbyKing product. Their 9-channel receiver is pretty awful when it comes to construction -- and early examples even had large capacitors supported only by their leads. This is something that would have lead to failure in aircraft with any amount of vibration.
The winners here are Hitec and JR/Spektrum which both showed that buying a "brand name" product can result in a little more peace of mind when it comes to quality of construction and quality control.
I'm pleased to say that all the products tested had far more range than anyone could possibly need, unless you're into long-distance FPV flying.
Three systems that looked as if they'd offer some small benefits in the range stakes were the JR/Spektrum, the FrSky and the WFly -- mainly because they offered true antenna or receiver diversity so as to ensure maximum range at all orientations. The Optima 9 receiver from Hitec would likely fall into the same category but I didn't have one to test.
The least range was provided by the FlySky/HobbyKing product (which is also the cheapest), while all the others offered far more than the 1Km of runway I have here on which to test them at ground-level.
Everyone is a winner in this category because they all the systems tested offer more than enough range to do the job.
Most of the systems tested were surprisingly resistant to interference, both from other RC systems, WiFi and nasty non-digital sources such as video transmitters.
The FlySky/HobbyKing and Assan I tested were only single-frequency systems and were the first to fail when the level of interference was raised on the part of the band they were using.
The Spektrum/JR was reasonably resistant to interference, so long as you didn't catch it when it had placed both of its transmitting channels too close together, in which case it faired no better than the Assan.
The next most resilient were the 3-frequency DSSS systems from WFly and FlyDream. At this level, it's pretty hard to imagine any "real world" situation where these systems could be knocked out because in each case, only one of the transmitting channels had to be free for continued operation. I did notice some occasional "odd" behavior from the Corona and the FlyDream did have a lower output than the others but I'd venture to say that they're all acceptable.
Moving up the ladder another rung is the FrSky. Its full-time frequency hopping uses all the band and even when I obliterated all but about 10% of the band, it still worked -- albeit quite a bit slower and more jerkily than normally.
Sometimes better than, sometimes worse than the FrSky was the Hitec AFHSS system.
If you took the time to use the scan mode to force the Spectra to adapt to the noise that was present on the band, the Hitec would work more smoothly and with less hesitation than the FrSky system but it was a bit of a crap-shoot as to which was actually better overall.
Suffice to say that both are pretty much bulletproof and you'd have to be flying in an incredibly hostile environment before you started getting hit with either of these systems.
The winners here are the Hitec and FrSky.
Most of the systems tested claimed to offer a 10-bit (1024 step) resolution, although the WFly and Hitec both offered more, and it showed.
It's an unfortunate side-effect of converting a PPM signal into digital then back to PPM (as all these module-based systems must do) that the transmitter's effective resolution can be reduced and that manifests itself as slightly less smooth servo movement and a small reduction in accuracy.
With none of the systems tested was this an issue of any significance, but the Hitec and WFly systems really showed the benefits that higher resolution can offer.
Having said that, I fly 3D with models which have +/- 50 degrees of throw on huge elevators, rudders and ailerons. At no stage, when testing any of the module/receiver combos, did I find the small lack of precision to be an issue although I'm sure I could feel the difference between the best and the worst.
The winners here are the Hitec and WFly with all others pretty much even.
Firstly, the clear loser here, and by quite a large margin, was the JR/Spektrum.
All the Chinese-made systems showed very good low-voltage performance and fast relink times. So long as you have half-decent batteries or BECs then brownouts or resets should not be an issue.
The Hitec has a fairly high brownout voltage too, and would have scored down near the bottom of the list if it weren't for the SPC (supplementary power connector) which allows you to run the receiver itself from a completely separate battery to the one which supplies the servos. This means that a small 2S lipo can keep your receiver running all day without fear of brownout, despite the relatively high reboot voltage.
There is another potential issue with the Hitec and that's when you use the scan mode. If you do encounter a bad brownout and resulting reset, the system simply will not rebind at all. See that SPC? Use it, if you fly in scan-mode!
The winner here? Well it's too hard to choose, the difference between the best and worst of the Chinese systems was so small as to be largely within the margin of error.
You'd think an easy to set, persistent failsafe would be standard equipment on all 2.4GHz receivers these days don't you?
Unfortunately it's not.
The Corona DSSS system offers a rather limited failsafe which must be re-set every time the receiver is turned off and the Assan system I looked at was also cumbersome and had to be reset every power cycle. I gather some of the more expensive Assan receivers are much improved in this regard but I could only report on the system I tested.
The FlySky/HobbyKing offers no useful failsafe capability at all, but it's also the cheapest.
All the others offered user-definable, persistent failsafe capabilities that worked well. It would have been nice if the failsafe settings could be set without having to press a button on the receiver (how about a button on the transmitter module?) but they all worked well.
