abufletcher

For a second time I've experienced a transmitter failure on the Airtronics RDS8000. Once before a wire broke inisde the Tx gimbal resulting in the total loss of the model. Today, it appears that the same thing happened on a second RDS8000, though luckily this time on the ground.

I've been getting my Sopwith Snipe ready to fly again and noticed something odd about the aileron setup. It appeared to be just fine and then the next time I switched on it was as if the settings had changed. That seemed weird enough. But then the ailerons stopped responding completely even though the rudder, elevator, and throttle were still fine. So to confirm my suspicion that it was a Tx problem I tried with another model. And sure enough, the rudder, elevator, and throttle worked but the ailerons went to a non-neutral position and then ceased functioning.

And the functioning never return. So I believe that if I open up the RDS8000 I will find a broken wire on the aileron gimbal just as I did before. I'm lucky that this happened AFTER the first flight.

This is definitely a quality-control issue with the RDS8000. Sure, I have used this radio for many years, but the wires are really thin and the attachment points don't deal well with repetitive stress. Eventually, the wire WILL fail.

*****

At this point, I don't know what I'm going to do. It seems foolish to get another RDS8000 (which amazingly is still on the market). I could upgrade to the SD-10GS, but frankly, I don't know if they are any more reliable unless Airtronics has specifically addressed this concern while designing the SD-10GS.

Alternatively, I could make the move to Futaba or JR. But that would mean also buying a new set of Rx units.

Looks like I won't be flying for a while.

abufletcher

I assume that Airtronics/Sanwa servos are compatible with a Futaba/JR Rx. (I know that Futaba servos can be used with Airtronics, if you cut off the little tab.) If I go with Futaba it would probable be the 8JA:

http://www3.towerhobbies.com/cgi-bin...&I=LXBWGR&P=ML

abufletcher

Quote from one of the reviews of the RDS8000 on Airtronics own website. This is EXACTLY what I experienced today. (And what almost certainly happened in the air last time.)

"I've had mine for about 1-2 years and have had repeated cases of the wires inside the TX breaking...this last time costing me my airplane. They short out, then break, leading to full deflection of a surface. Research it, multiple cases. I'm sending in to get fixed, we'll see about the cost. I really like the controller, but it's not worth it. (Posted on 4/1/14)"

invertmast

My Feedback: (23)

If its that much of a repeat problem, theres no way i would ever buy or repair it again. My time is worth more than a $800+ tx/rx system.

jester_s1

Airtronics, like all the other brands, have a proprietary 2.4ghz protocol that isn't compatible with anything else.

The wire issue is well know with the RDS8000 radios. It was really bad on the early ones but a tweak to the wire length improved things considerably. A dab of hot glue or thickened epoxy on the solder joints will protect them from the repeated bending, fixing the problem for good. This should be done at the factory, but it isn't.

I agree this radio really shouldn't still be on the market. It already was behind the game when it was first released with respect to features, given that it was just a 2.4ghz version of the RD8000. But is was cheaper than most 6 channel systems at the time so it sold. The SD-10G doesn't have this problem because it uses an altogether different system for the gimbals.

The thing is though, unless you're invested pretty deeply in Airtronics receivers, it doesn't make sense to me to buy another Airtronics radio. The company hasn't done any real product development for a solid 5 years and doesn't look like it will in the foreseeable future either. While all the other brands have made telemetry, voice prompts, vibrating alerts, and a few other useful doodads standard on their radios, Airtronics is content to offer the same old stuff that we had 10 years ago. They are well made (aside from the gimbal issue), but Airtronics really isn't competitive in today's market. Have a look at what Graupner is offering; they have the best value in the hobby today IMO. And, of course, you can't go wrong with Futaba or JR either.

abufletcher

I've been putting off a move to Futaba (or JR) for several years, but I suppose now it's time. At this point, I have 5 functioning Airtronics receivers (4 in models and one on a test-stand setup). I do still have another RDS8000 that I could use for "Sunday flyer" type models (i.e. cheap ARFs), but with my special scale models I should get something better. I could start with just two new receivers (for the Snipe and SE5a) and the Futaba 8JA, which would come to about $450.

