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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.

 

How do FHSS RC systems work?

FREQUENCY HOPPING SPREAD SPECTRUM

Futaba transmitter

Frequency Hopping Spread Spectrum radio systems work by constantly hopping between a number of frequencies.

If you've just read the description of how DSSS systems work you're probably wondering "what's the difference?"

Well, whereas the DSSS system is like a car that repeatedly appears and disappears on various lanes of a freeway, at such a rate that it almost appears to be everywhere at once, a FHSS system effectively sees your car not simply jumping a small distance to a nearby lane, but all the way to a completely new freeway.

In radio terms, this means that the frequency sent by the transmitter doesn't just jump around within the chosen operating channel but actually jumps between a whole range of different channels.

It can be seen that, at least in theory, the FHSS system should be even more immune to the type of congestion that would cause problems with a DSSS system. That's because although nothing may get through while it was using a very congested freeway, the hop to a less congested one would allow the normal transfer of data to resume.

Under normal circumstances a FHSS system hops between a fixed number of channels in a repeating random sequence. When multiple FHSS systems are used together, the random anture of the hopping sequence means it's very unlikely you'll find multiple sets trying to use the same channel (freeway) at the same time.

How FHSSS Handles Interference

THE BATTLEFIELD ANALOGY

In a pure FHSS system, the troops are all closely grouped together as was the case with an old narrowband system but, because they're constantly jumping from battle-field to battle-field, the effect of enemy fire in any particular field is minimal.

Imagine that the whole army is teleported onto a battle-field and then, before you realise it, telported away to another. Clearly this makes a FHSS system a hard target for interference to hit.

However, the FHSS systems we're seeing used in radio control systems right now are a blend of both DSSS and FHSS. This means that not only is the signal spread across a whole channel but it also hops continuously from one channel to another.

This means that an FHSS system is an incredibly difficult target for any interference to hit -- and when you're flying RC models, that's a very good thing.

Which radios use FHSS

Right now, only two readily available 2.4GHz spread spectrum radio control systems use FHSS. These are the FASST radios from Futaba and the Airtronics offerings.

Next Page: The belt and braces approach

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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

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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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