stryker_20

My Feedback: (3)

I'd like to start a discussion regarding the two major spread spectrum players out there. I'm not interested in hearing why you like FAAST or DSM2. I want to hear from the real world users of their experiences. Number one regarding reliability. Number two, regarding any problems you've experienced or have seen at your field with either radio. I don't care what the latest hype from your buddy is regarding FAAST or DSM2, or what Futaba or JR have to say. I want to hear real life experiences. Has anyone experienced an unexplained crash that was absolutely without a doubt the radios fault (ie not I'll blame the radio because I neglected to charge my batteries, or loose connections or something like that, or bad battery, or bad voltage regulator, or improper binding or, well you get the picture?) I'm talking about a total radio link failure resulting in a loss of control/aircraft If so, what radio was used? Give us the conditions (hot, cold, wet, dry, how many pilots, etc.) I'm hard pressed to find someone that can really pin down an actual failure of either system that is unexplained. Everything I gather is user error and/or just plain ol'e neglect. The reason I'm inquiring about this is someone has told me of many many "unexplained" failures of DSM2 systems resulting in loss of aircraft. He personally experienced one himself, but rebuilt the plane, and flew it again and experienced the exact same thing. I question why people immediately blame the radio. If I experienced this I would have found the source of the problem before I flew again. I personally fly many models from small park flyers to large 33% aircraft and 1 turbine. I've never experienced a "hit" on my 2.4 JR9103. I personally think that each system has its pros and cons. Neither one being hands down superior to the other overall. What do yall think?

MikeL

My Feedback: (3)

You will never get what you're looking for. For one, brand loyalty colors many opinions. For another, "blame it on the radio" is a classic, time-tested way to maintain one's pride.

They each work very well. That's about as much as can be really said. It comes down to strictly personal preference and which offers features that work best for a particular person/application.

airbusdrvr

At the point we are with 2.4Ghz, this is like putting a stick in an ant hill. You will get ants swarming out. The radio question will not get answered. Why not just read the thousands of threads already on this subject.

XJet

Both DSM2 and FASST will work very well under the right circumstances.

The fact that there are many, many thousands of modellers who fly both systems every weekend without problems is proof of that.

However, neither (despite the claims of some manufacturers) is bullet-proof and the 2.4GHz band can be a very hostile place in some locations at some times.

Also, there are two aspects of any 2.4GHz system that need to be considered:

1. The design/theory.
This is the type of SS (direct-sequence, frequency-hopping or a hybrid of both).

2. The implementation.
This is the actual chips and software used by each manufacturer to implement their design.

DSM2 is a two-channel DSSS system that transmits on two virtual channels with in the 2.4GHz band. This provides a perfectly adequate level of resilience to the kind of interference likely to be encountered under most circumstances. That's their design and it's pretty sound.

As far as implementation goes Spektrum/JR have had a number of issues which have meant that the systems haven't always been faultless. A relatively high reboot voltage (and shipping with a 4.8V receiver pack) meant that lots of early adopters lost models. This (and other) issues have since been acknowledged and resoloved. That makes the DSM2 system robust and reliable. Even better, they've put a lot of effort into diagnostic and reporting functions so you can actually check and see how many dropouts/lockouts you had for peace of mind.

FASST is a hybrid FHSS/DSSS system that in theory, should be the most resilient to interference. It's a sound design that's been widely used outside the RC field.

As far as implementation goes FASST (like JR/Spectrum) has not been without its problems. However, the biggest problem is that (in the USA at least), there has been only a grudging acknowledgment of issues such as the ZGUID problem and there's still no real acknowledgment of the heat problems that appear to plague some of the FASST receivers when operated in high ambient temperatures.

So those tossing up between the two technologies have a bit of a tricky decision to make:

Do they go with the technically superior solution (in the form of FASST) but be stuck with a manufacturer that is slow or unwilling to acknowledge/fix major flaws in the implementation or do they go with a somewhat less sophisticated (but adequate) solution that is backed up by a manufacturer that is prepared to admit when they've stuffed up and who provides pretty rapid responses/fixes to those implementation issues?

It's a personal choice and (as I said right at the start of this post) there are many thousands of people who fly both systems every weekend without any issues at all.

stryker_20

My Feedback: (3)

I've spent the last month looking at the 10's of thousands of posts without any luck, so I thought I'd try to collect some peoples experiences in this post. I agree with both of the last posts. The blame the radio thing seems to be the best. I saw a post on youtube that immediately blamed the radio. They just walk up to the burning wreckage (jet) and say, "spektrum 2.4 radio lockout." Who's to argue with them? It was a maiden flight. Heck it could have been a disconnected elevator servo. The guy admits he could roll the aircraft. Doesn't sound like radio lockout to me. But it feels much better to blame the radio than to admit that I'm a neglectful builder and didn't secure something, didn't charge my batteries that lead to the demise of the aircraft.