I agree that Airtronics isn't moving forward. And even though they are ultimately Sanwa, they are virtually unknown in Japan (where I live).

abufletcher

Just checked on a third model (the SE5a) and yes indeed the ailerons go to maximum deflection and then cease functioning. In flight this would guarantee destruction. The first step is to record all the current settings for all my models (and transfer them to a still working RDS8000 as back-up). At that point, I may open up the broken Tx and see what's up.

Here's a link to the RCU thread describing the last failure (in 2013). The photos show the broken wire on the aileron gimbal and the description sounds identical. Yeah, I think it's time to say good-bye to Airtronics. It was a good radio to learn on but now that my models are more serious, I need a more serious (and more dependable) radio.

http://www.rcuniverse.com/forum/airt...e-failure.html

abufletcher

While transferring the settings, I came across some interesting stored data. The INT function records the total time that the Tx has been switched on (up to a max of 99 hours and 59 minutes). Of course, this includes both flying time and any setup time. My "old" RDS8000, which I have used less frequently because of a crack in the antenna housing, registers as having 22 hours 59 minutes of use. The "new" RDS8000 (the one that just failed) registers 75 hours and 5 minutes of use.

Now I'm curious whether I can get power restored to the older failed RSD8000 and check how much time was on that Tx before it failed.

*****

Old failed RDS8000 total time: 99 hours and 59 minutes. Hmm...so that's the max and apparently it doesn't reset itself so all this tells me is that it had been in use AT LEAST that amount of time. (Apparently, the point of this function is to be able to track Tx battery use by manually resetting it each time the Tx battery is charged).

Truckracer

My Feedback: (19)

Three of us in our club bought RDS 8000 transmitters when 2.4 radios first came out. All three have experienced the same wire failure though only one failure resulted in the loss of an airplane. I repaired these three transmitters using more flexible wires in a different configuration and I doubt these will fail again. There was quite adequate strain relief in the original configuration so that wasn't a problem with our transmitters.

For the record, the original problem was the result of using wiring that had limited flexibility configured with too short of a loop / cable to allow for the required flexibility.

Most stick assemblies regardless of mfgr. use a similar wiring configuration to what Airtronics uses. Airtronics just had poor implementation of the wiring in this case combined with a poor selection of the wire they used for the application. With a proper repair, there is no reason to fear the problem repeating.

abufletcher

What makes one wire "more flexible" than another? Did you switch to a thicker gauge wire? The wires look incredible flimsy to me. Some people have suggested putting a dot of hot glue or epoxy over the solder point. But in my case the wire broken in the middle. Obviously this is the result of repetitive strain (from a too short loop).

*****

I just checked and it was the same red wire on the aileron gimbal that broke. This time it broke a bit closer to the solder point.

abufletcher

The first photo shows the recently failed RDS8000. The second shows the one that failed two years ago. Same red wire on the same aileron gimbal.

otrcman

I had a red wire failure on my RDS 8000 also. And, like Don's, my wire broke some distance from the solder joint. So a daub of hot glue wouldn't have changed anything. I didn't lose an airplane, but it could as well have failed in flight as during shop setup.

But overall I have to say that my Airtronics radios have been the most reliable brand I've ever seen in 57 years of RC flying. I've seen lots of crashes due to radio problems, but chose Airtronics because they seemed to be the most trouble free. And I still believe that.

Dick

jester_s1

Wow, I can't imagine a wire breaking like that unless it had a strain point in that spot or either was a defective wire from the factory. A number of people replaced the factory wire with a length of servo wire for the gimbals early on. Servo wire is a good bit thicker and so more durable. Yes, it's probably a couple of hours' job to fix it, but with the reliability of Airtronics radios otherwise I think it's worth it.

abufletcher

It really does seem like a serious CQ problem that it is ALWAYS the red wire on the aileron gimbal. That's not random.

I guess it won't hurt to try to repair it. It will certainly test my soldering skills. If it works, it works. If not, then I was going to have to get a new radio anyway. I do like the simplicity of the RDS8000 (otherwise I wouldn't have bought 3 of them over the years) and since my WWI models doesn't need fancy 10+ channels, it does almost everything I need it to. It doesn't however offer throttle curves and with the Seidel/UMS that would be a big plug.

foodstick

I do some slot car racing, and they sell a silicon wrapped wire that is common on slot cars guide pins so that it will swing back and forth ..and even act as a spring. Now admitted the wire does come loose and break .. but that is after numerous HUGE impact crashes.

