ntsmith

Just a thought, but have you tried flying with the latest rx and the logger just to see if that can shine some light on the problem?

jmohn

Jim,

No offense but I did this exact same thing with the developer of the Spektrum system who lives in my town. We were able to show exactly what I stated earlier. It took several seconds for many of the receivers to reboot. We tested many (20+) receivers and several setups. I am glad you are happy with your Spektrum system. I wish I was too, but I can't afford to fly an unsafe system. I was quick to jump onto this system as I fly at many uncontroled fields and have had people walk up without checking frequencies and shoot me down. I was really excited about the Spektrum techonolgy, but unfortunately it has not been the best system for me.

jfetter

JMohn,

I was browsing this thread and am interested in your failures, I too was an early adopter of a Spektrum DX7 and now also fly a 9303 2.4GHz, both have been rock solid without a single hiccup. The reason I am curious is because you mention various batteries, various RX's but one commonality (I am assuming here), seems the transmitter is the same across all 4 failures, yes? Also, the terms "brown out" and "lock out" are being tossed around interchangeably but of course are quite different, one is a side effect of low voltage and the other low voltage or signal loss on either side. My question to you is have you ruled out your transmitter as the culprit by returning it to Spektrum?

I fly only electric planes and helis with most being 6S and a few 12S setups as well, all of them use BEC's (all high voltage and sized for the number of servos or hooked up in parallel to satisfy the current demand when more servos than supported are used), I do this because I am fully aware of the condition where the RX can in effect reboot due to low voltage. Truth is in that scenario you should be able to reproduce it, even Quique had this happen during a public demonstration flight (covered and explained by both Spektrum and his own site) and it was traced to the new hign amp-draw JR servos. So since this condition (low voltage) is easy to reproduce in the lab (you have the servos, RX and battery and can hook up on the ground at will) I am curious to know about the other half, the transmitter...

Jack

jmohn

Yes, the transmitter went back to Spektrum after the second crash to check it out. It was ruled out. All the batteries were Thunder Power packs. I could see the servos causing the problem too if they draw more than the receiver can handle. Two planes were running four servos on board (all HT) the other two were running 5 servos, all 322s.

If it was just a transmitter they would have switched it out and I would be fine with that. The re-boot is the issue and it's there and needs to be fixed, but it won't until the next gen comes out on the 9000 series. That leaves a lot of older receivers that can lock you out when they re-boot.

jfetter

Well, let's not spread any misinformation, if the RX loses power or reboots, it scans and re-acks the signal no differently than when turned on initially, I don't think there is anything that needs to be "fixed" there. As others have noted, my Spektrum RX's scan and lock on the TX channels within a few seconds when turned on and when put head-to-head with my new 9 channel JR, I don't notice any difference.

If the TX is also ruled out, how about commenting on how many others have had similar issues with Spektrum-based systems at your field? Also, it is feasible that there is something causing quite a lot of RF at your field, assuming all of your failures were the RX losing signal (not browning out and re-booting like many assume), does your field have a history of higher-than-usual crashes, perhaps on 72MHz even?

I am only trying to get to the root cause by ruling out other potential issues as I don't believe there is a design flaw with the Spektrum system. Keep in mind it may be new to us when the system reboots or the process it goes through to re-ack the TX channels but the Spektrum engineers planned this out as engineers do, thoroughly. I'm not saying there is no such thing as engineering mistakes but this system is flying in tens-of-thousands of planes and from the results at my field, the failure rate (due to crashes, "hits" and other radio issues) is lower than 72MHz systems...

Jack

ntsmith

This was why I had said use the rx and logger to see if light could be shined on the RF situation at the field.

ntsmith

One more idea to throw in the cauldron. Do you fly with a mobile phone in your pocket?
The only times I felt I have had a dodgy flight was when I had one in my pocket and on. I forgot all about that. After that instance I allways had turned it off and as I say have never had any probs.
As you say, you really do need to get a definative answer - and its got to be there somewhere. Probably staring you in the face.

jmohn

Jack,

If it takes a few seconds to "lock-on" or "re-bind" that's way too long if you are in-flight. A data logger might show me some in-flight issues, but they have been repeated on the ground, so I don't think it's critical. All I can say is that I have worked with one of the developers of the Spektrum system on this problem and he is aware of it and has tried to fix it. I know there are many people flying fine with this system and that's great, good for them and I hope they don't have any problems, but I have and won't anymore.

