RunRyder RC
WATCH
 2 pages [ <<    <    ( 1 )     2     NEXT    >> ] 1534 views Topic Closed
07-29-2012 12:42 AM  8 years ago
Topic Vote0Post 1
Einzelganger

rrKey Veteran

Campbell, Texas

MyPosts All Forum Topic
2.4 ghz question
I'm new to 2.4 ghz. Up 'til my latest radio have always been 72 mhz. I had been hovering, flying small circuits, and had just come back down from about 20' altitude to a smooth tail-in hover at about 50' distance from myself approx 5' over the ground. Bird nosed over into the ground completely on it's own. No wind gusts, no dumb-thumbs, zero twitches or any signs of interference. Both main blades shattered @ mid-blade but in one piece. One main blade ball linkage rod lying on the ground. Head is a FBL conversion for the Raptor 50. All electronics and servos good quality, new, and not on their first flight.
The rest of the story is that I had unthinkingly been aiming the stubby antenna at the bird the whole time. Not in the flipped-up position it should have been.
A week later, I put on new blades, checked every nut, bolt, and widget, and fired it back up (with the antenna flipped up @ 90 degrees to the bird), and everything is perfect.
Did I shoot myself down?
I love the smell of nitro in the morning.
RIP Roman
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 12:52 AM  8 years ago
dkshema

rrMaster

Cedar Rapids, IA

MyPosts All Forum Topic
Need more info. What kind of radio, what receiver, how were the receiver and its antenna oriented? Were the receiver antennas exposed or hidden inside a carbon frame somewhere? What are you using to power the whole works?

Do you have any pictures showing what the setup was, and currently is? This may yield clues.
-----
Dave

* Making the World Better -- One Helicopter at a time! *

Team Heliproz
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 01:06 AM  8 years ago
Einzelganger

rrKey Veteran

Campbell, Texas

MyPosts All Forum Topic
Thanks Dave.
Transmitter = Futaba 7c
receiver = R617fs gy701/governor
receiver is located at front of bird with antennas traveling opposite directions and angled 90 degrees to each other.
Raptor 50V2 plastic frame and canopy
(a lot of wiring in a small clump)
OS 50 non-hyper running smooth @ 1500 rpm head speed
8.5 to 1 gearing.
s9202 servos
Putting some pics in my gallery now.
Pics are there now.
Thanks
I love the smell of nitro in the morning.
RIP Roman
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 02:13 AM  8 years ago
dkshema

rrMaster

Cedar Rapids, IA

MyPosts All Forum Topic
The pictures don't help much, I don't actually see where the ends of your receiver antennas are. It's kind of hard to see anything with regard to the electronics installation.-----
Dave

* Making the World Better -- One Helicopter at a time! *

Team Heliproz
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 02:19 AM  8 years ago
Einzelganger

rrKey Veteran

Campbell, Texas

MyPosts All Forum Topic
My pics are crappy. Sorry. The antennas are in clear tubes angling out the sides then travel down at 45 or so degrees under the electronics tray.

They look like catfish whiskers exiting the upper layer of foam going away from the frame, then travel downwards under the tray.
I love the smell of nitro in the morning.
RIP Roman
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 04:26 AM  8 years ago
Rotormaster

rrVeteran

Australia

MyPosts All Forum Topic
Pointing the antenna directly at the model does not cause trouble with old MHz radios, and I cannot see why it should be the case with 2.4 GHz.

Are any of your wires frayed? I have had this happen before, though you described loosing power suddenly and abruptly with no twitches?
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 04:36 AM  8 years ago
Einzelganger

rrKey Veteran

Campbell, Texas

MyPosts All Forum Topic
I checked my wires and saw nothing frayed. There were no twitches, only the noseover at hover then all stop. Everything seemed fine on radio check at the scene. Receiver voltage at 5.2 under servo load when checked. Battery power from 2 fully charged 4.8v NiMh 2000 mah packs.I love the smell of nitro in the morning.
RIP Roman
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 01:08 PM  8 years ago
Cowjock

rrVeteran

Pa.

MyPosts All Forum Topic
Just had something like this happen a couple of weeks ago with my Trex 700n. Turned out to be the rx lipo, just as I landed the battery voltage dropped and the regulator shut down.Damn that ground is hard! When's the right time to get out of this money sucking hobby?
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 04:04 PM  8 years ago
coptercptn

rrElite Veteran

Mesa AZ. USA

MyPosts All Forum Topic
yes.. it sounds more like a "Brown out" issue than an antennae issue...maybe hook up some telemetry and check it out?Home of the "Sea Cobra".....
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 04:11 PM  8 years ago
dkshema

rrMaster

Cedar Rapids, IA

MyPosts All Forum Topic
Futaba radio kids, no telemetry available. 7C and R617FS combo.-----
Dave

* Making the World Better -- One Helicopter at a time! *

Team Heliproz
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 04:32 PM  8 years ago
unclejane

rrElite Veteran

santa fe, NM, USA

MyPosts All Forum Topic
The rest of the story is that I had unthinkingly been aiming the stubby antenna at the bird the whole time. Not in the flipped-up position it should have been.
It's possible this could have caused an interruption - at 2.4ghz, radio is highly directional and the end of the antenna is definitely a null point in the radiation pattern.

