2.4 problems
 

Okay, so here is a little background. I only keep 4 models flying at once all on a DX-7. 2 ar7000's and 2 ar6200's all with the new firmware. Recently, i started having problems with my 50cc gasser that has well over 20gallons (about 16 on spectrum) run through it. Two times in an accumulation of about 1.5hours of flight time i had what apeared to be a minor lock out. There was no change of engine rpm and it is unclear weather i lost all control or not. However, the alerions felt very slugish and or uncontrollable for less than a second. Hard to tell as it lasted no more than a second. My first reaction was voltage drop but the receivers had a solid light suggesting that there wasn't a brownout. My next thought was a servo going bad on the left aileron. It can be on and off very sluggish, and often stutters when the wing is bumped or moved. I haven't gotten a new servo yet but now me leading theory may not be correct.
This weekend i drove up to my parents cabin in Flagstaff Arizona. I keep a tower trainer up here that has 2 or 3 gallons on it, all spectrum, with no problems. I takeoff and land right off the access road and fly over a huge open field behind the house. Yesterday i put 45 minutes of flight time on the plane. However weird things started happening today. First, i barely touched the low end trying the get a better idle. On the first flight i had a intermediate engine blurp, it sounded like it completely died and restarted. It didn't appear to loose any control, however i was flying around 400 to 500ft with a trainer so it was hard to tell. I brushed it off and flew around for another 5 minutes and the engine died. Again, no signal losses where apparent. My first thought was the low end that I touched earlier. I set the low end back to where it was before and went back into the air. 5 minutes in, i lost the signal and this time I am sure. The plane banked right and the engine died. Got the signal back and laded safely. I realize that the way the plane is bound the engine is at the off position and the ailerons level. I have to add a little left trim to keep it level in flight which explains why it banks to the right when i loost the signal. Again, checked for voltage brownouts but the lights were solid.
Now, i am not concerned about a little POS trainer, but I am concerned about the 3 other aircraft i have which total around $5000 in investments. What is going on here. It has been raining in flagstaff heavily but could a little humidity really cause this plane to have problems. Could the 50cc wing servo really be going bad and the relationship between these two incidents just be a coincidence. My 30size electric helicopter has had no signal problems. I would send the radio back but fear they will find nothing wrong. The radio is only two years old. Was dropped once but sent back for repair. That indecent was almost a 1 1/2 years ago. I keep the radio in a case with foam padding.
Any thoughts would be greatly appreciated
Thanks
Cameron

RE: 2.4 problems
 

It is important to review the binding instructions in your Spread Spectrum radio manual. When you first get your radio you must bind your receiver. In particular it is important with SPEKTRUM receivers that the binding plug be inserted into the radio receiver battery port or with the new version receivers, into the BATT/DATA port. You will then plug your power source into any unused port on the receiver. The alternate way is to use the manufacturer’s supplied switch/charge receptacle switch assembly. Binding must first be done when you first setup your model with a new Spread Spectrum receiver. It is perhaps even more important that you rebind again after you have set-up your plane and before your first flight. This will ensure the fail-safe settings bring the throttle to idle. Depending on your manufacturers’ model of radio, it may also enable the fail-safe controls to go to neutral and or the last commanded position in the event of a loss of signal. Any time you get into a menu, i.e.. to adjust end points, exponential, mixes, sub trims, you must rebind the receiver. Merely using the trim buttons in a normal fashion has no effect on binding. Please check and review your manual on this important item.


This is being circulated up here in Canada, unknown glitching, unexplained issues etc.......

RE: 2.4 problems
 

Please tell us which manual states this. We all know about the throttle/failsafe reason, but please explain why we must rebind "anytime you get into a menu..." Don't tell us that it is a "good idea" either, as many have. Thanks.

Kurt

RE: 2.4 problems
 

Binding isn't the problem here, the problem is i have had 16gallons running spectrum on my 50cc cap without a problem. I haven't changed anything. Same with the the trainer. over 2 gallons no incidents until now.

RE: 2.4 problems
 

it seams the most critical parts on the spectrum gear is binding and battery power. Cambo, what rx batteries are you using ? are you using a seperate ignition battery ? how old and in what condition are the rx batteries ?

RE: 2.4 problems
 

The cap went 18 gallons on 2 6cell 1500 nimh. Those started going bad. Recently i switched to a single 2S a123 with 2 on/off switches that has done fantastic for the last two gallons.
The trainer has always run 4cell nicd and recently switched to a 6cell nimh.
I haven't bound with the new batteries but can't imagen that changing anything.

I have a theory here. What if my 50cc cap actually just has a servo going bad. Under some loads it simply doesn't have the power creating a slow or lagging turn since only one servo would be moving, which is what I felt it was doing. Now, maybe the trainer has had lockouts before. The only difference being, i did work on it this weekend (repaired a week rudder) that caused me to move stuff and change the trim away from where it use to fly well. Now i am actually noticing them. Could it be possible that the HIGH humidity simply amplified a problem i hadn't already addressed and or didn't realize?

