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Your Reviewer

My Credentials
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.

 

The 2.4GHz Spread Spectrum FAQ

QUESTIONS AND ANSWERS TO THE 2.4GHZ PUZZLE

spectrum analysis

Do you have a question about Spread Spectrum 2.4GHz radio systems?

If your question isn't already here, use the feedback page to drop me a line and I'll do my best to come up with an answer

Q. Is it true that you can't be shot down on 2.4GHz?

A. It is true that you can't be shot down by another 2.4GHz radio control system but there is still always a chance that other forms of interference can cause you to lose control of your model. The 2.4GHz band is used by a very wide range of other electronic equipment from wireless internet to microwave ovens. There's no guarantee that one of these other devices won't interfere with your RC set.

Q. Are there disadvantages to a module-based 2.4GHz system?

A. There are some disadvantages to using a module based system over a totally 2.4Ghz one. The newer non-module-based 2.4GHz systems often offer higher resolution and faster response. The JR native 2.4GHz systems also offer a unique feature (Model Match) that elminates the risk of flying with the wrong model memory selected in your transmitter.

Q. Can I use my existing servos with a new 2.4GHz system?

A. Yes, all of the currently available 2.4GHz systems are compatible with conventional (analog or digital) servos. There is talk of a new generation of totally digital servos becoming available specifically for advanced SS RC gear but nothing has yet been seen. The only exception to this is that some Hitec digital servos may not work reliably (or at all) with some Futaba FASST receivers due a lower than expected voltage on the signal line.

Q. What causes lockouts on 2.4GHz?

A. Spread spectrum radio sets work in a way very similar to PCM ones in the way they respond to strong interference. If you're unlucky enough to experience interference so strong that the link between transmitter and reciever is lost, your receiver will enter "hold/lockout" mode and then go to failsafe mode (if set).

The cause of such a lockout/failsafe can be almost anything including, but not just limited to, interference. In fact, in the case of spread spectrum systems, experience has shown that lockouts are far more likely to be caused by inadequate batteries in the model or bad installation.

Q. Should I switch to 2.4GHz now or wait?

A. this depends very much on your own situation. If you've never had a glitch with your existing narrowband RC system and have no problems with frequency control at your flying field then there's no reason why you should rush out and by a 2.4GHz spread spectrum set. However, if you do live in an area where interference on your existing set is not uncommon, or if there are long queues for frequency pegs then the move might be worthwhile.

If you're just starting out in the hobby and don't yet have any RC gear then it probably makes sense to go straight to 2.4GHz.

Q. Why are good receiver batteries so important on 2.4GHz? A. Inside every spread spectrum receiver are an array of tiny computer chips that must perform millions of complex instructions without mistakes every second. In order to function reliably, these computer chips require a steady stream of electricity. If that steady stream is interrupted, even for a tiny fraction of a second, the computers can crash or stop working briefly.

This means that if your receiver batteries, BEC or regulator aren't up to scratch then you will almost certainly have real problems with your new 2.4GHz radio.

Unless you're flying helicopters with servos that can't handle the extra voltage, it is strongly recommended that you use a 5-cell receiver pack (6V) or even one of the new 2-cell A123 battery packs (6.4V) to further reduce the risk of voltage-related receiver problems.

Many of today's hi-torque servos can draw very high amounts of current and if your battery isn't up to the task, this can cause the voltage they deliver to be drastically reduced. Should that voltage drop below the 4.5V some receivers require to function, a lockout or reboot may result. Remember that when the computer in your 2.4GHz recevier crashes, its' quite likely your plane will also crash. Good batteries of adequate capacity and well-charged are absolutely essential to safe flight.

Q. Can I use a 2.4Ghz system in my carbon fiber glider

A. Unfortuately carbon fiber acts as a pretty good shield against 2.4GHz radio transmissions. This means that if you mount a 2.4GHz receiver inside a carbon-fiber fuselage, it probably won't work very well at all. For this reason, many glider fliers (especially DLG fliers) are sticking with narrowband radios where not only are the frequencies less affected by carbon fiber but at least some of the antenna can be routed outside the fuselage.

Some 2.4GHz receivers such as those from Futaba have extended antennas that make it easier to route them through the CF to the outside world. It's still very important to make sure that at least one antenna is visible from every angle.

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The Blog

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.

How compatible are 2.4GHz RC systems?

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?

How to get a product reviewed here

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

How servos work

Useful information on what's inside your servos and how they work.

The Good Oil

Important facts you should know about the oils that are used in our model engine fuels.

Heads-Up: 2.4GHz RC systems tested

How well do five different 2.4GHz systems stack up when hit by interference? The answers are here, with more to come.

Review: Bushnell's $80 Speed Gun

Yes it does work on model airplanes but there are some limitations involved with this bargain-basement radar speed gun.

Review: TowerPro MG995 servo

These are possibly the world's worst servos, find out exactly why you should avoid these boat-anchors at any cost.

Review: SK90

2.4GHz

It's cheap but can it really stack up against other glow engines in the .90 market? Find out in this review.

Review: iMax 9X 2.4GHz radio

How does this cheap 9-channel 2.4GHz radio system perform when compared to big-name systems that can cost two or three times as much? Have the Chinese finally developed a real contender with the iMax 9X?

2.4GHz Explained

Does all this 2.4GHz stuff have your head spinning? 2.4GHz

I've done my best to demystify the whole subject so if you feel like a bit of learning, this is the stuff for you!

Fix That Engine!

How can you tell when your engine needs new bearings? Who has the best prices and service on replacements? Just how do you change them? Get all that information and watch a great video tutorial anyone can follow.

Chinese Servos - How do they stack up?

Servos

The Chinese are now churning out a huge number of very reasonably priced no-name servos. But are they any good?

Baffled by batteries?

Batteries Nicad, NiMH, Li-Ion, LiPoly, LiFePO4, A123... the range of different battery types has never been greater. So how do they differ and what type should you be using?

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