Swapping radio systems - few questions...

[ryan_m]

I'm swapping out of my current radio system (Spektrum) for various reasons that aren't important here. (Don't wanna start radio wars!)



Considering Futaba 14SG, possibly Jeti DS14, or more likely a JR XG14 DMSS or XG11 DMSS.



In my giant scale planes in the past I've always used the Spektrum Powersafe RX's. These made things easy as they did battery isolation, allowed for dual batts powering the rx and used 14 gauge wires for both batteries. Made power easy. No separate systems or power distribution setups.



So I'm clueless about how best to power a 50-60cc plane using high voltage servos if you can't use these powersafe type rx's. What's the easiest, most reliable way without spending a fortune? I'd like to have dual power feeding the rx, and then use a tech-aero IBEC to power the ignition.



And secondly, does anybody have anything good or bad to say about the above radios in use for giant scale? Either in features, or lack of them, or especially for reliability reasons?

 

[stangflyer]

ryan_m;20797 wrote: I'm swapping out of my current radio system (Spektrum) for various reasons that aren't important here. (Don't wanna start radio wars!)



Considering Futaba 14SG, possibly Jeti DS14, or more likely a JR XG14 DMSS or XG11 DMSS.



In my giant scale planes in the past I've always used the Spektrum Powersafe RX's. These made things easy as they did battery isolation, allowed for dual batts powering the rx and used 14 gauge wires for both batteries. Made power easy. No separate systems or power distribution setups.



So I'm clueless about how best to power a 50-60cc plane using high voltage servos if you can't use these powersafe type rx's. What's the easiest, most reliable way without spending a fortune? I'd like to have dual power feeding the rx, and then use a tech-aero IBEC to power the ignition.



And secondly, does anybody have anything good or bad to say about the above radios in use for giant scale? Either in features, or lack of them, or especially for reliability reasons?

For personal reasons, I would prefer the XG11 DMSS. I like the technology and JR makes a darn fine radio from what I understand. I also looked at the Futaba 14SG. Big toss up between these two. Earlier this year I upgraded to a new Aurora 9X. Simply because I had nearly $1000.00 in Hitec rx's and equipment. I can not say one bad thing about this new radio. It has "EVERYTHING" I will ever need or want. A couple of my friends have the new Jeti DS16's. They love them. But a lot of darn bells and whistles. Any of the radio's you mentioned would be great. And all new rx's. now offer dual redundancy for batteries. Really it is going to be a matter of "your" personal wants and desires. All three radio's will deliver robust and reliable service with the ease of set up you are talking about. On my set ups, I do like using Smart-Fly's Power Expanders. Primarily due to the ease of set up and robust distribution. Especially for HV servos. When we talk 50-60cc planes, (or even larger) we are well into the 2k and more figure in getting them set up. Another $150.00 is well worth it.

 

[ryan_m]

I was leaning towards the XG11 radio, but not sure why the XG14 is cheaper. Need to do some research there.

I like the JR lineup as they seem to have stuck with the powersafe type rx's, like this one: http://www.jramericas.com/233813/JRPR03428/?pcat=473

dual inputs, battery isolation and load balancing all built in.

Now I just need to find a manual and compare the XG14 and XG11 to see why the 11 costs more than the 14. Seems not to make any sense to have a lower channel number radio cost more than the higher channel one.

 

[Xpress]

Futaba all the way. That radio fits in your hands absolutely glovely. Ergonomics are almost more important than a radios programming capability (not that the 14SG lacks any programming features whatsoever) because if it doesn't fit very well in your hands then it's just more of an annoyance than a convenience if you ask me.



Hit up a local flying event or something and go check out what everybody has and see if you can hold the transmitters in your hands. As far as I'm concerned, the most important aspect is how it fits in your hands since all of the transmitters you're looking at pretty much have more bells and whistles than you'll probably ever use.

 

[DeathHorse]

I wouldn't worry about battery sharing. A parallel circuit already shares current proportional to the size of each battery. The only downside I can think of when not using a bat share is a cell fully failing short and the other cell getting overcharged by good battery. I haven't been able to find a single report of a lithium cell failing short though. Also don't plug them in at different states of charge.

 

[AEROSHELDON]

Ryan, the Futaba receivers can take a lot of amps no problem. In my 60 size (using a DA70) you can use a 14 channel rx and a Fromeco Wolverine switch with 3 outputs or more depending how you set it up. Deans in and Deans out, then a jumper is how I like to do it and actually have 6 jr plugs for power and use a Tech Aero IBEC.



You can use any switch you like. If you use a SmartFly like Stangflyer you can use an 8 channel rx with telemetry if that is important to you also.



I have been using Futaba for a long time (since '81) and can say I have never had a radio issue that I did not cause.



Realistically you can buy any of the ones you mentioned and be happy--remember this is all for fun... and they all are manufactured with reliability that is awesome if you just use common sense and set them up right. And you can get great support from the team pilots too. Buy what you want, what feels good, and have fun with it.

 

[AEROSHELDON]

Oh yeah, as you see in my signature line, I do like JR and Futaba. But my big birds get the Futaba.

 

[stangflyer]

Xpress;20822 wrote: Futaba all the way. That radio fits in your hands absolutely glovely. Ergonomics are almost more important than a radios programming capability (not that the 14SG lacks any programming features whatsoever) because if it doesn't fit very well in your hands then it's just more of an annoyance than a convenience if you ask me.



Hit up a local flying event or something and go check out what everybody has and see if you can hold the transmitters in your hands. As far as I'm concerned, the most important aspect is how it fits in your hands since all of the transmitters you're looking at pretty much have more bells and whistles than you'll probably ever use.

:nodding-yes-by-a-ve

 

[ryan_m]

I've had several lipos where one cell fails. I definitely want the isolation function of the two batteries. Don't want to just plug both in parallel style. The smart fly boards isolate batteries, and the spektrum and JR powersafe rx's all do it for a reason I figure. Just makes good sense in my head to have the batteries isolated from each other. Real world it may not be worth it, but I like the idea of it. So whether it's via a smart fly board (futaba/jeti), or the powersafe/power bus style receivers on the XG series JR,

The smartfly bat-share device is also an option, but the current limits on it and the .5 volt voltage drop aren't my ideal method to get that isolation done. That's part of why I liked the JR XG series, the power bus rx.



I've heard nothing but good things about the Futaba radios, but have also heard lots of good things on the JR XG series running DMSS protocols.

I also like that all the JR DMSS rx's will give rx voltage readouts right on the tx without separate telemetry add on units. Haven't read whether Futaba also does this yet. Still researching.

 

[AEROSHELDON]

Fromeco Wolverine switches are isolated as far as I know.



And yes Futaba can put the rx voltage right on the Tx.... not sure where on the 14 tho.