RunRyder RC
WATCH
 1 page 1337 views POST REPLY
HomeAircraftHelicopterRadio - Spektrum DSM › 2.4G interference(?) issue
01-17-2010 08:30 AM  8 years agoPost 1
RLHeli

rrApprentice

Auckland - New Zealand

My Posts: All  Forum  Topic

Greetings group,

I have been hit by RX went into hold back 2 weeks ago. Damaged blades and boom. Could not reproduced the hold at all and was very troubled by it. Fortunately, I bumped into a fellow Specktrum user who kindly lend me his log unit and I was horrified from the numbers logged.
With engine in idle, I held the bind button on TX to reduce signal strength and walked around my model in a radius of ~2m for around 5mins. I carried out this test 3 times and in the worst run I got 216 fades on B receiver and around 190 fades on R receiver and 5 frame loses. In the other runs, receiver B & R registered largest numbers of fades in the region of 170+ but there were no frame lost in those two runs. I then carry out 2 tests without engine running and in both runs, I had very small number(< 5) of fades on receiver B & R, no fades on the rest and certainly no frame lost.
My question is... Is my test a proper test? If yes, what do you think about the numbers when engine is running and why receiver B & R always register highest number of fades? My TX is 12X and RX is RD1221. I have no clue what next. Your ideas are much welcomed.

PM  EMAIL  GALLERY  Attn:RR  Quote
01-17-2010 08:56 AM  8 years agoPost 2
decoy26

rrNovice

Omaha Nebraska

My Posts: All  Forum  Topic

How is your voltage and did you double check all connections to the receiver. Any wires pulling out of the satellites? Also you may try repositioning your satellites?? My thoughts, I ran into the same thing but on my IMAC plane. Not sure I helped but wanted to throw that out there.

PM  EMAIL  GALLERY  Attn:RR  Quote
01-18-2010 07:03 AM  8 years agoPost 3
RLHeli

rrApprentice

Auckland - New Zealand

My Posts: All  Forum  Topic

Thanks decoy26, I think RX voltage shall be at 5.0V as I run PerfectRegulator. Engine at idle runs were taken first before the engine at rest control runs. I think I am going back to 4.8v Ni-Mh to take regulated power out of the puzzle and swap the sat. RX to different ports to see if the fades follows sat. RX. I hope this is the case. You mentioned you relocate sat. RX, would you mind sharing where they were and where you relocate them to? Cheers.

PM  EMAIL  GALLERY  Attn:RR  Quote
01-22-2010 03:42 PM  8 years agoPost 4
CoronaL

rrKey Veteran

Winnebago IL

My Posts: All  Forum  Topic

couple things I would try

#1---with the data logger, read the rx voltage. it will display that as the first option w/out hitting the data logger button. Move servos etc... and make sure voltage says put and doesn't sag <4.8v.
Ruling or trying to rule out power problem. Another issue, is if you have a bad servo. You can stall that servo and create ALOT of drain on the system. I would think it would manifest it'self diffently as a back end problem, and not create fade/loss, but I could be wrong there too.

#2--If you can borrow a friends TX, try to bind your plane to his TX. SEtup a basic model, don't spend all day lol. Just want to do a range check with this, and see wtih the data logger if you are still getting the same # of fades/etc... If you are, it could be an Rx problem, assuming the Rx is setup properly and orientated correctly.
Rule out Rx as issue. If loss/fade repeated, it's the rx, or the placement/setup.

#3--If you have a spare Rx, or heli with a different Rx. log that and see if you are getting any loss/fades. Ruling out TX as issue. If you are getting loss/fades it's likely you have a low output or Tx problem.

If the Rx/TX checks out ok, independently. Then you may want to remove servos and or other electronics one by one, to see if you find a culprit.

Randy!!! I am the liquor

PM  EMAIL  GALLERY  Attn:RR  Quote
01-24-2010 10:47 PM  8 years agoPost 5
RLHeli

rrApprentice

Auckland - New Zealand

My Posts: All  Forum  Topic

Thanks guys. Your responses are much appreciated. Troubleshooting this kind of issue is a rather lonesome experience and your posts really helped keeping me going. I found the flight logger a very helpfull tool for issue like this.
Did get some nervous hovering late SUN afternoon without any nasty surprises but I am still no where near pin point the exact cause of previous crash and abnormal fligh logger readings.
I went to the field late SAT afternoon with flight logger plugged in my well behaving 600NP, thinking I would use those read-outs as control. Not surprisingly after 8 mins of "give it all, near and far", fades on RX bearly made 2 figures with most less than 5. Repeated twice, not as violent, similar results.
Then I plugged flight logger into my Vibe 90 SG and carried out the same engine at idle walk test and this time, there was no fades at all! The only change I've made was to unbundle RX cable from servor cables and leave them hanging. I then went back to the locations where I crashed and where I had the tests a week ago and still 0 fades. Same story on Sunday. Did eventually took it into circuits but was nervous as...
I don't think servo signal will affect RX signal that much as in my 600NP, RX cables are bundled with servo cables too. I am leaning towards a interference source at field but what could it be?

