RC Jets Discuss RC jets in this forum plus rc turbines and ducted fan power systems

Poor Transmitter Antenna Positioning may Cause Lockouts

Reply
Old 04-21-2014, 07:31 AM
  #126
luckyflyer
 
Join Date: Feb 2007
Location: Carlsbad, NM
Posts: 176
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I think we all know what's really going on here. ...............N*S*A

Last edited by luckyflyer; 04-21-2014 at 07:34 AM.
luckyflyer is offline  
Reply With Quote
Old 04-21-2014, 07:43 AM
  #127
mattnew
 
Join Date: Jan 2013
Location: Haverhill, MA
Posts: 810
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Lets see... Its April...

For many/most of us March/April is likely the beginning of the flying season...

People pull their planes out of the basement... garages... Arizona is drier than where I fly, but one thing I have to pay attention to is corrosion that may have occurred over the months where my planes may have had to be stored in less than ideal conditions.

My thought is in the north-east its not necessarily uncommon for a perfectly fine setup that was put away in november to need some new switches, or a new battery or wires in march when its pulled out to fly it again... so we tend to automatically check that sort of thing.... I'm wondering if in Arizona that is less common due to the different climate... but you may still run into those issues, although less frequently....to the point where it doesn't get checked regularly.


just a thought...
mattnew is offline  
Reply With Quote
Old 04-21-2014, 07:57 AM
  #128
dbsonic
 
dbsonic's Avatar
 
Join Date: Oct 2005
Location: san jose, CA
Posts: 781
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

So, how many have had the rare occasion of "RC-off" read on the ECU after a flameout(and you did not command shutdown) on an otherwise very reliable aircraft and engine? Let's define rare in this case to be about 1 in 100 flights.

Presumably you've done the proper rx antenna install. Could this be due to tx orientation goof up or something else?
dbsonic is offline  
Reply With Quote
Old 04-21-2014, 08:27 AM
  #129
DISCUS54
 
Join Date: Mar 2008
Location: Sun City, AZ
Posts: 283
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Quote:
Originally Posted by blhollo2 View Post
No, nothing is going on with futaba, keep calm and carry on.
Andy, you should know by now that without supported facts your going to get beat up....heck, with supported facts the sheeple will continue to beat on you, and the world is lousy with them. I can see where some of these lockouts might have been sponsored pilots but not all, right? It would be beneficial to hear what "exactly" happened there.
DISCUS54 is offline  
Reply With Quote
Old 04-21-2014, 08:52 AM
  #130
AndyAndrews
Thread Starter
 
AndyAndrews's Avatar
 
Join Date: Feb 2007
Location: Little Rock, AR
Posts: 5,995
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Quote:
Originally Posted by DISCUS54 View Post
Andy, you should know by now that without supported facts your going to get beat up....heck, with supported facts the sheeple will continue to beat on you, and the world is lousy with them. I can see where some of these lockouts might have been sponsored pilots but not all, right? It would be beneficial to hear what "exactly" happened there.
I've asked the moderators to delete this entire thread. I was wrong to post it like I did. There are just too many variations that could cause these things it is shouldn't have been my place to assume or even call out others. I apologize to the ones I named. I shouldn't have put them in this situation and I feel bad about it. For those who said from the beginning that this thread would serve no good, I agree with you. It hasn't.

Regards,
Andy

Last edited by AndyAndrews; 04-21-2014 at 08:47 PM.
AndyAndrews is offline  
Reply With Quote
Old 04-21-2014, 09:53 AM
  #131
stevekott
 
stevekott's Avatar
 
Join Date: Nov 2006
Location: yorba linda, CA
Posts: 588
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Quote:
Originally Posted by dbsonic View Post
So, how many have had the rare occasion of "RC-off" read on the ECU after a flameout(and you did not command shutdown) on an otherwise very reliable aircraft and engine? Let's define rare in this case to be about 1 in 100 flights.
If it reads RC-Off your Fail safe is NOT set up properly. It should read "Failsafe". The Rx needs to send a Failsafe command to the ECU that is below that of "Throttle Down, Trim Down". If regular RC Off is say -100 Failsafe needs to be -110. Something below normal range.