Another feature I'd like to have seen more often is the power-down range-test facility.
FrSky, FlyDream, JR/Spektrum, and Hitec all offer this facility. With the range of these systems exceeding 1Km on the ground, there's no practical way to perform a sensible range test without this power-down capability.
Another nice new feature is telemetry and, of the systems tested, only the Hitec offered this. I have looked at a pre-release version of the FrSky system that also offers telemetry with the bonus that it is "open", allowing anyone with the skills and knowledge to develop their own add-ons. There are rumors that Spektrum will be releasing a telemetry-enabled system sometime soon but I've not seen nor tested it so can't include that in formulating my results.
The clear loser in the "features' category is the FlySky/HobbyKing, lacking both power-down range-test and any useful failsafe.
The winners here are Hitec and FrSky, because they tick all the boxes.
The hands-down winner has to be the FlySky/HobbyKing system. With receivers costing under $15 and the transmitter module costing (when it was available) about the same from HobbyKing (now nearly twice that from other sources) it represents the very cheapest 2.4GHz system.
Also near the bottom of the price-list but offering far more features and much greater performance is the Fly-Dream.
If you want an FrSky, Corona or WFly system you'll have to spend a little more and the Assan is more again.
For a brand-name system, the Hitec Spectra/Optima system is surprisingly affordable too, leaving the JR/Spektrum offering as the most expensive system tested to date.
And the BEST system is...
Well, to be honest, there is no "best".
If you expected me to give you an outright clear winner that would be the "best" system for every, you will be disappointed but that's only because everyone's priorities and needs are different. In other words, one person's "best" might be another's "not quite so good".
So here's how I see the results.
Tied for first place, purely on a performance basis are the Hitec Spectra/Optima AFHSS system and the FrSky module/receivers.
Performance and feature-wise they are very, very close -- both offering incredible resistance to all the interference I could throw at them.
If money was no object then the Hitec may just be the preferred option of many, since it comes with a "brand name" and, in the USA at least, legendary after-sales support.
Those who aren't interested in brand-names or who are happy to make do with lesser levels of support in return for a more than 50% price savings will find the FrSky offers virtually the same performance and features while being much easier on the wallet.
Both (will soon) offer telemetry and both have receivers available that provide true antenna diversity.
The FrSky has better low-voltage performance -- but the Hitec has its SPC to cover that weakness. The Hitec has its fragile BODA antenna and unprofessional-looking external antenna cable at the transmitter end but the FrSky has issues with the fit of its transmitter module in some radios. Hitec has higher resolution, FrSky has lower prices.
This is really a case of swings and roundabouts.
For me, the FrSky is the winner but that's solely because it costs just half as much as the Hitec system. If money were no object then I'd be just as inclined to go with the Hitec but unfortunately, like most people, I have to work within a budget and going with FrSky means I can afford to buy twice as many receivers for my dollar without sacrificing anything significant (to me).
To prove that I am prepared to put my money where my mouth is, I've been flying almost all my own models (jets, trainers, 3D aerobatic planes, warbirds and others) on the FrSky system for several months now and am glad to report that I've not had a single issue -- other than those associated with the fit of the transmitter modules I've already mentioned. I would not have dared to recommend a Chinese-made RC system without having risked all my own models to it for a goodly length of time, and I have.
Having said that, all the systems reviewed have passed the flight-tests and will, in most situations, represent perfectly adequate ways to convert your existing module-based radio to 2.4GHz operation. Each has its own pro's and con's. For example, if price is your bottom-line then the FlyDream product starts to look pretty good. It offers better performance than the Spektrum system at a fraction the price and that savings can make a real difference when you're on a budget.
Now I'm sure that some readers will have noticed an important brand missing from my tests: Futaba.
Based on informal testing (because I've only had very limited access to FASST-based systems borrowed from others) it would appear that Futaba's system is rock-solid and very good in all respects, except price. If Futaba want to make a system available for testing I'll gladly add it to the list of reviews. However, the "brand name" vendors (Hitec excepted) seem very reluctant to have their systems really subjected to honest review by RCModelReviews.com. I'll leave it up to the reader to work out why that might be.
Ultimately, the real winner in the move to 2.4GHz is you -- the RC model flier. That's because there's never been more choice, better products and better prices.
Updated: 20 Sep 2012
Here's a blog that will keep you informed just what's going on behind the scenes at RC Model Reviews and also tells you a little more about myself.
23 Mar 2010
How come there's no compatibility between different brands of transmitters and receivers? Why can't you use a cheap Chinese receiver with your Futaba FASST radio?
4 Mar 2010
Since this has become a very frequently asked question, I've posted this simple guide to getting your product, or a product you're thinking of buying reviewed here at RCModelReviews
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