Also the first gen 9303 and 9000 receivers still have this problem so you may see a few seconds to bind or re-acquire the signal if you have to first gen receivers. If you have the second gen with the "quick connect" feature you will not see any hessitation when you loose power or "brown-out".


Jeff

mrfixit220

.Ok here’s what happens when you loose signal and it takes from 3-6 seconds to reboot and start to fly again. I had a very one sided conversation today on the phone with horizon about this situation. This has now happened to me more than once but this one angers me beyond words as I bent the crank badly on the g20 it went in so hard. The fact of the matter is they are stating its happening when you go below 3.2 volts for even 1ms. I was informed that they have no idea how we are going to use the plane so the digital servos that are supplied with the dx7 and the battery are ok. I was informed that a 100% fully charged battery in say in a flat spin where all surfaces are in play could drop below 3.2.volts. I was informed that we are responsible to check the battery each time we go up with a volt meter with the plane under load to see we are fully charged. Those of you that haven’t had it happen congratulations. I am not beating the product I actually embrace it as I for one can’t remember to put up a stick to save my life but....if people are having this happen with more frequency it needs to be discussed in a professional way so the less informed users understand what can and will happen. If they are working on a fix at least address it and I would gladly accept it. If there is no problem than stand up and state this and I again will accept it. But to allow it to go on without more of a public warning isn’t only wrong it’s dangerous. This pile of sticks went in from 100 feet or so at full speed. I could care less about a pile of sticks really it means nothing but the shame of it is were pushing 2.4 on everyone new to the sport so I think it is a good idea to address this correctly.

danny,please address my post or email me at [email protected]

jmohn

Oh there's a prlblem for sure, but it's our fault for not doing something? Come on and fix the problem or pull these off the market before someone gets hurt. I have never had a lock-out in my 20+ years of flying RC planes until I started using Spektrum. Sure I had glitches which on a 72 mghx system just made you loose the plane for a fraction of a second, but never a complete lock-out for 3+ seconds. Maybe it's time for my lawyer to get involved?

PacificNWSkyPilot

My Feedback: (19)

Lawyers, shmawyers.

Every radio system ever put out has limitations. If you didn't pay attention to them and accomodate them to the BEST of your abilities, you took your chances and you lost planes. If you're not supposed to drop below 3.2 volts, then use 5-cell packs and keep them charged up. What you're doing is running MINIMUM passable equipment with a radio that you've clearly been told needs better than 3.2 volts to run properly, you're probably upsizing your servos and power demands (flat spins), and you're expecting it to work perfectly. You KNOW the problem, you're using the basic batteries that were put in the factory box that a hundred forums here have clearly shown to be good only for low-demand flying, and you're being stubborn about it by not upsizing your power properly. Basically, you're at the field flying without a frequency pin, because that amounts to about the same thing. Only YOU'RE the other guy who is turning on the TX, how stupid is THAT? I think you should avoid paying out a little more for 6-Volt packs and hire that lawyer, now, THAT would just be the topping on this whole cake of redundant *#^&@**!!*# here. You'd lose, then you'd go away.

OR...if you can't handle this technology and your VCR is still sitting there flashing 12:00, go back to the regular old-style transmitters and pat each other on the back about how smart you are now. Then go pick up the pieces when your buddy turns his TX on.

There are no solutions being sought here, jmohn is just having his own personal b^tch session about Spektrums, which work great for everybody else I know, and I know a TON of others with them. He refuses to bear any accountability or try to find any reasonable solution, just talks about what HE thinks should be this or should be that, all the time talking about dangerous or unsafe things he does and he doesn't want to hear anything different. He could well be the posterboy for the degradation this hobby has suffered since the onset of the "NOW" generation, computers and all the rest that goes with it.

In the 30 years I have been flying, Spektrum is the best radio system that has ever come along, and it's only going to get better. Keep doing nothing while guys like this run their mouths with brains disengaged and maybe we won't have Spektrum after a while. Undoubtedly the techs are working to lower that lockout voltage and work faster resets in and other safeties. In the meantime, I'm not going to sit here and listen to this guy putting down the best system ever devised to date. He has no idea what it was like when a train counter, or supermarket door, or business radio in a grabage truck..... could shoot down a plane you had worked so hard on.

I'm leaving this thread, and unsubscribing from it because I admit, I can't stand it. This guy is an idiot.

