fasteststang

My Feedback: (1)

Good points however you are comparing apples to oranges.

1. Your cell phone from 5 years ago was not advertised as having a "bullet proof" connection as the Spektrum DSM2 modulation was.

2. Back in 1997 my in laws had a 1991 Ford F150 that burned up due to a faulty ignition switch. Many people had the same problem and Ford replaced many 5+ year old trucks and recalled and fixed many thousands if them.

3. If my 3 year old iPod caused my TV to crash every once in a while, after 3 tv's I'd want Apple to fix the glitch in the iPod. I think that is reasonable since I never asked them to replace the 3 TV's that crashed due to their glitch.

Your right that when you buy technology, you just have to accept that it will very quickly be outdated. I'm good with that. But if the product is faulty then the company should fix the problem.

Rob2160

You also make some very good points.

I don't know if you could say the actual DSM2 Protocol is faulty. I have been using it without a glitch for many many years. Is it perfect? No, is DSMX Better, Yes! I flew 29Mhz AM and 40 Mhz FM for many years and with that technology you always ran the risk of same channel interference.. I guess when DSM2 was first released it was a significant improvement.

Sure, the early receivers had a higher threshold for brownouts but if you had good batteries many people never had an issue..

The RX equipment worked if you powered it correctly. Later updates made the RX's more forgiving to low voltages and faster to reconnect.

Of course, I totally understand that in any product, some people will get faulty units that simply don't work.. If 50% of Spektrum users experienced crashes and lost aircraft in the early days the company would not exist today.. Even if there were a large number of problems, I imagine It was actually a very small percentage of Spektrum owners who had problems.

I personally have 3 DSM2 only transmitters with zero issues in many years of flying on numerous different aircraft and helicopters. With that track record I will never accept the DSM2 system is flawed.. it works great for me. (I totally agree DSMX and any frequency hopping system is better)

When I was a cop, we used Glock pistols. there were over 16,000 of them issued to the NSW Police Force. Mine was flawless, perfect and never jammed or misfired once in 8 years and more than 2000 rounds fired..

Other people I knew had lots of problems, jams, broken springs, failed firing pins. etc.. variations and individual faulty items can happen with any product.

Dave McDonald

My Feedback: (19)

No problem Rob!

Like you, I'm also pretty pedantic (ok, I had to look that word up) about my radios.

The DX7 and the 6110e receivers were my first experience with 2.4 GHz spread spectrum technology, and I did some extensive testing with them before I began to trust that itty bitty receiver and those whiskers they called antennas. Long story short (ok, not very pedantic), all of the 6110e receivers were progressively tested at farther and farther distances, and higher and higher altitudes, first in foamies, then later in glow powered planes. I was trying to find the in-flight range limit, and failed. The 6110e receivers were even flown in some high speed combat flying wings, and a piped 46 glow powered Diamond Dust, and they all worked perfectly every time.

To date, I have never had a Spektrum lockout with a glow powered plane, or even a Bind-N-Fly plane. But I've had at least six unexplained lockouts in small electric planes with these same 6110e receivers. That's what really bothers me. How could these same receivers lockout at distances of less than 100 feet when they had been working perfectly in every glow powered plane I ever flew them in, including a Diamond Dust?

* The lockouts were not a range problem. They all occurred within 100 feet of the transmitter, with most occurring a lot closer.
* All of the 6110e receivers had the latest Quick-Connect firmware, so a brief brownout would have restored control nearly instantly.
* In the crashes where the battery stayed plugged in, the receiver light was on steady, indicating no brownout had occurred.
* The pre-programmed failsafe did not activate, yet worked perfectly again after rebooting the receiver power.
* The only way to end the lockout was by rebooting the receiver power. Cycling the transmitter had no affect.
* The most recent lockout was with a JR 9303 transmitter and a Spektrum DM9 module, with an Orange 610 receiver in a small electric balsa plane. So the lockouts are not confined to a DX7 and the 6110e receivers, even though they have still been confined to electric planes.