RE: 2.4 problems
 

Cameron,

I hope you have tested your receivers for properly functioning low voltage indicators. Don't assume they are present but test and confirm they are working. If you have, then from what you have written your battery packs shouldn't be a problem.

You seem to have a suspicion your transmitter may be at fault. While a number of things can give the impression that your plane has gone into failsafe, there is no reason you should have any doubt if that is the case for those planes using the AR7000 with the latest firmware. The newest AR7000 supports the Spektrum Flight Log. If you don't have one, you should get one.

There is the possibility that with much use and having been dropped, the transmitter may have developed a loose connection. I would ground check an aircraft that has an AR7000. Gently shake the transmitter while doing the ground check. If the plane goes into failsafe, the problem is most likely the transmitter. If you have an expendable aircraft, install an AR7000 that supports the Flight Log. Check it out the ground and then in the air. If you truly have a failsafe situation, the Flight Log will confirm it.

Allan

RE: 2.4 problems
 

I believe you are misinformed about the need to rebind after any menu changes have been made. I welcome any comments on this since this appears to be a debateable position and it would be very nice to have this stated once and for all by Spectrum. When binding this insures that that RX will accept any and all commands from that TX since they now share a particular code. Simply by making changes to that controls has nothing to do with the code. Therefore these changes will be accepted by RX. Naturally I can be wrong about this but think not and would as I said welcome any info from Spectrum on this.

RE: 2.4 problems
 

Allan
Currently all receivers are up to date. All were sent back for the updates. I do believe one is a newer ar7000 but i would have to check. All have been checked for the LV software. As a matter of fact, that was the first thing i checked upon opening the boxes

I don't currently have a flight logger but may look into getting one.

Cameron

RE: 2.4 problems
 

Also, that being said. I am almost %100 sure the trainer incidents were signal loss related. Turning the transmitter off, the way i have the fail safe set, would replicate exactly what the plane did in the air. Why I had nearly 45 minutes of flight time on the plane the day before with ZERO incidents is beyond me. What is also weird is the trainer incidents occurred within a 10 minute time table. What sucks is i am not sure if there is a relationship between these two airplanes. When the cap had its "glitches" it happened so fast that i wasn't able to tell if the plane just lost one aileron for a split second or if i lost control of the entire plane. These two incidents happened within 4 flights, over a span of about a week, with nearly 1.5 hours of flight time apart from each incident. The second incident did appear to be a little longer lasting than the first. What is even stranger is I put nearly 40 minutes of flight time on my 30 size e-heli between the two cap 50cc incidents without a problem. I might be resurrecting an old plane to test this. I really, really, don't want to loose one of these models.

Cameron

RE: 2.4 problems
 

So here is what i am going to do. Since i don't want to risk any of the planes i have in phoenix i am resurrecting an old duraplane and pulling the engine from my hellcat. If there is a problem with the radio I will find it. I am going to test every receiver i have in phoenix on the plane. Hopefully i will find that this is just a coincidence and the relatively unused receiver on the trainer is bad. I am going to see if any other club members have the data logger
Will keep you informed

RE: 2.4 problems
 

Hear, hear!

Kurt

RE: 2.4 problems
 

My experience with my spekrum is: I have one Rx (ar6200) that is sensitive to installation or has minimum range. In some installations it is OK, in others it will barely pass range check. It works normally most of the time but every once in a while it will go into fail safe. Horizon says nothing is wrong with it. It is now used only in my foamy. My other 9 Rxs have given no problems, even on 4.8 volts.

My gassers will pound servos to an early grave. The vibration will wear out the pots, making the servos weak around center. I would think that 20 gallons is more than enough flying time to wear out a servos pot. See if you can hold your aileron servos at center while moving the stick. I'll bet its time to repair or replace servos.

Jerry

RE: 2.4 problems
 

Jerry,
see that is what i was thinking. That servo is so week that it takes little force to hold the control surface in place. Thats why I think it may be just the servo on the 50cc. It tends to fluctuate in strength, mostly at idle. Both times it appeared that my "lockouts" where at idle which could very well have been just a servo problem.
Cameron

RE: 2.4 problems
 

So i just got ahold of a cermark sukio powered by a spe26cc 2 stroke. I stuck a spare ar6200 in the airplane that had several flights problem free however the receiver had a bad history in my 50cc cap. Losing the signal twice almost leading to a crash. I changed out to the ar7000 and all was good until the problem above. Still not determined if it was the servo or not.
Today, I had the entire electrical system with 2 switches completely shut down multiple times, always with the engine running. I could not get the signal back unless both switches where turned off and back on. ***? I don't know what this means. Even more puzzling was the satellite receiver's led was still lit while the main one was off. ????????????? Am i just plagued with demons here, or is something going very wrong? I flew my helicopter for 2 quick flights today, same transmitter, ar7000, no problems.