The Problem: If you get a quick failsafe glitch set up to failsafe at -100 that the turbine will shut down instantly. What it's designed to do is shutdown after 2 seconds of Failsafe (below -100). A quick glitch would hardly be noticed but a turbine out trying to glide back to the runway causes a whole new set of problems.
stevekott is offline  
Reply With Quote
Old 04-21-2014, 09:54 AM
  #132
speedracerntrixie
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 5,340
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Andy, I think there is some good info here in general. So far I think things have been pretty quiet considering.
speedracerntrixie is offline  
Reply With Quote
Old 04-21-2014, 10:21 AM
  #133
dbsonic
 
dbsonic's Avatar
 
Join Date: Oct 2005
Location: san jose, CA
Posts: 781
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

So Steve, if I read you correctly, by using the radio systems failsafe to command a shutdown, it is much more harsh than using the ECU based failsafe which allows for a bit of margin in terms of time. Point well taken. I've tested it and the shutdown is immediate in my case.

But, unfortunately it still means the rf link was compromised in my case unless something else can create an "Rc-off" condition( assuming I didn't accidentally with my hand, and I verified the trim in this case to still be full up)
dbsonic is offline  
Reply With Quote
Old 04-21-2014, 10:24 AM
  #134
RCKen
RCU Forum Manager/Admin
 
RCKen's Avatar
 
Join Date: Jul 2002
Location: Lawton, OK
Posts: 26,763
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Quote:
Originally Posted by AndyAndrews View Post
I've asked the moderators to delete this entire thread. I was wrong to post it like I did. There are just too many variations that could cause these things it is shouldn't have been my place to assume or even call out others. I apologize to the ones I named. I shouldn't have put them in this situation and I feel bad about it. For those who said from the beginning that this thread would serve no good, I agree with you. It hasn't.

Moderators, please delete.

Regards,
Andy
Andy (and others),
Unfortunately we are in a bit of a sticky situation here where we can't simply delete a thread because it didn't go the direction it was intended. Believe me I understand and feel your pain here, but myself and my moderators have to moderate RCU by our Community Rule and we can't take actions unless there is a rule being broken here. If there some rule being broken that I've missed please point it out to me. But even if there is a broken rule it's unlikely that we would delete the thread, but rather we would simply lock the thread and let is slide down the forum listing, unless once again there is something here that I am missing.

Ken
RCKen is offline  
Reply With Quote
Old 04-21-2014, 10:35 AM
  #135
ToxicSludge
 
ToxicSludge's Avatar
 
Join Date: Nov 2013
Location: SW Oregon
Posts: 27
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I gather that all these 'glitches' happened in southern AZ.You have Fort Huacuca that,the last that I knew,does a lot of radio work and various testing of new commo systems etc.They don't have to cause interference directly on the 2.4 ghz band,but it could be caused by harmonics off of another band in use.Also maybe some ducting was happening to,that may have been the cause of this.As far as antenna orientation goes,keep it as vertical as possible,at all times.The circuitry inside the radio is designed for a vertical antenna.The more 'off vertical' the antenna is,the transmitter might be folding back the power output due to a much higher swr.This protects the power amp in the transmitter,or should.To really get an idea of this,you would need a field strength meter that is capable of going up to 2.4 ghz.band.That will show you any lobes and give you a better understanding of how an antenna works for our rc stuff.
ToxicSludge is offline  
Reply With Quote
Old 04-21-2014, 10:52 AM
  #136
stevekott
 
stevekott's Avatar
 
Join Date: Nov 2006
Location: yorba linda, CA
Posts: 588
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Quote:
Originally Posted by dbsonic View Post
So Steve, if I read you correctly, by using the radio systems failsafe to command a shutdown, it is much more harsh than using the ECU based failsafe which allows for a bit of margin in terms of time. Point well taken. I've tested it and the shutdown is immediate in my case.

But, unfortunately it still means the rf link was compromised in my case unless something else can create an "Rc-off" condition( assuming I didn't accidentally with my hand, and I verified the trim in this case to still be full up)
Exactly Right !

I'm keen to this as a few months ago I was spotting for a good friend with a beautiful F-4 twin. He got pretty far out Tx antenna was horizontal had a split second glitch, barely noticeable except ... both turbines shut down. Our field is on a hilltop, not very forgiving and he sadly lost the whole thing as he couldn't make the runway with no power. Had he had that two seconds of wait time prior to shutdown he would have continued the flight without incident. ECU's recorded "RC-Off". Also his Rx antennas were low in the air frame just in front of the turbine, batteries and ball of wires. Plane flying away to the left, antenna pointed to the right (bottom of antenna pointed at plane) Perfect storm of bad orientation.

I went home, checked my planes and found two of them had the Tx Failsafe set up the same way.

I just had to temporarily change the servo endpoint from -100 to -120, reset the new Failsafe point on the TX and then set the servo endpoint back to -100.

