RC controls systems have changed a lot over the last few years, especially since the 2.4GHz systems started to appear. As with a lot of electronics, especially in the RC field, prices have come down significantly. This in of itself has helped open the hobby to more people across the world.
While a lot of the technology has changed that makes the systems go, the hardware looks and operates much the same. A couple of things to note: The size and weight of the receiver has decreased significantly, while surprisingly, the transmitters are about the same size as they were 30 years ago.
Most RC systems you buy will include:
Some systems come with servos, but it seems because the variety of uses and applications have widened, less and less systems come bundled this way any more.
Depending on what type of RC boat you're building, here are some other components you may need to complete the control system:
Most Radios are made and marketed toward either the RC plane or RC car/buggy markets. To my knowledge there are no optimized RC systems strictly for boats.
As a result the transmitters you'll find are either Pistol Grip - developed for RC cars, or Stick generally intended for RC planes.
It seems, maybe not too surprising, that pistol grip radios are favored by those running high speed boats such as hydros, tunnel hulls, mono-hulls.
Stick radios are often seen as more universal. If you need multiple functions - say four or more, you're not likely to find it on a pistol grip. Stick radios are often favored by those who have had exposure to RC helicopters, airplanes and RC robotics.
Which one is "better" for RC boats is entirely a matter of taste. Use whatever you feel more comfortable with. Generally, if you are more interested in RC cars than planes, let that be a clue as to what to try first and vice versa, of course.
I don't like pistol grips. I'm not knocking it - these systems work great for a lot of people. I'm a south-paw (left handed for my non-US visitors), so I could never get my hands to do what I wanted them to with a pistol grip - it was very frustrating. I may have tried harder if I hadn't been "brought up" with stick radios.
Before I got my Tactic TTX-404, my previous systems were purchased for the dual purpose of air/ground. At the time I still thought I'd be able to learn how to fly RC planes. I gave up that idea 20 years ago.
Today things have changed. If you are looking for a dual purpose air/ground radio, the 2.4GHz Spread Spectrum systems is pretty much it. The 72MHz band is dedicated to Aircraft and the 75MHz to Ground. Don't violate these FCC rules, they can confiscate your equipment - model and all.
For buying new I would only consider a 2.4GHz Spread Spectrum system. It's simply ingenious the way it's designed.
There are 100 frequencies within the 2.4GHz band and shared with anything from remote car door openers to cordless phones.
Here are a few notes about the 2.4GHz Spread Spectrum:
If I were considering a used system, I'd look for a Brand-name Spread Spectrum or ditto 75MHz radio on ebay.
I'd be hesitant to buy:
OK, don't laugh, but a number of tinkerers have had great success stripping the RC controls from toy trucks. This is an economical option if you're on a tight budget and will operate within a limited range. I would expect the range to be around 100ft, possibly even less.
Personally, I would not buy new or used AM or FM gear. I have a feeling we're just entering the 2.4GHz Spread Spectrum era in RC controls. I would not be surprised if prices on brand name systems will come down in the next year or two.
For RC boaters a lot of high-end radios are loaded with mixing functions you don't need, or plainly can't use. If you're looking for dual purpose Air/Ground - by all means - it's a whole other story and the sky is the limit.
For RC boats, I'd look for a relatively basic 2.4GHz Channel Hopping system. That pretty much excludes the low-end such as many Hobby King radios around $25.
There are other brands though. The Spectrum DX5e for instance will cost you $80 for Transmitter and Receiver and I've heard good things about them. Here are a few more to consider:
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