>Review: Corona 2.4GHz DSSS module/receiver

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.

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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.

Review: Corona 2.4GHz DSSS module and receiver

AT LAST, A HOME RUN FOR CORONA

Update: 26 September 2009
Right now I'm investigating some reports of issues with some of the Corona DSS systems that have been used in the field.

Although the system tested here did perform very well and there are plenty of folks who've had the same near-perfect experiences with the Corona DSSS, there are others who claim to have encountered problems with establishing a link between transmitter and receiver or getting glitches.

This may be down to any number of factors -- perhaps (again) quality control issues with Corona products or it may be installation/environment-realated.

As a result - I've ordered some more Corona equipment, purchased from an online dealer rather than being supplied directly by Corona. When this equipment arrives I will repeat my tests and see if there are any differences.

I will also be investigating how installatin/environment may adversely affect the performance of this equipment.

If you're already using the system without issues, don't worry. If you're thinking of buying, you might want to hang on until I perform some more testing on the new units due to arrive next week.

When I tested the Corona FHSS 2.4GHz module/receivers a couple of months ago, I was not impressed.

A number of problems were apparent with the FHSS system and some of those were serious enough for Corona to apparently go back to the drawing board. Hobby City, who'd been reselling the product under its in-house Turnigy brand, removed the modules and receivers from its site and opted instead to promote the FlySky ones, rebranded as HobbyKing.

I gave Corona full marks for responding to the weaknesses found in their FHSS system and was eager to see if their DSSS version was any better.

Clearly Corona thought it was, and sent me a system to cast a critical eye over. Here's what I found.

First Look

Physically, the Corona DSSS transmitter module looks the same as their FHSS one (same plastic) and in the case of the JR version, it still has the two holes on the top surface, one of which is used to mount the transmitter antenna. This is a legacy of early versions from Corona which actually used two transmitter antennas.

The 6 and 8-channel DSSS receivers come in the same hard-plastic case as the FHSS ones but I also received one of their really small and light 4-channel units.

Binding the receivers to the transmitter was a piece of cake. The "bind" button on the transmitter module is held down while the transmitter switch is turned on and then released. Then the bind button on the receiver is held down while its power is turned on.

A few flashes of the onboard LED later -- it was bound, although the servos don't respond to the tramsmitter sticks until both parts are turned on and off again.

What surprised me a lot was the long delay between turning on the transmitter and the servos responding. This power-up delay also occurs with the FHSS system but I don't see it being an issue. As with the FHSS system, it seems you should power up the receiver before the transmitter.

Once bound and linked, the servos followed stick movements smoothly and with none of the jerkiness seen in the FHSS product or the FlyDream FHSS system recently reviewed.

No complaints there -- one of the FHSS systems big deficiencies is clearly not present in the DSSS version.

The Receivers

Both the 6 and 8-channel receivers have two antennas that should be positioned at right-angles for best results. The 4-channel receiver only has a single antenna but that's probably never going to be an issue, given that it's clearly designed for much smaller, lighter models.

The 4-channel unit is a delightfuly small receiver that is simply a single circuit-board wrapped in heat-shrink. A great way to keep weight to the minumum. It has end-pins, the preferred option for most small models and certainly ideal for hand-launch gliders.

The quality of construction seems fine, with surface-mounted componets being well-soldered and no obvious "afterthoughts" to the circuitry.

Page 2 (Getting Technical)