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aaron_gx

Need a new radio... What kind, and PCM, or PPM?

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I just finished my first FPV plane, an easystar, and the video link works excellent now... Now, I'm being limited by my 4ch chinese 72mhz radio and RX. I got out a about 1000' and it starts glitching like crazy, and cause a minor crash. I know the area is about as quiet for RF noise as it gets, so I beleive its time to upgrade to a better controller and receiver.

I was looking at possibly a Futaba 6EXA package. I was also looking at a JR SX600 on ebay aswell. I am relatively new to the RC scene, so bear with me... I dont have a lot of cash to spend, and these were relatively affordable. Will I get the kind of range I need from one of these units? Anything HAS to be better than my current setup. I would also like the 2 extra channels available for future pan/tilt & ailerons. (I am already using panning on the 4th channel).

Would a BERG reciever be better than the standard futaba or jr recievers?

And finally, for aircraft use, is PPM or PCM a better choice, and why?

Thanks in advance,

Aaron

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I ended up buying a futaba 7caf 7 channel transmitter with a R168DF reciever. Do you guys think this will give me acceptable range for FPV piloting? I read good reviews about it, and dropped more than I expected to on it, but I think it'll be worth it in the end.

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I can't help much as I don't use any of those radio's but I will say choose a good TX like Futaba and make shure you get the best receiver you can afford. Having said that I always use PPM and NOT PCM as I and some others would rather have control with glitches than not control at all. A few years ago I had to watch my glider circle down in front of me using PCM. After finding the glider there was no damage and the radio was working fine.

I like the little warning of the motor kicking you get with PPM when you are running out of range or in interference.

With some modern PPM units having pulse processing and fail safe they IMO are better than PCM.

Terry

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The 7C will certainly be of some help, but don't forget there are many other variables on each setup that affect the range. Don't go far away as fast as you can on the first flight, but go away progressively judging the link quality.

Personally I like using a PPM RX to determine a new setup, maximize range with it by doing the required shielding / component placement while having a good feel of the result in flight, then once I know it's OK I switch it for a PCM one to suppress all those slight glitches you often have with PPM even with a relatively good link. I'm thinking mainly of the camera pan/tilt servos, it really annoys me when those twitch.

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Good point about the pan and tilt glitch but it dose give you a clear warning all is not well.

Terry

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Terry, you said get the best reciever affordable. I am finding very little information on the topic of long range recievers. What constitutes a good reciever?

The one that is coming with my radio is a Futaba R168DF, with dual conversion (whatever that is...). Its equally as expensive to purchase new as a 7ch BERG reciever, which would give me better range & reliability? I will need to purchase a few extra recievers for my other models aswell.

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I recall seeing some discussions in the various R/C forums about excessive glitches with the Berg 7-Ch when used in FPV apps. I don't have any links, so try using Google to see if you can find any discussions about such things.

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Aaron,

you will need to do some digging yourself on this on as I said I don't use 72Mhz or 35Mhz ( where are you located ). Yes duel conversion is good, I used Multiplex IPD receivers until I went to 459Mhz.

Terry

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