2.4 vs 50mhz and other questions

[7wt]

I am so confused with this 2.4 stuff. Please help! I read the review on the new 12X and it excites me greatly but I am a little confused why there is so many satellite receivers if the technology actually works as good as they say. Also, why do they make it in 72mhz? Then you read about all the little quirks with the 2.4 stuff and it seems a little scary. I know 72mhz is a very crowded environment but I never had any troubles, even so I am now worried about 72mhz now so I am thinking about getting a 50mhz module for my 9303. Not a ham yet but will be in a couple of weeks.

Then you have the Berg receivers that claim they actually listen to and learns your transmitter and and after it figures out your TX it will only listen to that on TX. Really? Does it work like that?

So bottom line, is the 2.4 really that good? Safe? Reliable? Is it worth selling my 72mhz 9303 to pick up a 2.4 9303? Or would I do just as well with a 50mhz module? The only downside to this is using the 770 receiver on a blade 400....where would you put it???

I am not trying to stir up any trouble, just to understand what is best for the average sailplane guy turn heli freak. Am I over-thinking this all? I would like to be involved with the new technology but not if it is going to buy me trouble.

[BarracudaHockey]

If you're flying 50mhz and dont worry about frequency conflicts the value of 2.4 will be somewhat less to you personally.

However there is still interference generated by dirty bearings and such that will be ignored by 2.4 systems that can/will effect 50mhz stuff. Don't get me wrong, I'm not saying that 2.4 is a substitute for proper building and maintenance.

Futaba doesn't use the dual reciever technology that Spectrum does due to their frequency hopping technology.

If you're studying for your ham ticket then you know that higher frequencies are more subject to shadowing then lower frequencies. The dual recievers prevent shadowing by things such as batteries, carbon frames, engines, and the like.

[Pinecone]

Futaba extends their antennas out further from the Rx to give spacial diversity. Spektrum uses sats. The large Rxes are more likely to go in larger more expensive aircraft, so the multi Rx concept give redundancy. Giant scale guys ahve used multi Rxes for years, even on 72.

The 12X comes in 72MHz, mainly because 2.4 GHz is not leal in Japan, where they are made. So they have to still support 72 MHz.

You will find that 50 MHz stuff is getting hard to find. No one makes it any longer. You can find modules and Rxes occasionally, but you can't just go to your LHS and get one, or even hop on line nad have one in your hands in a few days. Plus you still have long Tx and Rx antennas.

2.4 GHz works fine, better than VHF. But NO RF link is perfect. The same thing happened with 72 became available, with all the hype people expected to never have any problems, but we know that isn't so. Just as many aircraft crash from VHF gear, and IMO, from the same causes (lack of voltage to the Rx and servos), but it gets passed off as "a glitch." 2.4 has forced us to look at what is actually going on. And in fact, early Berg Rxes pointed the way to our low voltage problems with in flight resets, and they were "fixed" by changing the firmware to allow a quicker reboot/relink.

Yes, Berg with DSP "learn" your Tx signal characteritics, and will only respond to that Tx, but if two people have their Tx on, on the same frequency, the Berg will not respond to the second Tx, but it might not be able to "hear" the prper Tx and will go into fail safe.

Proper your 2.4 GHz Rx with enough voltage (at least 3.5 volts) and it will be fine. Perfect? No, but better than 72 or 50.

[7wt]

Thanks again Pincone. I was a little concerned about finding the 50 stuff and you just confirmed it. I decided to get the X9303 and try to sell my XP9303. I should get it sometime next week so I am pretty pumped. New tech scares me a little and it seems like everything I read in the magazines is pushing the 2.4 and it was making me a little scepticle. I guess I will just be real careful to pay attention to the input voltage and get a BEC and I should be fine...right?

[Pinecone]

Make that get a GOOD BEC. :)

Most people are having no problems. The polls, which tend to over count negative instances, has something like 87% of the people without ANY problems.

[7wt]

Which one would be a good one? Which ones do you say away from?

[Pinecone]

Dimension Engineering are good, Castle seem to be doing well once they got their chip installer working right. Hercules are good. In the Finless Tech Room there is a thread on making yor own.

Basically any of the name brands are fine, as long as yo don't over load them.

I have a long term project to test BEC for voltage drop under load.