I am just so confused

Edit: Also with the engine off i could not replicate this problem. I walked around the plane with the bind button held down and lightly shacked the transmitter thinking that there was a loose connection. Again, nothing happened.

RE: 2.4 problems
 

cambo, you dont think this happening has anything to do with running your rx batteries down. i did notice in your first post you mentioned something like 1.5 hours flight time. if this is correct you are asking for troubles as no rx battery set ups last this long without a top up charge . i wonder if you check your receiver battery power under load before every flight ? there is allways a reason for something going wrong and most of the time its the guy who doesn,t take care of his model in good set ups and quality assured battery testing before he takes to the sky,s. lets just blame it all on the poor radio as usual.

RE: 2.4 problems
 

i would buy one, it will only work on the AR7000 on up or receivers that have the data port. It may be satellite position, or maybe one of the whisker antenna(e) is broken

RE: 2.4 problems
 

It is unlikely that the rx batteries are being run down. Every-time this happens the lights are solid, not beeping, and i do have the new software. My cap has two 2s a123 packs with two switches. I do mostly pattern and light 3d and the servos are mostly high-torque standards so the system is not taxed that hard. I do a voltage check after each flight and have a very good idea of how much flight time i could safley get on each plane.

My main concern is what happened yesterday. How could i completely loose the signal to the plane (again, BCAM gasoline 26cc running each time) and not get it back. Also, the satellite RX LED was still lit while the main one was off? This is just very strange.

In the simplest terms this is what happens to the su 31
Two switches are on
Transmitter is on
Satellite LED is lit
Main RX LED is off
Servos have no power, behave when i move them as if they are off
Signal can only be reacquired by turning both RX switches off and on

RE: 2.4 problems
 

Does Spektrum have a problem? I see a lot of talk here on RCU about problems with Spektrum Radios, real or imagined. The guys in my club are all fearful of making a change to 2.4 Ghz equipment due to the bad press this equipment is getting, especially here on RCU! I have an Airtronics RDS8000 radio that has worked fine, so far. However, I wouldn't of made the transition, had these same guys been posting their frequincies out at my flying field!

I understand that the Futaba Fasst system had problems in the beginning. I have not heard a single complaint about the Airtronics system and feel it may be to early to hear anything about Hitec's new 2.4 Ghz system.

So, what's going on here?

RE: 2.4 problems
 

Cambo,

Are you using the same battery for the ignition as the receiver? Some who have done this have reported problems. If so, try a separate battery for the ignition.

Allan

RE: 2.4 problems
 

2 dedicated RX switches, 1 dedicated ignition switch

RE: 2.4 problems
 

So i went out to the field today with my 50cc cap and a replacement aileron servo. I taxied around for about 5 minutes with no lockouts so i went into the air and ended up doing two 10 minute flights. What a difference the new servo made. The aileron trim wasn't constantly changing and the response was just significantly better. No problems encountered in the air. I am convinced that the ar6200 is a poor candidate for gasoline engines with electronic ignitions. The two ar7000's i have are continuing to perform flawlessly so i think i am going to look into purchasing another one.

Cameron

RE: 2.4 problems
 

Update, I was looking at the way i had the plane setup and decided that my ar6200 might not have been at fault. I had the ignition switch and battery about only 5 and 2 inches respectively away from the receiver. So, i moved all the ignition equipment as far to the front of the plane as possible and moved the receiver as far to the back as possible. I have been running the plane for about 35minutes now and have had no receiver lockouts ;). Range checks have demonstrated 100, 80, 60, and 60 ft from different sides of the plane with the engine on. Also, i am testing this through a VERY narrow pathway. Hopefully i will see some improvement with a more open space and with more experimenting.

Cameron

RE: 2.4 problems
 

Final Update:
Plane FLEW today with no problems. The only other mod i made was extending the satellite receiver another 5 inches. I flew 4 flights over 10 minutes each mostly 1/2 to WOT throttle without refueling. 22oz tank and 26cc gasoline is a great match :D

Thanks for all the help everyone
Cameron

RE: 2.4 problems
 

Cambo,

You don't say exactly which servos you were/are using, however, this reminds me of the similar problems that a clubmate of mine was experiencing. He was using a JR DSX9 tx with a AR9000 rx (and also tried many other Speck/JR rx's) the servos were Hitec HS5645 on ailerons in a Yak powered by a MT57. Radio operation was totally unreliable, he just could not fly the model, it was weird! Then he changed the aileron servos to HS5985 and all was well, model flew successfully.
We never found out why this all happened but without expensive test gear to hand you sometimes just have to accept these things.