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What 2.4 GHz Radio?
Posted: Tue Mar 29, 2011 6:57 am
by Dirtdiver
I'm looking to step into the 21st century and retire the Futaba Magnum Jr. I've taken a quick look at the 2.4 Ghz radios out there (Futaba, Airtronics and Spectrum) and am not sure what to buy. Can anyone tell me if there really is a difference between brands in terms of quality and reception?
The few tracks that I have been to recently are a mixed bag. For off-road, most of the people that I have seen run either Airtronics or Spectrum but for on-road/oval, quite a few run Futaba. What do you run and why?
Re: What 2.4 GHz Radio?
Posted: Tue Mar 29, 2011 8:53 am
by jwscab
they are probably all pretty good.....the only thing I can say is to check the prices of the receivers. If you have multiple models, going with cheaper receivers will save you in the long run...
I know that is one problem with futuaba for flight gear. they make a nice and nicely priced 6 channel radio, but then the receivers cost way too much to install in all your models.
otherwise, check the features, and if you can put them in your hands to try out the 'feel', that is always a good thing.
Re: What 2.4 GHz Radio?
Posted: Tue Mar 29, 2011 9:21 am
by tim.sanderson
jwscab wrote:they are probably all pretty good.....the only thing I can say is to check the prices of the receivers. If you have multiple models, going with cheaper receivers will save you in the long run...
Agreed. I race with my Spektrum DX3s and I love it. The receivers aren't the cheapest, (I think they are $80 or so) but if I remember correctly, I think I got two of them with my radio. I've also scooped up a few used SR3000 receivers for pretty good deals... $30 or $40 each. They aren't the smallest of the Spektrum receivers, but they definitely aren't what I would consider 'large'.
The interface is great too. Very easy to navigate through the settings. A buddy I race with recently broke his high end Airtronics radio, and bought a Spektrum DX3r pro to use as he waits for it to get repaired. He couldn't believe how much easier it was to set.
I've had 2 Spektrum radios, and have nothing but great things to say about them. That being said, I've personally never used any 2.4ghz radios other than Spektrum, so I can't really give you a comparison between different makes.
*EDIT* I forgot to mention it is super-light weight, and only uses 4 AA batteries.
Re: What 2.4 GHz Radio?
Posted: Tue Mar 29, 2011 10:01 am
by badattitude
Check the Airtronics MX Sport or MX3.
I use the MX Sport. It is cheaper than the MX3
Pros are that is has a lot of adjustment for the low price
Cons is that it's cheaply built
It works very well. I upgraded from the Futaba Magnum Jr.
The range is amazing!
Re: What 2.4 GHz Radio?
Posted: Tue Mar 29, 2011 2:21 pm
by RCveteran
For race cars, I run a Airtronics MX3-X, I think it is all you would ever need. Cons are receivers are $80 or you can use older FHSS2 and can get those for around $50 but not cheap.
For bashing cars and old vintage stuff to put around with I have a mixture of old radios and even a newer traxxas 2.4Ghz that work fine and recievers can be had cheap.
Re: What 2.4 GHz Radio?
Posted: Tue Mar 29, 2011 2:53 pm
by fredswain
Why are people running 3 channel radios today? I was looking at a Spektrum DX2S and for the life of me can't think of a reason why I'd need a 3rd channel.
Re: What 2.4 GHz Radio?
Posted: Tue Mar 29, 2011 2:56 pm
by kaiser
one reason for 3channel, recivers anyway, is to power onboard transponders. thats what i do with my 3rd channel port anyway.
other vehicles actually use a 3rd channel, like crawlers with locking diff's.
Re: What 2.4 GHz Radio?
Posted: Tue Mar 29, 2011 3:13 pm
by fredswain
So if I decide to race and need to power a transponder, how do I do it if I only have a 2 channel? Can I use a 2 channel transmitter but with a 3 channel receiver to power a transponder?
Re: What 2.4 GHz Radio?
Posted: Tue Mar 29, 2011 3:26 pm
by tim.sanderson
fredswain wrote:So if I decide to race and need to power a transponder, how do I do it if I only have a 2 channel? Can I use a 2 channel transmitter but with a 3 channel receiver to power a transponder?
You can always use a y-splitter, to split one of the other channels. Unless you are running nitro with a battery box powering the servos, or something electric that doesn't have a BEC, you can also run the transponder out of the 'battery' plug. If it has a 'bind' plug, you can use that too.
(that's a marine rx... it's the only 2ch rx I came across on google. It's just to show what you'd use.

)
Re: What 2.4 GHz Radio?
Posted: Tue Mar 29, 2011 3:34 pm
by fredswain
I was looking at the receiver that comes with the DX2S yesterday. It is an SR3300T which has 7 ports on the receiver.
1: RPM
2: Temp
3: Lap
4: Aux
5: Thr
6: Str
7: Bind/rs
I'm not going to need rpm, temp, or lap. The others I don't know anything about. I'm assuming though that since it has Bind, that I won't have a problem running a transponder. Is that correct? To me it seemed like the only real advantage I'd have by going up to the 3 channel DX3S is that it has a much larger model memory to it. This one only does 5. I have 3 cars so that's plenty.
I was told that I can also still use my old Tekin speed control and Futaba or KO servos for the time being until I decide to update those later. Again, is all of that correct info as well?
Thanks for the help so far guys!
Re: What 2.4 GHz Radio?
Posted: Tue Mar 29, 2011 3:58 pm
by tim.sanderson
My first choice would be the AUX input. 2nd would be the BIND input. I can't remember if I read somewhere that plugging something into one of the telemetry inputs was bad. But like I said, use either the AUX or BIND and you'll be fine.
Re: What 2.4 GHz Radio?
Posted: Tue Mar 29, 2011 4:28 pm
by tim.sanderson
I got this out of the manual:
(
http://www.spektrumrc.com/ProdInfo/Files/SPMSR3300T-Instructions.pdf)
Note: The telemetry sensor ports are regulated at 3.3 volts and cannot be used to power a transponder. If using a transponder it must be plugged in the battery or one of the channel ports to operate properly.
That was it. No damage will come if you plug a transponder into a tele port, it just won't work.
Stick with BIND or AUX.

Re: What 2.4 GHz Radio?
Posted: Tue Mar 29, 2011 4:38 pm
by fredswain
It appears to be a 3 channel receiver but packaged with a 2 channel transmitter.
Re: What 2.4 GHz Radio?
Posted: Wed Mar 30, 2011 7:39 am
by kaiser
fredswain wrote:It appears to be a 3 channel receiver but packaged with a 2 channel transmitter.
i use a futaba 2pl 2.4ghz which is two channel but the rec it comes with is 3 channel. the 3rd channel is pretty much just a power point for my transponder.
Re: What 2.4 GHz Radio?
Posted: Wed Mar 30, 2011 9:58 am
by fredswain
Sweet. So it does work. I didn't see why I should go up to a much more expensive 3 channel transmitter and now I know that I don't have to. 5 car memory is plenty for me and the price is good. Thanks for the help guys. Now it's time to go figure out brushless motors, speed controls, lipos, and charge rates! What happened to the good old days where you just bought an ESC, a battery, and a motor and just installed them?