You can test it using the HDU (engine off) and turn off the Tx. The HDU gets a little F/S on the screen once the Tx goes off and it goes away after the Tx is turned back on.

Last edited by stevekott; 04-21-2014 at 11:02 AM.
stevekott is offline  
Reply With Quote
Old 04-21-2014, 11:33 AM
  #137
smaze17
 
Join Date: Dec 2001
Location: Cornelius, NC
Posts: 1,416
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Jeez - if someone posts a question about a radio manufacturer it's like some people think it's an attack on them. Then people try to make it out to be a Jr vs Futaba thread. IMO Andy is asking an honest question and for that he gets called a troll.
smaze17 is offline  
Reply With Quote
Old 04-21-2014, 11:33 AM
  #138
F-16 viperman
 
Join Date: Apr 2006
Location: , CA
Posts: 127
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Smile

Quote:
Originally Posted by AndyAndrews View Post
I've asked the moderators to delete this entire thread. I was wrong to post it like I did. There are just too many variations that could cause these things it is shouldn't have been my place to assume or even call out others. I apologize to the ones I named. I shouldn't have put them in this situation and I feel bad about it. For those who said from the beginning that this thread would serve no good, I agree with you. It hasn't.

Moderators, please delete.

Regards,
Andy
andy, don't regret your thread. if it makes just one person more vigilant, and check out somthing pre-flight that they normally would'nt have checked, and prevents somthing bad, its worth it. Thank You. as for antenna position people are talking about, I flew orbit, Proline, c&s F&M, Bonner, heathkit, Royal, Micro avionics, Controlaire, Kraft, Citizen-ship, Jr, Spektrum, Futaba, and probably some others i can't think of right now, and with all of them, You don;t point the antenna at the model. This happens to be easier with the new adjustable 2.4 antennas which I advise friends to always point at their head while flying. If They lose the signal then because of the antenna pointing straight at the aircraft, immediately put the TX on the ground and pull out the umbrella the way the coyote does just before the rock lands on Him. LOL

Last edited by F-16 viperman; 04-21-2014 at 12:18 PM.
F-16 viperman is offline  
Reply With Quote
Old 04-21-2014, 11:43 AM
  #139
F-16 viperman
 
Join Date: Apr 2006
Location: , CA
Posts: 127
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Seriously, The fact that andy's post will make more people mindful of Their antenna position makes this thread worth it!

Last edited by F-16 viperman; 04-21-2014 at 12:19 PM.
F-16 viperman is offline  
Reply With Quote
Old 04-21-2014, 11:54 AM
  #140
Jim Branaum
 
Join Date: Oct 2002
Location: Fair Oaks Ranch, TX
Posts: 2,603
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Quote:
Originally Posted by SkidMan View Post
Jim Branaum - Pointing one end of the antenna toward the ground not any different than pointing it towards the sky. The power radiated off of each end of the antenna is essentially the same (the far end, or the end fastened at your transmitter). The real radiated power is perpendicular to the antenna axis, not the end of the antenna.
Within some parameters, you are correct if our radios do not use the ground plane as others have suggested. I am not really sure that the transmitter can tell if it is vertical, horizontal, or whatever by the SWR nor am I sure the final stage amplifier is anything other than fixed (can't adjust power up or down). However, I don't know it all nor am I even sure I want to! .

However, the real 'trick' is to get the real power radiated to the area the aircraft is flying in and I don't think that is always true when your antenna is pointed at the ground but I am also not sure it is true if the antenna is pointed up at any angle other than 90 degrees.

Andy, regardless of the naysayers there are some things that folks should look at in their radio systems and IMNSHO this thread is bringing some of those to light.

YMMV
Jim Branaum is offline  
Reply With Quote
Old 04-21-2014, 12:12 PM
  #141
pflynn73
 
Join Date: Mar 2008
Location: Boulder City, NV
Posts: 66
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Some of you act like you sleep with your Futaba. Give me a break. This guy is trying to help us. Like I said before anybody who rips Andy is a true DB.
pflynn73 is offline  
Reply With Quote
Old 04-21-2014, 12:21 PM
  #142
GrayUK
 
GrayUK's Avatar
 
Join Date: Oct 2003
Location: Dunstable, UNITED KINGDOM
Posts: 3,598
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

FASST since day 1.
Apart from the early G.U.ID issue..I have never had or seen a problem with it.
I would not fly anything else.
GrayUK is offline  
Reply With Quote
Old 04-21-2014, 12:53 PM
  #143
SushiHunter
 