Jim

airbusdrvr

I'm with you, Jim! There is always one in every club.

mrfixit220

before you leave the thread i am not him and by no means am i an idiot.i am not using the battery supplied with the flight pack. i am using a 2100 mah 7 volt 2c lipo.i am using a giants grade voltage regulator from fma set at 4.8 (actualy 5.0)the battery had 2 15 minutes of flight time from a fresh charge 2 hours before. at this point i cannot test the battery as it is now shorted from the crash. this issue is more than just a few.if you dont like what we are asking by all means unsubscribe as you obviously havent had an issue. as i explained i could care less about the plane its a bunch of wood. i dont want it to happen again and i am looking for better answers than what i was supplied with. just do a search and you will see plenty of threads stsrted and closed with people having the same problem. i am not looking to sue anyone but want a solution to the issue. should i start to use a redundant battery system if i want to flat spin or snap ? should i stuff a 3000 5 cell? we shouldnt have to unless this is what the actual solution is. all i want is answer. we have no issue or we are working on a solution. if its the first then i need to do a redundent battery as they do in a giant scale in my new 1/4 330.its a simple request.

seattle_helo

My Feedback: (1)

So even with a regulator set at 5v output you are somehow going below the 3.5v RX minimum? Are you flying super aggressive 3D? What's worrisome here is that even with a regulator this would still be an issue. The load must be incredibly high to drop your output voltage by so much. Or maybe the regulator is not sufficient.

nick

ricomari

I've been flying a DX7 only a few months and it's awesome! But I know new systems have growing pains, I want to know the good, the bad, and the ugly..........only way to learn. Sooooo, JMOHN bring it on![>:]

mrfixit220

"POWER FORCE" Voltage Regulator
Part Number: VRLI2




The "Power Force" is designed specifically for powering high current flight electronics (receivers and servos) in radio controlled aircraft. It can be used in sport, giant scale, and electric planes and helicopters. It is ideal for use in aircraft with dual radio systems. Outputs are user selectable, 5V or 6V. Extremely low dropout regulator maintains maximum 0.15V drop, even if the battery voltage decreases under full load (e.g. if battery outputs 4.8V, the VRLI2 outputs 4.65V minimum. The VRLI2 supplies up to 10A continuous current, sufficient for driving a plane-full of high torque and/or digital servos, as well as standard, micro, and mini servos. Status LEDs provide quick indication of battery condition. Includes on/off switch with failsafe operation and will not drain the battery when switch is off.


now, if i need i will eat my post but i read an additional set of guidelines dated may 07.


Posted: Thursday, May 31, 2007
Provider Name:
Issue:
Copyright: © 2007 Horizon Hobby, Inc.





Recommended Guidelines
Receiver Power System Requirements
With all radio installations it is vital the onboard power system provides adequate power of 4.5 volts or more without interruption to the receiver even when the system is fully loaded (servos at maximum flight loads). This becomes especially critical with giant scale models that utilize multiple high torque/ high current servos. Inadequate power systems that are unable to provide the necessary minimum voltage to the receiver during flight loads have become the number one cause of in flight failures. Some of the power system components that affect the ability to properly deliver adequate power include: the selected receiver battery pack (number of cells, capacity, cell type, state of charge), switch harness, battery leads, regulator (if used), power bus (if used).

While Spektrum’s receivers’ minimum operational voltage is 3.5 volts, it is highly recommended the system be tested per the guidelines below to a minimum acceptable voltage of 4.8 volts during ground testing. This will provide head room to compensate for battery discharging or if the actual flight loads are greater than the ground test loads.

should we then be using 6 volt flight batteries if the 4.8 volt threshold is this close ?(i was using a 2c 7volt 2100mha lipo) what is the best way to connect multiple batteries of the same mah to a single reciever? obviously the flight load will be significantly higher due to the load put on the control surfaces as suggested in the paragraph above.

sorry but i need to edit my post and add some stuff. after having time this evening i took the time to fully read my manual again. all 108 pages. after a long long lecture today from horizion i looked for this elucive section that explains proper voltage and set up in the manual. on page 102 of the manual in general information i found this :