I think that type of wire which I assume is available for many things? would be a good substitute....


http://www.fantasyworldhobbies.com/1...ad-wire-50-cm/

Now that I think of it RC cars probably use it as well ?

Anyhow If you decide to go Futaba.. I am using their older FASST setup.... I can say two things truthfully, the receivers are expensive. And, I don't think I have ever had a radio failure in the 7-10 years I have used it....

raptureboy

I own the RDS 8000 and early on it was noted the wire was an issue. I opened mine and made sure there was no strain issue. I have moved to the SD10 and really it has all the features I care to try and learn. I personally don't really need to know all the information they try to sell you on. Like my car and my phone it's just TMI You can't beat the price for what they have though and if you think these have problems just search Spectrum. Now there is a fireball I would just fix the wires and be done with it a good radio repair shop ought to be able to handle it for you if you don't feel up to it.

otrcman

Foodstick makes an important point. Not all wire is created equal. Copper, as used in electrical wiring, presents a real dilemma. Yes, it's an excellent conductor. Yes, it solders readily. Yes, it's fairly corrosion resistant. Yes, the cost is nominal. But does it resist fatigue well ? No, as a matter of fact it's quite poor in fatigue.

So, why do they use copper when the fatigue life is poor ? Because all the other properties are superb and most applications don't involve much flexing. Plus, designers have found ways around the fatigue problem. The "way around" is to make wire with many small strands rather than just a few large strands. The many-strand wire flexes easily and the individual strands don't see as much stress as a wire with few strands.

The new wire that you use needs to be of a type that is designed for applications where flexing is a concern. Rather than using the first wire that comes to hand, I'd suggest that you do some internet research and find wire that is designed for long fatigue life. I just did a quicky google search and the first candidate source looked pretty good, although I don't know the price or what their minimum order would be.

http://www.daburn.com/2671UltraFlexi...E15681692.aspx


One last thing: Don't make the mistake of thinking that bigger wire would last longer. Yes, a bigger would be stronger for a single pull. But the flex life of a bigger wire over a given radius is not as good. Try to use the same size wire as you found in your transmitter. somebody else in this discussion might be able to look at the wire and tell you what size it is. I'm no good at that, but think it is in the 26 or 28 gage range.

Dick

otrcman

One other thought regarding flexible wire and the RDS8000:

If flexible wire is so readily available, why did Sanwa use a wire that wasn't up to the job ? I'm sure they didn't mean to make such a mistake. They probably used wire from a different vendor, or their existing vendor changed specs, or they just took a chance on a cheaper wire and assumed it would do the job. Or maybe their vendor made the wire incorrectly and didn't know it until there were thousands of units sold. Everybody makes judgements like this in the competitive world. If a manufacturer uses only the "best of the best" throughout in a design, the final product will too expensive and won't sell in the competitive marketplace.

Dick

BelAirBob

Why not just send the transmitter back to Airtronics for wire replacement. They may not even charge you since it was a known problem. I have one of the early RDS8000 and never had a problem except for the flimsy antenna that most 2.4 radios have. I have also been using been using Spektrum for years without a problem. But being tired of babying the antennas, I got a new DX7 with the solid antenna. To the dismay of the Spektrum haters, no problem with it all last season after a few hundred flights. The Lipo battery is great too.

bob

abufletcher

I got an email yesterday from the Airtronics service department. They told me to send it to them. Great. I'm in Japan and they are in California. But I will be in that area in late March so potentially I could bring the radio with me and have it fixed during my stay. (BTW, has anyone had any problems bringing RC radio gear as checked luggage on airplanes?) They also mentioned that they have a trade-in program where I trade in my RDS8000 for a discount on a SD-10GS. They haven't gotten back to me yet on the amount of this discount.