SushiHunter's Avatar
 
Join Date: Dec 2013
Posts: 540
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I use a 18mz and there have only been one occasion that I've experienced this issue. I'm thinking it could have been rx related or factors outside of the system such as interference from something else or, related to the environment (terrain). The plane that I was flying at the time this happened, has the simple and basic 6 channel rx in it. All my other planes have the R7008SB rx and thus far have all been completely flawless. So the only difference in system between all the planes I've flown with my 18mz and the one that did have this issue but only once so far, is the rx and the environment. I was also somewhat near the Stanford "dish" when the issue occurred, so this is also why I think there is a possibility the issue was caused by interference outside of my rc system. It's only occurred once and I've been using my 18mz for a little over a year now, and the one time it did happen, only did so for just a few seconds, which didn't result in crash or loss of ac since I had plenty of alt at the time.

Last edited by SushiHunter; 04-21-2014 at 01:25 PM.
SushiHunter is offline  
Reply With Quote
Old 04-21-2014, 03:06 PM
  #144
sirrom
 
Join Date: Dec 2001
Location: Sarasota, FL
Posts: 848
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Quote:
Originally Posted by dubd View Post
I fly with a Futaba 18mz and welcome Andy's inquiry. If there are crashes from lock-out then we should talk about it and try to understand if it's a real problem or localized. That is what forums are for! The guys who are claiming this is a brand war are going to turn it into that.
I completely agree with you but don't start the thread with, "I heard of this, but can't tell you who told me....". Come in and state the facts, state what happened, to who it happened, the circumstances, the setup, etc. He took the wrong route to start a legitimate conversation about a possible problem.

Patrick
sirrom is offline  
Reply With Quote
Old 04-21-2014, 04:57 PM
  #145
blhollo2
 
Join Date: Oct 2008
Location: fuquay varina, NC
Posts: 818
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Quote:
Originally Posted by pflynn73 View Post
Some of you act like you sleep with your Futaba. Give me a break. This guy is trying to help us. Like I said before anybody who rips Andy is a true DB.

WAIT a minute....you DONT sleep with your futaba radio?!.... No one should rip Andy over this posting as it is a very useful info and pretty good topic,very informative.

Now... With that said..No, nothing is going on with futaba, keep calm and carry on.
blhollo2 is offline  
Reply With Quote
Old 04-21-2014, 05:28 PM
  #146
raubold
 
Join Date: Nov 2004
Location: Tehachapi, CA
Posts: 301
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Quote:
Originally Posted by oneaew@msn.com View Post
what is a power box?
i like this one, really do hehe
raubold is offline  
Reply With Quote
Old 04-21-2014, 05:40 PM
  #147
bjr_93tz
 
Join Date: Dec 2006
Location: ToowoombaQLD, AUSTRALIA
Posts: 872
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Quote:
Originally Posted by oneaew@msn.com View Post
what is a power box?
Quote:
Originally Posted by raubold View Post
i like this one, really do hehe
Someone might be coming here because this thread's on the most active list, and not because they fly jets (or IMAC planes)? I know I did, and I don't.
bjr_93tz is offline  
Reply With Quote
Old 04-21-2014, 06:54 PM
  #148
mongo
 
mongo's Avatar
 
Join Date: Dec 2001
Location: Midland, TX
Posts: 2,287
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

ken,
shouldn't this one actually be in the radio section, annyway?
mongo is offline  
Reply With Quote
Old 04-21-2014, 08:14 PM
  #149
ira d
 
Join Date: May 2003
Location: Moreno Valley, CA
Posts: 3,030
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Quote:
Originally Posted by sirrom View Post
I completely agree with you but don't start the thread with, "I heard of this, but can't tell you who told me....". Come in and state the facts, state what happened, to who it happened, the circumstances, the setup, etc. He took the wrong route to start a legitimate conversation about a possible problem.

Patrick
Well said.
ira d is offline  
Reply With Quote
Old 04-21-2014, 08:35 PM
  #150
AndyAndrews
Thread Starter
 
AndyAndrews's Avatar
 
Join Date: Feb 2007
Location: Little Rock, AR
Posts: 5,995
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Quote:
Originally Posted by ira d View Post
Well said.
I agree.. but the cat is out of the bag and I can't put it back. Again, I apologize profusely for bringing this up the way I did. I tried to get Ken to nix the whole thing but he can't due to RCU rules etc.

Sorry guys.
AndyAndrews is offline  
Reply With Quote
Reply


Thread Tools
Search this Thread
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 01:11 AM.