Daily Flight Checks
1. Check the battery voltage on both the transmitter and the receiver battery packs. Do not fly below 9.0V on
the transmitter or below 4.7V on the receiver. To do so can crash your aircraft.
Note: When you check these batteries, ensure that you have the polarities correct on your
expanded scale voltmeter.
2. Check all hardware (linkages, screws, nuts, and bolts) prior to each day’s flight. Be sure that binding does
not occur and that all parts are properly secured.
3. Ensure that all surfaces are moving in the proper manner.
4. Perform a ground range check before each day’s flying session. The range check should be as follows:
• Do not extend the transmitter antenna at this time. Turn the transmitter “on.�
• Turn the model “on.�
• Slowly walk away from the model while moving the control surfaces. The aircraft should function
properly at a distance of 60–75 feet.
• For PCM Only: With the throttle fail-safe preset to idle, bring the throttle slightly above idle. Walk
away until the throttle drops to idle. This will be the distance of the range check.
5. Prior to starting your aircraft, turn off your transmitter, then turn it back on. Do this each time you start
your aircraft. If any critical switches are on without your knowledge, the transmitter alarm will warn you
at this time.
6. Check that all trim levers are in the proper location.
7. All servo pigtails and switch harness plugs should be secured in the receiver. Make sure that the switch
harness


no where does it help the newbies determine what battery to use based on the information provided. it does not indicate using the digital servos supplied with the supplied flight pack battery could exceed the recievers voltage threshold even be it for a ms. this manual supplies you with every type of set up mixing and programming but nothing on proper battery/servo combinations or even a mention of how to calculate load. am i asking or suggesting too much? maybe insted of bashing people for there extensive search for answers and calling them idiots use that 30 plus yeas of flying and help teach them or us your mistakes. i am one that has made at least 10 mistakes that my mentors say "we all did it at one time dont feel so bad" obviously you have made mistakes your selfs in those many years.your suggestion based on exp. says to throw bigger batteries at it to be safe. we have moved into a new era as you have suggested in tech. why have to throw a brick in to solve a problem that may be able to be rectified with software updates. maybe i am in way over my head but i think not after spending my day talking to every hi tech geek and rc radio professional i was able to get to in my 8 hour quest for answers. 90 % of all rc people use the green yellow orange red is dead method(battery indicator). we then need to educate people that this cannot be used any more.i have to admit i am actualy ashamed at myself for letting this happen as i am the biggest geek around.but in all my spectrum exp. i missed this one.....sorry for my rant

Ed

"I'm leaving this thread, and unsubscribing from it because I admit, I can't stand it. This guy is an idiot.

Jim "

Hey Jimbo ...... My patience has just about worn out with Jmohn also. He's got several threads on the same subject, right here on RCU. Makes you wonder.

I'm outta here ! [>:]

> GBJim

jmohn

Jim,

What ever makes you happy I am glad you so well spoken. I don't recall refering to you as an"idiot", but that's fine we understand some people are "gifted" and require "special" help. Your input or lack of it so far will not hurt the discussion. It's too bad you don't care if people may get injured by uncontrolled airplanes.

I have been nothing by honest with my posts and tried to convey the problems can causes as best as possible. Spektrum has a problem and needs to fix it. Why did they introduce the voltage protector for their receveirs? This was introduced for eliminate the problem I and many other have had. Here are some quotes from the Spektrum web site:

I see you offer a voltage protector (SPM1600). What is it, what's it or, and do I need one?
With certain electronic speed controllers, the BEC output is unable to supply enough power to operate high current draw digital servos. This can result in momentary loss of control[/color], especially during hard acceleration and when the battery pack is almost completely discharged. The voltage protector is a capacitor that is installed in any open channel in the receiver and it provides the power needed to maintain control during these periods. With most ESC's this is not a problem. The situation is most prevalent when running 4 cells (oval or 1/12-scale) with an ESC that has a low power output.
Back to Top

--note the second sentence: momentary loss of control. It only takes a moment to crash.

How long will the batteries last in the transmitter?
The included 1500 mAh transmitter battery offers nearly 6 hours of flight time in the DX7 transmitter.
Back to Top

--Same battery that crashed two of my planes on the first flight of the day, fully charged pack.

Can I use various brand of servos including digitals with the DX7?
Yes. All popular brands of three wire servos including digitals and even high current draw digital servos work with the DX7 system.

--I was using 322 servos so they should have been fine, nope.

Can I use digital and high current draw servos with the AR6000 receiver?
Yes. All types of common servos from the popular manufacturers are compatible with the DX6 system, including digital servos.

--same as above [&o]


Jeff

jfetter

JMohn,

I still think you are off-base by saying matter-of-fact that there is a problem with the Spektrum systems and way off-base by saying they need to be pulled from the market. I have seen perhaps 50 crashes in my years of RC with now-old fashioned 72Mhz systems, from heli's to small planes to turbine jets and never once did I say there is a design defect.

