Hey guys,

Another stupid thread I know, but I'm just trying to learn, and I guess you guys are the best to help!

I was wondering, what would be a good receiver and radio combination?

In terms of radio I was thinking maybe something like a JR 7 channel (XP7202), but I looked it up, and I don't know that it is that easy to get in Adelaide, and also what would be a good receiver for something like this? I have been told this radio doesn't have 'crystals', can someone please tell me the benefits and drawbacks of having crystals?

Cheers,
Kendall

G'day Kendall,
If I were you, & was going to buy a new 7 channel radio, I would go for the Spektrum DX7,
Similar price to the JR, & be aware, when you buy a radio set, everything come's with it, Transmitter, receiver, batteries, servos, switch & charger.
The JR 2720, has a synthesized TX & RX, so you don't need crystals.
Check out the Spektrum here. http://www.spektrumrc.com/
Check out JR here, http://modelflight.com.au/
They are both available at Modelflight in Adelaide South Australia, they are the importers,
right at your doorstep.

Allan is right. The DX7 is a great choice and is the radio of the future. No interference, no frequency pins, no sweat. Great system. Well worth the money. Consider that you get four quality servo's that retail for about 40 dollars US each.. a great choice.

DS

Hi

I agree with alan, the dx7 is what i'd buy if i was starting flying now, no crstals and no worrying about frequency pegs.

Simon

Hey thanks guys,

I like the DX7. I don't know much about the quality of either JR or Spektrum, but I was up until now under the impression that JR was superior in quality, was I mistaken?

I was also totally unaware that the radio came with the receiver! (I knew it came with the servos).

Thanks again

I actually like to recommend that new pilots wait until they contact their instructors before they buy a radio, if possible. It will make things go alot easier if you get the same type of radio that your instructor is using. That way he will be setup for a buddy box. In addition to knowing your radio so he will be able to help you in setting up your radio and your plane.

Hope this helps

Ken

Cheers for the advice, but I still think that I am going to get a radio for me, instead of for my instructor.

Cheers

I'm not saying to buy a radio for your instructor. But it helps if you have the same brand of radio that your instructor has. That way you will have a buddy box available for use. Plus since he will have the same brand of radio that you have then he should be familiar with your radio in order to help you setup your radio and plane.

Ken

I'm sittin' on the fence on this one. I agree with Ken about talking with whomever will be instructing you before buying, but in this case I'd be looking for someone familiar with DSSS to help train me. As fast as this is taking off (pardon the pun), Spread Spectrum is the way to go because of all its advantages regarding frequency conflict (total absence of), RF interference (total absence of), and the added cost of buying an FM system and later upgrading to DSSS, when you can start out with the latest technology. At $350USD, it's a heck of a deal. I know, it doesn't have a jack for "buddy boxing", but it isn't all that difficult to pass the Tx back and forth, as long as you follow the "three mistakes high" guideline. I've played with the system a little, it's an easy system to get used to; there are already three of the DX-7's in my club, and tomorrow there will be four. I'm not giving up my 9C Futaba or changing the planes I have, but all my planes from here on will get DSS systems.

Hey is the idea of 'buddy-boxing' for two radios control the one plane, so when the instructor feels they need to take over, they can just use their radio or what?

I'm a bit confused with the whole 'buddy-box'. I do agree with khodges though, that passing the radio is the best way to go.

Cheers

I agree and bought a Futaba since our club's buddy box is Futaba compatible. Only I did make a boo-boo and bought a PCM system rather than FM. The buddy box wouldn't work with the PCM electronics. I had a choice of buying a new PCM TX to use a my own buddy box or to get a 2nd receiver - this time FM. I chose the latter.

Now that I've soloed and graduated off the buddy box, I've returned to the PCM stuff. For your first radio, get a FM based dual conversion set. A budget system will work but I'd recommend at least a 6 channel with computer programming features. You may not need the programming while learning but will definitely use it shortly thereafter.

Really? The manufacturers are going to be shocked to hear this as they are installed in them at the factory. Someone must have stolen them from the boxes you saw. The DX-7 "buddies" with JR radios of most types. JR actually produces these radios for Spektrum too so you can see why. The standard JR mono-pin buddy cable is used. All you really need to do is make sure there is a JR type buddy box available for you instructor to use which could include the Quatro even for a simple trainer. Stay away from mixes and dual rates and such as the buddy box may not be able to emulate those features.

Dale,
I've instructed more students than I can even count and I have "passed the radio" on more than one occasion. I won't instruct that way any longer. Why? Because there are times when the student "thinks" they know more than the instructor and doesn't think they need any help, and won't hand the radio back. I've even had one student turn away from me when I tried to take the radio back. When the student thinks he knows more than the instructor then it's time for the instructor to walk away and let the student crash. One of the jobs of an instructor is to know when to take the plane back from the student, and when not to. Trust me here, I've seen plenty of times that the student thought they had it but if I hadn't taken the plane back they would have crashed. The bottom line here is the instructor needs to have the ability to take control of the plane WITHOUT the student being able to interfere.

Ken

Hey, because you instruct I respect you and your work, and for any other instructor it is the same. So I'm not going to dispute your point, as it is your experience, and I don't doubt your experience 1 bit, but because I respect instructors I will listen to every word and when they say "hand over the remote", I will do so.

