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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.


Airborne RC Battery Indicators


What a brilliant idea... a little electronic gauge that will tell you just how much charge is left in the battery which powers your receiver and servos.

Hextronic battery indicator

Instead of guessing whether your battery has enough charge for one more flight, what if you could actually see how much capacity remains?

Even better, what if that gauge was able to be seen and read from a distance, so you could check now and then by doing a low-pass down the flight-line

Well that's the theory... what's the reality?

Perhaps the most common of these battery indicators is the smart little unit sold under a number of different brand-names and which consists of an array of bright LEDs, a switch to choose between 4.8V and 6.0V, and short lead to plug into your receiver.

When something like this is sold for under $4, I have to admit that I wasn't expecting too much, especially since other units carry a price of up to five times that amount.

Quality of construction

While the basic circuit-board is quite sound and reasonably well constructed, thanks to the use of subminiature surface-mounted components, the tiny switch on several of the units tested was intermittent - not good.

The units come with double-sided foam tape already affixed to the back surface making them easy to install on most models but difficult to remove once fitted.

The supplied lead is probably plenty-long enough for most installations and is fitted with a universal (JR/Hitec/Airtronics) connector that should fit any standard RC system.

How well does it work?

Obviously what you really want to know about this is whether it really can tell you how charged your batteries are.

I tested several units by applying a variable regulated voltage to the units and noting at what point the different LEDs illuminated.

Here's what I discovered...

6.0V  5.75V5.84V6.11V
4.8V  4.70V4.82V5.29V

So what does this mean?

Well it look as if the Hextronic/TowerPro battery indicator would be a fairly accurate indicator of most modern nicad or nickel-metal hydride battery packs.

What was a surprise however, is the fact that the low-green level for the 4.8V pack is still higher than the "nominal" voltage of 4.8V, whereas the low-green level for the 6V pack is actually well under 6V.

In practice, this may be a good thing, since a 5-cell pack has more reserve voltage headroom anyway so is less likely to produce a brownout or receiver reboot than a 4-cell one anyway.

The Verdict...

So are these things really worth the paltry amount the cost, or might they tempt you to have just one flight too many because you're still "in the green"?

test setup Based on the sample tested, it would seem that the "RED" voltage is still fairly conservatively high making it unlikely they'll over-estimate your remaining capacity.

However, the most effective way to be sure you're not going to run your batteries flat is to use a modern charger/cycler to measure the remaining capacity once the red LEDs start to glow.

Experience indicates that most of my 40-sized models consume anything from 80-140mAH per flight so I was pleased to see that the red light on one of my models actually left me enough for two safe flights because there was in fact some 350mAH remaining in the pack.

On their own, these devices aren't a guarantee against running out of battery power but they are an excellent reminder and a warning against some other problem that might cause your batteries to dip unexpectedly.

And besides, they look kind of cool, especially if you mount them inside a model's cockpit so they're visible through the windows.

Apart from the flaky switches, the Hextronic/TowerPro voltage indicator gets a thumbs-up from

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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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Review: iMax 9X 2.4GHz radio

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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!

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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?


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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