victorzamora

It's most definitely easier to blame something other than yourself. I'm a Futaba user, always have been and don't really plan on switching. I just bought a 10CAP a couple of months ago, and am ecstatic with it. I've never had a glitch or a hiccup with the system. I've flown it with a 6014 Rx (the one infamous for heat issues), a 617, and a 606. I've flown it in 90* weather, and I've flown with it in 30* weather. I've flown it in electrics and glow planes. I'm just letting you know that so you can understand my bias. I also know people that have countless flights on a few Spektrum DX7's, a couple X9303's, and an XP9303 with a 2.4GHz module. I believe that, like 72MHz, all of the current radios are of such good quality it's personal preference. I think that the ZGUID issue was a result of carelessness, and am glad that they've since resolved that. I'm upset that Futaba hasn't publicly put any effort into figuring out the heat issues. I'm not saying they're not, I'm just saying I haven't heard of any. Spektrum/JR also was very good at keeping news of the initial problems a well-guarded secret.

If it helps, I decided to go with the 10C for a couple reasons. I had a 7C and needed a new radio for dual elevator capabilities. I decided that if I was going to move up to a new radio, it was going to be 2.4GHz. I also decided that I was moving up in channels and sticking to a first-tier brand (JR or Futaba). My budget kept me from anything above the X9303 and the 10C. I decided on the 10C because I wanted to buy a completely new radio. Why spend the money on a new radio if it's just the skeleton of a 4 year old radio with new guts? I mean, the 9303 has been around for a while.

My point is, don't let brand sway your decision. Both brands are more than sufficient for R/C and will remain so for years to come. I know it's not the answer you wanted...but it's as unbiased as I can get .

bruce88123

The ZGUID issue has been addressed and fixed for all that have taken the time to have their equipment sent in for repairs. The heat problems are relevant to one model of RX and the issue has been and is being addressed. Worthwhile corrections take time.

BuschBarber

My Feedback: (2)

I have two JR XP9303 Tx's. One has a 72Mhz Synthesizer RF module and the other has the Spektrum 2.4 RF module. I have two AR9000 Rx's and several AR6100 Rx's.

My first AR9000 Rx developed a non working Aux3 channel. the Hobby Shop replace it immediately. Both AR9000 Rx's needed to have the Capacitors secured with Hot Melt Glue when it was discovered that some Capacitors were vibrating and breaking the attachment points. It never happened to my Rx's, but I had the problem fixed anyway. One time, I had a problem ReBinding an AR9000 Rx that I previously had Bound. It turned out that I was trying to Bind near a large metal hangar. When I moved to a location away from the hangar. the Rx was able to Bind with no problems.

I have yet to have a crash with any of my Spektrum Rx's, however, I did have a Freaky incident, twice. I was flying my H9 P47-150, with an AR9000 that I had been flying, in that plane, for a year. One day, as I was flying Straight and Level, the plane unexpectedly rolled 180 degrees to Inverted. I rolled back to level, dropped the gear, and landed. I switched to another AR9000 and added a 36" cable to the one Satelite Rx. I flew another flight with no incident. On the next flight, it did the same thing, in the same way. This time, I replaced the Aileron servos (JR821) and the servo extensions. I have not had the problem since.

I love the Tx's and Rx's and just the freedom from Frequency Pins, RF noise, and Shootdowns. I highly recommend the system.

This is Real World Data and not hearsay. You can draw your own conclusions, but I believe I solved the problem and it was not the 2.4 system that failed.

ira d

I have not heard anything from Futaba on the heat issue last I heard was that
Futaba USA had contacted Futaba Japan and has yet to here back from them.

Also in your statement you said the issue has been and is being addressed I
would think it would be one or the other, Also there has been reported heat
issues on all the Futaba 2.4 receivers but the 6014 tops the list with the most
reports of failures.

hestvikauto

On all the futaba 2.4 recievers??

Now ,can you show me these reports please

ira d

If you follow all the posts on the the subject on all the forums not just RCU you
will find there have been reports of heat issues on all of the Futaba 2.4 receivers
and that any of them can shut down if they get a little too hot.

I have two 607's and they both have worked fine for almost a year but i'm kind
of parnoid of using them on really hot days like when it's over a 100 degrees
however the 607's seem to be the most heat tolerant of the bunch.

hestvikauto

Yes I read here and over at the other place and I can count in one hand the issues, I don’t even call them cases because there are no proof that heat causes anything.
This is a perfectly good example of how things and episodes can get out of hand and escalades into astronomical proportions.
I am no brand loyal and the last year I had had multiplex royal evo 9, Sanwa rd 8000, graupner mx 22, and currently I have Futaba 10 C.

Sometimes it looks likes there is a witch hunt at Futaba in these forums.

Well I am going to enjoy my futaba receivers for years to come and if people want to use the rest of their life worrying about this utterly bull, then that’s their choice.

DougV

I just don't get it, this is a hobby it's supposed to be fun, if people are afraid of using their own gear, then just sell it and move on to the next brand, that is what I did, and now all I fly is FASST.

Not a single issue for more than a year.
-Doug.

hestvikauto

Thanks

My point exactly, its called poisoned by the internet.

ww2birds

My Feedback: (14)

Well, here is one to ponder ... but first .. full disclosure!