Cheers

G'day Kendall.
As an intructor I can tell you that a buddy box setup is THE best way to save your plane, espectially when learning to take off & land.
All it is, is another radio, connected to yours, you hold the slave TX, & the instructor holds the master(your TX), when the instructor holds a button down, or a switch, whatever, you have control of the plane, & if you get into trouble, he releases the button, & can save your plane,
All this happens in a split second, whereas getting a TX back from a student, can take seconds, & sometimes, too long to save the plane. It is up to the instructor to decide when to take over, of course.
As was stated by RCKen, make sure that the instructor at the club has JR, which is what I have, or a radio that is JR compatable, like a Spektrum, & then buy whatever you find is the right one.
And you may find that because, Modelflight is in Adelaide, there will be a lot of JR radio's there anyway.

Well I guess that is another thing I will look into when I go to a club, before I purchase things like radio gear. I am currently on holidays in NSW, that's why I can't just go to the club or buy a plane for anyone who thinks I'm "just talk".

I'll let you know what happens after I go and visit the local club (which I have already located) and after I can get some gear!

Cheers

Basically yes. The instructor holds the Master radio and the student holds the buddy/slave unit. As long as the instructor keeps a trainer switch activated on the master the student will have full control of the plane. If/when the student endangers the plane or manuevers need to be done that the student is simply not ready for (landing) the instructor releases the training switch on the master and INSTANTLY has full command of the plane. The best part of this is that the instructor doesn't need to chase a hesitant student around the field trying to get him to surrender the radio. Too often I've seen students who "just knew" that they could save a plane refuse to surrender a TX and end up destroying their plane. Their response is usually: "Darn, so close". Yeah, right.[:'(]

G'day Kendall
Where in NSW are you holidaying?
I'm on the mid north coast, near Taree NSW.

Hi

I instruct and would normally use a buddy box system if possible.

The instructor holds a spring loaded switch to pass control to the pupil as soon as the switch is let go of the instructor regains control. this is far safer than passing the transmitter back and forth, your plane is far less likely to crash. When practising landings and take off if you get it wrong theres not much the instructor can do about it without a buddy box

When i wrote my previous post i was under the impression that the dx7 could be buddied to other tx types. but having downloaded the manual it suggests that it is only other buddyable to other spektrum ones.

I have seen a site on the net which gives details of how to wire virtually any tx to any other tx no doubt in time the same will happen for the dx7.

simon

In several threads in the radio support forums, Danny the JR/Spektrum rep has stated that the DX-7 is trainer compatable with other DX-7's and most JR's.
http://www.rcuniverse.com/forum/m_5066406/tm.htm

Very true RCKen but now that Futaba and JR can link up together that eliminates some of that problem. I just seen the link it the other day I wished I could remeber where I seen it. They now have a link that has JR and Futaba links on them so you don't have to have the same box.

However I am hearing and seeing a lot of the guys at my airfield are switching to the Specktrum. Apparently it is getting to be a hot item. No one can get it here in Ohio from any shops until mid to late Feb. And our Airfield is adding on a new section to the Freq. board because so many people are using the Specktrum.

Also we a spot in our NE corner that apparently has a microwave going through because a lot of guys have lost control of there plane for a couple of seconds and now that they have the Specktrum it isn't doing it. So it sounds like a miracle transmitter coming.

OOPS, how'd I miss that? I flew a guy's plane with one (no take-off or landing) and have played with the programming sequences to see how it differed from my 9C, and I even turned it over to look at the back, I didn't see the jack for the cord. My bad.

I learned without benefit of the buddy box, but learned from a guy who was not only a good r/c pilot and instructor, but had been both fixed wing and rotary wing instructor in the Army, a no-nonsense approach that when he said "gimme the radio", he got it. My ego was no bigger than my wallet, I didn't have a problem letting him save my arse.

As for those fledgling pilots who refuse to give the Tx back, you just can't protect some people from themselves, and the learning curve for them needs to be steep and severe. A few crashed planes can shrink an ego down to size fairly quickly, as well as a wallet.

hello dale8888 i'm in perthw.a and here at the moment the maaa is investigating the dx7 wether to see if it is viable to use and to see if it is safe to use. some of us is a bit slow over here or to old to change. My self i have no use for one i have a pcm 9xseries2 which I fly my planes with. I have changed rx and the tx module to full synthesized no crystals yay. I don't know much about the tx that you are asking about but when I started out I went to the club here in perth to find out what they are using. majority where using jr. they told me of far do i intend to go or was i happy just to fly one plane. In the end I brought myself a 3810 which is a jr 8 channell radio

the best thing about using a buddy box is that the instructor can allow the student much more time to correct his mistakes whereas tossing the box requires the instructor to take a moderately in trouble plane away from a student that might be able to recover. It makes for a faster learning curve. Also the instructor can be more relaxed. I myself personally learned on the transmitter toss method and I was a fairly good student and I had excellent instructors. My instructor one time got so complacent with me doing circles that when someone came over to talk to him and he responded to them that he forgot he was instructing me and walked away talking to him. Needless to say 3 minutes later I was out of fuel and yelling dead stick. Thankfully I was flying a duraplane because after that ugly of a "landing" which I was not even up to making approaches yet, I was still able to fly. Actually that was the only time I was ever happy I had a duraplane. It flew like a guided missile no float at all but when I did master it all other planes after that were fairly easy

Hi bruce

Thanks thought that was the case fairly typical that the manual dosn't mention it.

Simon