You're right that the antenna housing is very weak. In fact, it's broken on two of my three RDS8000 radios. Curious, in addition to the broken antenna housing, a corner of two of bodies has also broken off (but is held in place with the screw joining the two halves). In both cases it's broken off in almost exactly the same way in exactly the same spot (upper right corner). Shows there must be some inherent weakness at this point. I ended up hot-gluing the broken antenna housing in place. None of this is too surprising when you do the math and calculate what the Tx is actually worth. I was able to buy my RDS8000 for around $120 on sale (at Hobby People) that included a Tx battery, Rx, Rx battery, charger, and switch. Subtract all that stuff from the price and you come up with something like $25 bucks for the Tx.

Once thing I really like about the Futaba 8J is that the antenna is ENTIRELY internal.

otrcman

I sent my RDS8000 with broken wire back to Airtronics for repair and they did the job for free. Hopefully the replaced wire wasn't of the same batch as was used to make the transmitter originally !

I bought an SD-10G a couple of years ago. It has some features that I like. And yes, I did look at the way the wires are routed to the stick gimbals. Entirely different design. One of the things I didn't care for was the greater thickness of the new transmitter. I've got small hands and didn't feel like I had a comfortable grip on the box. Jack Albrecht (Airtronics technical advisor) encouraged me to try a neck strap and I have come to like it.

Dick

abufletcher

In the second email from Airtronics they confirmed that the SD-10GS uses a different gimbal design. They also said that the trade-in price would be $279 (down from the $399 list price so that's pretty good). I don't know if I'd just bring in the busted Tx or whether they'd want the entire "package" of Tx, Rx, batteries, etc. I assume just the Tx.

Unfortunately, they don't accept direct customer drop-offs at their repair facility (in Fountain Valley, CA). But told me that I could put in a repair request at the Fountain Valley Hobby People store (which is just around the corner). That's fine if they could get the work done in time. I'll only be in the US from March 16 to March 31. I suppose I could ship it from here (which would probably cost $20-30 bucks) and they could ship it back to my SoCal address.

As far as how the repair was done, I doubt very much if they change to a different wire. They probably just add a bit more slack and maybe the globs of hot glue (if that wasn't already there).

I have managed to transfer all of the failed RDS8000 settings to my other, still functional, RDS8000. So at least I can fly my ARF until March. I think I'll hold off on flying either of my WWI scale models until I determine what I'm going to do about a new or repaired Tx.

TFF

I would trade up or change brands. That is a pretty easy fix to do your self; yes it is your fault if it breaks. If Airtronics fix breaks, there is no different outcome. With all the flying wires that WW1 planes have, I would get Futaba FASST to the latest JR protocol. I would not get the Spectrum. Not that others will not work, but If you are not willing to bet in soldering your own wire, I would not bet on lesser technology if better is out there. This is a guy that still flies 72mhz. I personally think the Futaba is the better one. Still a chocolate vs vanilla discussion.

jester_s1

The soldering skills aren't terribly demanding to fix it yourself. I've sent a transmitter to Airtronics twice for repair and have gotten about a week turnaround time. Once was for a broken battery connector on the circuit board of the RDS8000, and the other was because the SD-10 won't work with the Real Flight simulator. BTW, I found out after $25 worth of shipping both ways that it isn't capable of working with any simulator because the voltages of the trainer port are different. The Airtronics tech could have just told me that had he known.

As for trading up or not, look at it like this. You can probably repair the transmitter you have and sell it for about $40. So the SD-10 package will cost you $320 total when you allow for the real world value of your radio. Or you could apply that money to a different radio in the same price range. The $300ish price slot is extremely competitive, so there are lots of good radios to choose from. If you believe the best value is in Airtronics, then go with it. If not, go a different route. I do realize you have receivers to deal with too, but they'll sell on the used market too.

abufletcher

From looking at it, it seems like the tricky bit would be to make sure that the dots of solder don't touch neighboring dots of solder and that's a matter of a fraction of a millimeter.

Not really an option for me since I live in Japan. There would absolutely zero market here for a used Airtronics Tx and trying to sell them in the US through something like eBay would be a non-starter. Making a switch between brands always involves some financial disadvantage. The trade-in for the SD-10GS is a good deal since I would be able to continue to use my four Airtronics Rx units. On the the other hand, if I bought the Futaba 8J (which would come with one Rx) and added another, that would take care of things short term.