I fly a bunch of the FASST gear and a DX-7. All of the big warbirds and jets on FASST, a lot of my other stuff (electrics, etc) on the DX7. Both work great.

Here is the question...

Which one "is" better and which one is "perceived" better?

Futaba is sticking with the frequency hopping system with the two built-in antennas, JR has all the extra satellite RXs and the glitch/fade counter.

The engineering/scientist view would be that if JR offers all that stuff, they must need it. A good engineer would never make a system more complex than it needed to be, and would conclude that Futaba is confident in their RF link and JR is not. This is believable since the Futaba approach of "real" spread spectrum is generally acknowledged to be superior from a pure RF link point of view, while the JR system was simpler to implement, and even if technically inferior, is demonstrably adequate for the task. I have to admit that it's entertaining to see the JR loyalists bragging about how many satellite RXs they could festoon their airplanes with.

The JR marketing guys (who, IMHO are really really good at their jobs!), take this multiple RX thing and turn it around with their ad about "I'd never trust my jet to a radio with only one RX!" and try to get the customer to draw the opposite conclusion that the techies would make. I also got a kick out of how quickly they responded to the complaints about heat sensitivity on the Fut 2.4 RXs. Futaba has yet to make any reasonable response, and JR already has ads out making fun of them. Humorous for sure.

As far as I can tell, we don't have any reliable or quantitative basis for comparing the "solidity" of the RF links of the two systems beyond anecdotal observations (like mine above .. they both work fine in practice), but it is interesting to compare/contrast the marketing and engineering world views.

Dave

BuschBarber

My Feedback: (2)

I do not have a problem with Futaba Fasst. I was Futaba for 30 years. I only switched to JR because I happened upon an XP9303. I liked the features better than my Futaba 9CAP. When Spektrum introduced the 2.4 module for the XP9303, that sealed the deal.. I think if the 9CAP had given me 9 proportional channels and subsequently a 2.4 module that gave me 9 channels, I would have stayed with Futaba.

It was all a matter of timing.

I am sure that the Futaba 10. 12, and 14 Ch radios are fine.

I do like the PC USB interface for my XP9303. I can copy all my model memories to my PC, Edit them there, print them out, and copy them back to the Tx. I believe this is also a way, in the future, to Flash Upgrade the Tx.

ira d

I beg to differ when you say there is no proof that heat causes anything, Many folks
have heat tested their Futaba 2.4 receivers and have found that they are indeed more
sensitive to heat than other receivers that are on the market.

I also find it odd that Futaba has kept quiet on the subject I would think that if there
was no fact to the heat issue that Futaba would do some testing on the issue and
display the results for all to see and put to bed the subject once and for all because
i'm sure Futaba could be selling more radios if they didnt have this subject hanging
over them.

hestvikauto

I totally respect that we have different opinions.

But I must be completely blind; because I have not seen "many" test reports from fellow modelers claiming there is a problem, a few yes, but not "many".
Also I can’t tell how accurate the tests was and if it’s correct, I really don’t know because I was not there and if I where there, I would not be competent to tell anyway.
I have also seen a big test report claiming heat is not a problem for the 6014 receiver.

Just to put it on the edge for fun, if 10 people say to ford there is a problem with their brakes, do you think there will be a public statement from them telling they have a problem with many thousand of their cars, just because 10 people say so? Does it make it an issue that a few have a problem?
Of course Futaba is gigantic as a company, but tiny compared to ford �

Well, as I said earlier, I am not poisoned by the Internet so I will keep enjoying all my different radio system and have fun, and if I where to have a heat problem I surely will send it in on the warranty and not tell the whole world that I think they have some issues I demand ansered.

Cheers

XJet

I think it depends on where you live and in what circles you move.

Certainly there have been a good number of heat-related issues reported and documented in hotter parts of the USA during the past summer. Futaba themselves have tacitly acknowledged that there could be heat issues and as a result have issued advisories that their 2.4GHz receivers should *NOT* be wrapped in foam (which is a heat insulator).

There have been numerous independent, well-documented and 100% repeatable examples of the heat issue, including one that used infra-red imaging to show exactly where in the receiver the heat-build-up occurs and the magnitude of the problem.

Do you have a link for that?

But if you could repeatably demonstrate that Ford's brakes fail when exposed to summer temperatures you'd have a case and that's exactly the situation with Futaba's receivers. Futaba's sole response has been to suggest different mounting methods and to effectively say "don't let them get that hot" which is rather hard to do when you want to fly in the middle of an Arizona summer.

ira d

X jet

You make some excellent points.

ira d

I had 2 out of 2 6014's go bad. I am not using them till I see some more results, with people using the 6014's. I know a lot of people swear by there FASST systems and a majority of them are using primarily 607, 617's.

I am running a TM-7 in a 9C and a TM-14 in a 12Z. I never had a problem with the 7ch setup up. I bought both when they first came out. The TM-14 on Jan 08-08. I don't remember when I got [QUOTE]

Just saw this today over on another forum it's on the FAAST forum last page post
#1181 of the flying giant forum.