Buzzard Droppings March 2010

I currently own a JR XP9303 radio and while the new X9503 offers several new features that I wish was built into my 9303, I wouldn’t trade one for the other, even at no expense to me.  My 9303 offers more choice than the current range of JR models due to the simple fact that it has a radio module that can be swapped out.  Not only can it use the 72 MHz synthesized module but also a variety of 2.4 GHz modules – Spektrum, FASST, HiTec, Jeti, XPS, Assan, and whole variety of modules from various Chinese manufacturers.

While Horizon/JR/Spektrum plus Airtronics have moved to eliminate modular radio systems so as to lock customers into buying ONLY their products, Futaba, HiTec, Graupner and numerous lesser known manufacturers, still provide modular radio systems, allowing customers a choice of what to use.

So why would I want anything other than Spektrum in my JR radio??  Because with choice comes the ability to choose something I might consider technically superior, save money with lower cost receivers and have the ability to easily switch to another RF protocol if one is developed in the future.

I recently purchased a Chinese 2.4 radio set for $75, which included the Tx module and an 8 channel receiver.  The company is called FrSky.  The radio set is FCC approved, uses a 2.4 hopping scheme very similar to Futaba FASST, has an extremely easy binding system, an equally easy to set Failsafe system for ALL channels and antenna diversity due to 2 antennas whose input is being constantly switched between.  The disadvantages are that there are no distributors in the US, no service center available here and they only have a 4 channel park flyer and 8 channel full range receivers available.  Of course, the 8 channel receiver only costs $38 compared with about $80 for a 7 channel Spektrum receiver.

If you are interested in a review of the system, it can be found here:  www.rcmodelreviews.com. 

The author of the review also has a video review of the system as well as a flight video of it, both of which can be accessed at the website listed above.  The author also recently put the system in a pulse jet model that he flew without incident.  A fairly harsh environment, not only due to the pulse jet but due to a lot of metal shielding being in the model.

I recently exchanged out the Castle/Berg receiver in my UHU electric glider for the FrSky 8

channel.  A bit of overkill as I currently only use 3 channels in the UHU as it only has rudder, elevator and throttle controls.  Before installing the equipment, I opened up both the receiver and the Tx module to examine the quality of the soldering and the components.  I work in the aerospace industry as an engineering tech and will just say that the quality of the workmanship was excellent, so I have no qualms about the physical quality of the units I purchased.

The glider flew just fine with solid control.  I moved my How High module into the UHU for this test and got to a height of 893 ft. according to it.  All I can say is that the glider was a speck in the sky and I’m glad I didn’t sneeze!  In any case, I had solid control of the glider the entire flight.  The manufacturer claims a 1.2 Km range (about ¾ of a mile).  My 893 ft is about .17 miles.  I know I wouldn’t be able to even see it if I was even able to get up to ¾ of a mile, so the range is more than adequate.

I’ve since converted the UHU back to its original receiver as I plan to use the 8 channel 2.4 FrSky receiver in a 3 meter electric glider.  I have also purchased one additional 8 channel receiver for use in something to be determined.  

So does that mean I’m abandoning Spektrum?  No, because Spektrum does make a variety of receivers that might be a better fit in some areas than the FrSky receiver.  I’m also not abandoning the 72 band as I’ve got lots of models equipped with 72 receivers, I have had few problems on 72 and I don’t believe the sky is falling because 2.4 equipment is available.

I do see the advantage of using 2.4 equipment at other fields and at large events where frequency control would probably be much more of a problem with 72MHz equipment than at our field.  However, 2.4 equipment has its own quirks and requirements that I’m not so sure that most modelers who have adapted the technology fully understand or are aware of.

In any case, choice is good and there are more choices available than just the system your radio manufacturer has chosen to use, assuming of course that you have a modular radio.  Good thing lots of them were manufactured before manufacturers started seeing gold in them thar’ hills by eliminating modules and our choice as consumers.

 

Rick Hanners………………..

2.4GHz Commentary