The last item is what scares me the most, and has permanently scarred my faith in Spektrum DSM2. I still have 29 planes being flown on DSM2, but they are all either inexpensive/expendable, or crash-resistant, or Bind-N-Fly planes. Since selling all of the 6110e receivers the number of lockouts has been drastically reduced, but not eliminated. Therefore the pedantic in me won't let me use DSM2 in the planes that I value, but the pedantic trait still wants to know why the lockouts occurred in the first place.

In the end, Spektrum dropped DSM2 and went to DSMX. It was a very smart move. You rarely if ever hear about any lockout/brownout stories about DSMX, so this thread has become a mute point.

Rob2160

LOL. I thought I was the only one who was so pedantic.. Enjoyed reading about your tests and I totally understand the ongoing "curiosity" about what caused the lockouts in the first place..

Yep, its a mystery to me also hat they work fine in Glow and BNF aircraft but lock up on the other aircraft.

To be honest I have never used the 6110e receivers. Mine are mainly, AR500s, AR600s, AR8000s and AR6200s, all which have never let me down.

I also totally understand your caution with DSM2, sounds like practical wisdom to me. Though I have never personally had an issue with DSM2, I only use my DSM2 transmitters in the smaller Ultra micro aircraft and small Blade (E-flite) Helis. The larger planes and 450/550 Helis are all on my DSMX radios with DSMX receivers.

After 30 years of flying with a 1 meter antenna in front of me, I just couldn't take the 2.4 Ghz radios seriously at first glance, but now I respect them immensely.

fasteststang

My Feedback: (1)

I admit it. I had to look up pedantic too.

Gary you are right, it is kind of a mute point. I just believe that a very real problem existed with the DSM2 radios since the brownout/lockout scenario has plagued so many. I also concour that many more people didn't have any problems with DSM2. But that doesn't lessen the disappointment that we who have lost planes due to these gremlins feel. When I sent my radio back to Horizon hobby, they said they found nothing wrong with my radio. Hence my frustration because there clearly is something wrong. Maybe all the hardware is good, but there is definitely an issue in the software. If they had just done a DSMX upgrade for free I would have the confidence to continue using my old DX7, however I do not trust that the lockout won't happen again. There for I will be selling my dx7 and buying something I can trust. Hey does anyone wat to buy a used dx7? Just got it back from Horizon with a clean bill of health.... No takers? Huh?

Ok sorry for the sarcasm, just the easiest way to relate my distrust with a radio I paid a lot of money for. Thank you Gary and Rob for insight, I have enjoyed conversing you guys on this thread.

Rob2160

I totally and completely understand. I imagine if I had lost several aircraft using DSM2 equipment (and was unable to pendantically find the cause) I would be the most vocal person here and I wouldn't leave Horizon alone until I got a satisfactory answer.

I also understand not trusting a radio.. If I ever had a crash due to lockout I would never be able to trust that radio again..

Only once in 3 years of flying with 2.4 Ghz I felt like I had lost control of my Heli for a fraction of a second, and I thought it was a radio or servo glitch.

I still don't know exactly what happened. But after this incident I tested the Transmitter for hours on the bench, literally about 4 full battery cycles and several real world range tests before I flew with it again.. The radio and this helicopter have had hundreds of flights since without any problems.. I have attached a vid of the incident. the Heli dives forward by itself at 0.11 just as it passes the tree and almost hit the ground but luckily responded immediately to my correction. (Futaba 8FG)

http://www.youtube.com/watch?v=LP18XIYmh8g

on_your_six

My Feedback: (11)

Any talk about how the antenna is oriented? If you are pointing the antenna directly at the plane, you are not going to get good signal. The 2.4 antenna should be pointed straight up or at 90 degrees to the plane's path. The power radiated is in the rough shape of an apple. Very little power at either pole of the apple.

Just saying.

mr.snaproll

My Feedback: (38)

I've been in this hobby for 22 years and JR(now JR and Spectrum) have always had problems. When a problem is brought to there attention they would always come up with an excuse and or blame the operator. After many people lose planes they eventualy take care of the problem, look how long they took to go from DSM2 to DSMX. I hav'nt heard anything bad about DSMX so far, but when or if there is a problem they need to man up and take care of the problem right away. This is why I don't use there equipment.

