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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.

 

Nickel Metal Hydride (NiMH) batteries

CHEAP, RELIABLE AND EFFECTIVE

Nickel Metal Hydride (NiMH) batteries have largely taken over from nicads in the area of transmitter and receiver packs.

Although early NiMH cells were sometimes problematic and not well suited to applications such as RC systems, today's versions are far advanced and represent the most practical solution for many applications.

Just about the only problem I've found with NiMH batteries is that many of those made in China simply don't have the claimed capacity and can therefore leave users wondering why they're not holding a proper charge.

NiMH Pro's:

  • high capacities possible (AA cells of up to 2700mAH)
  • no memory/voltage-depression effects
  • less of an environmental problem than nicads
NiMH Con's:
  • can self-discharge more rapidly than other technologies
  • hi-capacity batteries can be delicate and unsuited to receiver packs
  • not always the advertised capacity

The essential forming charge

Whereas nicad cells can be used straight out of the box, NiMH packs require a "forming charge" if you're ever going to see their maximum capacity realized.

This forming charge must be done at no more than the 10-hour charge rate (1/10C) and ensures that the plates inside the cells are properly conditioned for use.

You should not use a peak-detecting "smart" charger for this forming charge as it will almost certainly either false-peak or fail to detect when the battery is fully charged. It's best to just use the wall-wart charger that came with your radio and calculate how many hours will be required to pump 120% of the cell's rated capacity into the battery.

For example, if your wall-wart charges at 50mA and you're trying to form-charge a 1500mAH battery then you need to leave it on for (1500/50) x 1.2 which is 36 hours.

Always keep an eye on a new battery that's being form-charged to make sure it doesn't get warm. If it does then it's taken a full charge (it was proabably half-charged to start with).

When to use

Right now, NiMH batteries are about the best choice for transmitter packs and receiver packs in many models.

Caution must be observed when using hi-capacity NiMH cells (over 1650mAH in AA size) because these are more easily damaged by over-charging or charging at too high a current. I prefer to stick with a good quality 1650mAH transmitter pack and top them up at the field if needed (charging at up to 1.0A).

While the higher capacity NiMH cells (up to 2700mAH in AA size) might seem to be better, they will self-discharge more quickly when the gear is turned off and can only be charged at currents of about 250mAH -- making field-top-ups impractical.

And don't be tempted to use the hi-capacity AA cells for receiver packs on anything larger than a .40-sized sports model. The price you pay for this higher capacity is a decided tendency for the voltage to drop under load. There's always a risk that if the voltage drops enough, your receiver will stop working and you could lose control of the model (particularly true with 2.4GHz radio systems).

A favorite NiMH receiver pack of mine is the 2/3A-sized Intellect cells with 1400 mAH capacity. These cells can deliver up to 20A continuously and I've flown my 30% Extra using two of these packs without problems. They weigh about the same as an AA-sized pack but are much better.

Next: Lithium Polymer batteries (LiPo)
Back: Nickel Cadmium batteries (nicad)

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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

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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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