Regards,

PM  EMAIL  GALLERY  Attn:RR  Quote
01-24-2010 10:59 PM  8 years agoPost 6
CoronaL

rrKey Veteran

Winnebago IL

My Posts: All  Forum  Topic

so you are getting "more than 2 figures" of fade? I take that to mean 10+?

When I look at mine, and I have a logger attached to several helis, I generally only get 2-3 fade/loss and no drops.

I had a "back end" issue that I was lucky enough to be experiencing at a local fun fly and John Adams from JR was there and helped explain some things to me. A back end issue he said was something that was causing glitches that was "post" reciever. IE servo, sensor etc... I ended up re-routing some wires, putting a diff rx battery in, and a new gov sensor and the glitches went away. I was getting no loss/fade/drops etc... and the Heli was glitching big time.

Obviously your issue seems to be related to loss etc... But something to think about anyway.
thx

Randy!!! I am the liquor

PM  EMAIL  GALLERY  Attn:RR  Quote
01-25-2010 05:22 AM  8 years agoPost 7
RLHeli

rrApprentice

Auckland - New Zealand

My Posts: All  Forum  Topic

Hi CoronaL, thanks for putting in your thoughts. Yes, I remembered seeing 12 fades on the RX that is on the left hand side frame next to MP5 front section. I expect it to have some fades as it's location really is not ideal

I think what I am going to do next is to bundle the RX cables back in with servo cables and see what comes out of this. Humm... counting down to SAT. Haha...

PM  EMAIL  GALLERY  Attn:RR  Quote
01-26-2010 10:11 PM  8 years agoPost 8
uk-heliman

rrNovice

Oxfordshire- UK

My Posts: All  Forum  Topic

As others have suggested I am interested in how you came to the conclusion the RX went into hold as the RX you are using has high multipath diversity? Do you believe you had a situation where the RX (and it's SAT's) could not see a signal?

I believe you are right to look at your RX positioning, they should be positioned so as to always have line of sight (or as best you can) with the TX in any orientation of the helicopter. I always keep servo wires together and RX wires together, but both seperate from each other.

In my opinion, other components are probably more likely to have caused the problem:

1) Voltage Regulator
2) Stalled Servo / Bad Servo
3) Bad TX or RX

Unfortunatly the only way to find out is trial and error or fit an Eagletree with Spektrum cable you can then monitor Main voltage, RX performance and individual servo current and play it back after the flight.

Robbe Nova, Quatro & Spirit LE, TREX 450SE, Century Swift 550 Carbon, Vario EC135

PM  EMAIL  Attn:RR  Quote
02-01-2010 09:19 AM  8 years agoPost 9
RLHeli

rrApprentice

Auckland - New Zealand

My Posts: All  Forum  Topic

Arggh...
This issue is no fun at all but I have nailed it. It was RX related. It is very difficult to reproduce this issue, indeed, impossible. It just comes and goes... Fortunately, this time it stuck around long enough for me and my mate to do some sat rx port swapping to find out that it is always those two ports that have outrageous fades. So RD1221 into the parts bin... A new RD921 is in the machines now and have done 2 tanks of hovering with no fades at all using two out the 3 sat receivers.
Thanks guys for your ideas and support. This will take a lot longer with me working on this along. Deeply appreciated!

PM  EMAIL  GALLERY  Attn:RR  Quote
02-01-2010 11:17 AM  8 years agoPost 10
1275mini

rrKey Veteran

Wirral North West U.K.

My Posts: All  Forum  Topic

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
02-01-2010 10:56 PM  8 years agoPost 11
KingJoeMack

rrVeteran

New Baltimore, Mi USA

My Posts: All  Forum  Topic

I go to a indoor soccer arena and fly thruout the winter. Aprox 60-80 pilots. Last 2 weeks MAJOR problems. 5-10 hits per flight, some with very bad outcomes. Some of the sponsers have worked with Spectrum over the years putting on informative seminars.
Spectrums unoffical response:
Yes we know there are issues.
Recomend recivers with a satilite antena (AR7000, AR6200...)
as well as on the reciver and satelites, bending the small antena 90 degree halfway out. On your transmitter, keep the antens bent and not straight out.
This has seemed to have helped, but no one knows for sure.
There may be one bad transmitter in the bunch doing this, as last year there were no issues.
Spectrum say this could not be caused by a single bad transmitter by the nature of the design.
Take it for what it is worth.
Good Luck

Fly with scheduled ground contact !

PM  EMAIL  GALLERY  Attn:RR  Quote
02-02-2010 01:56 PM  8 years agoPost 12
1275mini

rrKey Veteran

Wirral North West U.K.

My Posts: All  Forum  Topic

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
WATCH
 1 page 1337 views POST REPLY
HomeAircraftHelicopterRadio - Spektrum DSM › 2.4G interference(?) issue
 Print TOPIC  Make Suggestion 

 2  Topic Subscribe

Friday, July 20 - 10:11 am - Copyright © 2000-2018 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online