Truth is one could make a similar argument you are making against Spektrum against all of the manufacturers of 72Mhz systems and say they should have built the 72Mhz transmitters not to transmit a signal unless the frequency isn't in use (like Spektrum technology, bound by FCC regulations to do exactly that).

You might make the argument that they should have built 72Mhz RX's not to even recognize the transmitter unless it was "bound" to a Globally Unique identifier (GUID) with a 1-in-a-trillion chance of overlapping GUID's. After all that means someone can control someone elses airplane without knowing it potentially causing bodily injury.

One might even go so far as to argue they shouldn't have made 72Mhz equipment even work if the model number currently selected wasn't the correct one, often resulting in reveresed ailerons or other control surfaces that cause crashes and potential bodily injury.

All of these "defects" were simply tolerated for years and years because it was inherent in the design, part of the way they were made. Spektrum RX's take no longer to re-ack a lost signal due to brown-out or an out-of-range condition than they do when initially turned on, seems that is all one could ask for. Yes, engineers have found ways to optimize these systems like assuming the same 2 channels the RX had locked onto before the brown-out would be the same ones in use when it reboots and starting the channel scan there, making recovery as fast as possible but these are programming tweaks to an already well thought-out and designed system.

I am truley sad for your loss, I know the feeling and it sucks but I think your insistence there is a fatal flaw in the Spektrum design is wrong, especially given the thousands in-use daily across the worlds flying fields. Every system from cars to planes to household electronics has an operating range that if not met, will result in system shutdown/reboot/brown-out Spektrum included. The issue really is you have an ojbect in the air with the unstoppable force of gravity pulling it down at all times, if you lose control for any reason, the object is likely going to succomb to that force. Having a 2 second loss of control versus a 4 second loss of control is an issue but face facts, with all the system enhancements, GUID recognition, Model Match technology, increased range and processing speed there is still room for error and statistically, over-whelmingly so to the tune of perhaps 99.997%, the error is caused by us humans, not the electronics that repeat the same thing millions of times without error over their life...

Jack (JFetter)

tadawson

Oh, exactly like Multiplex does on 72 ? ? ? ?

- Tim

jerrygable

I believe that Spectrum may have already made a change which will greatly reduce the time it takes to reboot the system after a low voltage "brownout".

The following is an excerpt from page 22 of the DX6i user manual (the new 6 channel Spectrum transmitter that ships with the Blade 400):

Note: Receivers manufactured after July of 2007 offer a quick connect feature that reconnects immediately when recovering from a low voltage "brown out".

I had previously heard that the new JR921 receiver incorporated this "quick connect" feature, but this is the first reference I have seen in a Spectrum manual that addresses it (seemingly across the board on all receivers).

I do believe that some users have experienced crashes due to the time it has taken to reboot once the voltage drops too low (regardless of the cause of the voltage drop) and I am very happy to see that Spectrum has addressed this issue. My understanding is that the receiver now simply reconnects the two frequencies it was using prior to the low voltage dropout.

I do not know if receivers manufactured prior to July of 2007 can be updated to include the "quick connect" feature --- it would be great if they could be updated.

Hope this helps --- it sure makes me feel more comfortable.

krazyman

I lost my Cularis the other day when I lost control. I think the two story house with a steel roof blocked my signal. I am using the DX6/ar6000. I never did find my plane, it probably went into the Verde River, and floated down stream.

rino

My Feedback: (121)

Does anyone really know anything for sure about this new feature. I called HH today and they told me they didn't know what rx's would have it or what the release date would be. I would like to know.

jmohn

Yes the "Quick connect" feature will fix the problem (not a problem if you talk to Horizon). The new 9000 and 921 (the same receviers) do not re-boot and search for a signal if they loose power or get a brown-out. They just stay on the last bound channels and keep receiving. It's so quick you don't even see it happen. With the other Spektrum receivers you see some delay while the receiver tried to re-acquire the signal. It takes anywhere from less than a second to 15 seconds, depending on the recevier. At least that's what my tests have shown on over 15 receivers so far.

As long as your power supply is rock solid you will not have any issues with your Spektrum stuff, maybe, sometimes, not sure

Just fly Spektrum on your small stuff that you don't care about if it crashes and you'll be fine.

rino

My Feedback: (121)

I would just like to know when quick connect will be available for the different rxs.