Rob2160

Definitely could be a factor in some situations

Dave McDonald

My Feedback: (19)

The direct answer to your question is no, the antenna was not pointed at the plane when any of the lockouts occurred.

In my case the lockouts occurred at distances of less than 100 feet where the transmitter antenna orientation would have no effect. These same receivers had been working perfectly in glow planes at distances of over half a mile with the antenna intentionally pointed at the plane.

AndyKunz

Most of my most cherished planes (sentimental value), to me of great value, fly on DSM2 receivers. I have no need to upgrade them to DSMX. They are fine - even the original AR7000 and AR6100 (with updated code) are still in use.

Andy

SkidMan

My Feedback: (17)

I always recommend that people verify their RF data using a $25 Spektrum data logger or telemetry.

You can use the data logger whenever you do range checks, after flights where you suspect a problem occurred, or even after a crash as long as the receiver still has power (Provided the receiver model has a data port). The data logger doesn't even need to fly. You can share one between friends.

DSM2 and DSMX are so fault tolerant and fault recoverable that you may never know that you are operating at the edge - although a thorough range check can turn up most problems.

Dave McDonald

My Feedback: (19)

Now you have a reason to worry that someone might be more pedantic than you.



I would still like to know the answer about why the lockouts happened. At this point I tend to believe there is a flaw in the DSM2 software or hardware that can cause the system to totally lockup under certain, but rarely encountered conditions. I have never been able to intentionally re-create a lockout, and that also bothers me. It would make me feel better if the 6110e were the only DSM2 receivers that were flawed, but the lockout with the 9303/DM9 transmitter and the Orange 610 receiver shot down that theory. So now I look at DSM2 as a ticking time-bomb, and the ticking-time bomb syndrome drove me away from Spektrum and into Futaba FASST. After four years of flying FASST, it has been absolutely flawless, even in electric foamies. Now I finally know what it feels like to have total faith in the radio system, just like the DSM2 guys who have had four years of flawless performance.



I've been flying RC planes since 1969, and the first 40 was with a 1 meter antenna on both the transmitter and the receiver. LIke you when the 2.4 GHZ radios came out, I looked at them as toys. It took awhile to trust them, and it took even longer to realize they worked better than the old 27 MHz, 72 MHz, and 50 MHz radios I had been using for all of those years in the past. Despite the lockout problems I have experienced with the DSM2 receivers, I'm not willing to give them up......which is why I still have 29 planes being flown on DSM2. But the valuable planes are on FASST until something happens that scars my trust in that system.

Dave McDonald

My Feedback: (19)

Ok, I feel better now. I'd never even heard of the word pedantic until Rob's post.


I have enjoyed this conversation too.

But I'm still trying to figure out who this Gary guy is.

Dave McDonald

My Feedback: (19)

You trust those DSM2 receivers because they have earned your trust over the years with flawless performance.
I wish I could say the same thing.

At this point, all I want to know is the technical reason for the lockouts.

Since you work for Spektrum, you are in a position to know why my 6110e receivers locked out.
But since you work for Spektrum, you might not be allowed to tell me.

AndyKunz

Actually, I trust them because I know what's going on inside DSM2. I understand your need to have "earned trust" in a product, but they have my trust because I understand the engineering behind them.

I don't know why you're having such bad luck. I do know why I'm not, though - I follow the "best practices" that Horizon has put forward since the beginning.

Andy

davidhand

I have a Spektrum DX7. Some time ago now two or three times when going to fly I looked down at my transmitter and the screen was totally blank. I switched everything off started over and everything worked fine. Then on another occasion I looked down at my screen when about to take off and the screen was upside down. I showed it to several people who were standing around and they were all in disbelief. All agreed I should "send it in".
About a week or so after sending it in I got a call from the tech working on it, I explained the problem and he said that was caused by a static surge when I switched on and was not a cause for concern. I said OK but as you have the transmitter now why not go ahead and upgrade it to DSMX. He said he could do that but it was unnecessary for sport flying and I would be wasting $75. So he sent it back as it was, since then I have been using a DX6i as I no longer trust the DX7.

AndyKunz

The display operation does not affect flying. What happens is that the display does not initialize completely sometimes; this is something that many LCD products will encounter. It can be affected by temperature, humidity, vibration, static, and many other environmental issues.

When we design our radios, they are segmented so that failures of one portion do not affect the others. The display is a monitor; data only goes out to it, and if it doesn't do anything with it (it could be totally removed) it wouldn't affect flight safety. The user interface is implemented the same way. If it gets stuck in an infinite loop and you can't do anything, the RF will continue to be generated based upon the inputs coming in.

Andy

fragile

Here is your answer: http://www.youtube.com/watch?v=FazZH...eature=related

Dave McDonald

My Feedback: (19)

If you have that much engineering knowledge of DSM2 technology, then you also know why the 6110e receivers locked out. Can you at least give me a hint?


So what you're saying is that I screwed up the radio installation of six different electric foamies, and the 6110e lockouts are entirely my fault.

This is exactly the type of technical support that drove me away from Spektrum and into Futaba FASST.

AndyKunz

Dave,

I'm glad you're happy with your choice. I'm happy with mine. I chose Spektrum long before coming to work here, based on the technical documentation provided as well as working for an RF company.

As you know, it's virtually impossible to do a post-mortem on an event that occurred long ago. I don't know the details of what you did, and without the ability to reconstruct the occurrence it's impossible to arrive at a solid explanation.

The problem is not some inherent fault in DSM2. If it were, I would have experienced the same issues you had. Based upon your "small electrics" comment, it seems logical that you would have made some of the common mistakes that others have made. I don't claim to be infallible, nor do I claim any technology is perfect, but I know that there's no way Spektrum would have become the biggest player on the field if we were selling junk. The market is very good about ensuring that doesn't happen.

Andy

gsmarino2000

My Feedback: (2)

I have literally hundreds of flights on DSM2 with no issues. If you add my flying buddies to it, I'm sure its thousands of flights. My newer planes are DSMX, but I don't have any issues continuing to fly DSM2 on my older planes. Our club is mostly JR/Spektrum and Futaba on 2.4Ghz and some Hitec. A few diehards running 72Mhz. Very few radio failures of any kind, but where there are issues my perception is that they are mostly operator / setup issues.

Greg

jester_s1

I'd actually have to disagree with you, Andy. The market is not at all good about putting companies who make shoddy products out of business. HobbyKing is proof of that, and look at how FrSky and Turnigy radios are flying off the shelves. Spektrum should have gone bankrupt in its first year because of all the problems people had with brownouts and other unexplained crashes, but the RC buying public made them a huge success. A huge marketing campaign and the convenience of BnF aircraft made that happen despite the company's products. Even when the Dx8 came out I saw a couple of threads about totally unexplained crashes, and have seen many more about Dx7 and Dx6 radios that were being run on 6v packs by people who had been in the hobby long enough to know what they were doing. After a few years reading these threads, I don't believe there is a problem with Spektrum's design; I believe there is a problem with Spektrum's quality control and product testing. I'll grant that the number of threads about unexplained Spektrum crashes has gone down in the last year, so maybe Spektrum finally has its act together ('bout time!), but to unleash all the problems on the RC community that they did in the initial release of Spektrum radios is unforgiveable. I fly Airtronics and have only seen one issue with their radios that was fixed at the factory very quickly, as in within a couple of months of the first reports showing up here on RCU. Futaba users had a similar experience with the heat issue being fixed very quickly and not coming back. Why other companies can do that and Spektrum can't is beyond me, but maybe that's what it takes to get the product out to market the fastest,

Rob2160

I hear you Andy and my own personal experience with DSM2 has also been flawless..

But it is possible there are faulty receivers, that can lock up or fail simply due to a poor component?, completely unrelated to whether the protocol is DSM2 or otherwise? Perhaps there was simply a bad batch of them (like the gimbals in the first DX8's)

This vid shows my Futaba 14SG had a flaw when new, (loose pots in gimbals) and there was definitely a software glitch on one power up, when channel 6 deflected fully to one side and would not respond to anything.. Turning off and on again cleared it and that lock up never happened again..

AndyKunz

It's possible that he had bad units, that goes back to my "infallibility" comment.

Andy