But at only 50' away and a complete loss of signal, that sounds unlikely to me. Probably a hit or two, but not complete loss of control.

Definitely keep the xmitter antenna broadside to the heli at all times, but I think you're right to troubleshoot other possible causes...

LS
SHARE  PM  EMAIL  Attn:RR
07-29-2012 04:45 PM  8 years ago
coptercptn

rrElite Veteran

Mesa AZ. USA

MyPosts All Forum Topic
eagle tree?Home of the "Sea Cobra".....
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 05:47 PM  8 years ago
Cowjock

rrVeteran

Pa.

MyPosts All Forum Topic
Head is a FBL conversion for the Raptor 50
What FBL unit are you using? Strange things happen went these units come loose from their mounting tape. Could the unit be loose or coming loose from the mounting tape? Just a thought.
Damn that ground is hard! When's the right time to get out of this money sucking hobby?
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 06:01 PM  8 years ago
Einzelganger

rrKey Veteran

Campbell, Texas

MyPosts All Forum Topic
GY701 NOBAR. Snug in its mount.
70% on dual rates.
Smooth as silk through 8 tanks on PCM 72MHZ.
Switched over to 2.4 ghz and this happened on the 2nd tank.
Luck on the first?
I love the smell of nitro in the morning.
RIP Roman
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 06:08 PM  8 years ago
unclejane

rrElite Veteran

santa fe, NM, USA

MyPosts All Forum Topic
One thing to check is to see what it does when you turn the xmitter off. I.e. power up the flight system on the bench and shut off the xmitter. See what happens..

I don't know if the 7C and that RX have a particular failsafe setup, but on the 8FG/R6208 I use, the failsafe by default is to keep everything where it was when reception was lost.

It probably shouldn't just go bonkers .

But that'd be one troubleshooting step to see what happened. I'd tend to think if it did something suddenly there was another problem apart from signal loss...

LS
SHARE  PM  EMAIL  Attn:RR
07-29-2012 06:12 PM  8 years ago
TMoore

rrMaster

Cookeville, TN

MyPosts All Forum Topic
The TX antenna should be pointed straight up or straight down on Fasst and Airtronics. This helps with maintaining good dispersion of the signal.

The RX antennas are coax so the last 25mm of the antenna are what should be positioned correctly. They ends should be at 90 degrees to one another and it really doesn't matter what plane the antennas are in as long as that 90 degree is maintained. 90 degrees is an ideal, in reality you just need to be close. The ends should also be in the clear, not up against CF because that will block the reception as well.

Here is a Raptor 50 that works quite well.

Do the range check in low power mode and you should have at least 90 feet of ground range in low power mode. If you have this, you should be OK barring any other calamity that might occur.

Part 107.
The only ZERO flight hour certificate in the world.
It's like getting a driver's license without the driver's test.
SHARE  PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR
07-29-2012 06:40 PM  8 years ago
Einzelganger

rrKey Veteran

Campbell, Texas

MyPosts All Forum Topic
I've got more than one problem.

unclejane: my fail-safe cuts to about 10% throttle with zero other changes. I cycled power @ tx several times. It will increase to 10% if closed or cut to 10% if above that.

TMoore: I've got my antenna set up exactly backwards. I have them exiting the receiver at and maintaining 90 degree separation until they clear the tray and come together and meet underneath at 90 degrees. Also, they are enclosed in tubes at their ends, not their beginning.
I will fix that now.
How do I attach a pic from my gallery to this post?
I love the smell of nitro in the morning.
RIP Roman
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 07:21 PM  8 years ago
TMoore

rrMaster

Cookeville, TN

MyPosts All Forum Topic
You can use tubes if you want but soft velcro is the best. All you care about is the final 25mm, the rest is along for the ride.

Click on the bottom of the pic in your gallery, this copies the pic to the clip board, then paste into your post.

TM
Part 107.
The only ZERO flight hour certificate in the world.
It's like getting a driver's license without the driver's test.
SHARE  PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR
07-29-2012 07:49 PM  8 years ago
Einzelganger

rrKey Veteran

Campbell, Texas

MyPosts All Forum Topic
This is my antenna setup before and after.
I get 50 feet on low power range test. Its sketchy to 60 feet and gone after that.

I love the smell of nitro in the morning.
RIP Roman
SHARE  PM  EMAIL  GALLERY  Attn:RR
07-29-2012 07:53 PM  8 years ago
TMoore

rrMaster

Cookeville, TN

MyPosts All Forum Topic
60 feet is OK, turn the heli 90 degrees and try it. I will usually test the range in 3 orientations just to be sure if the antenna's aren't totally in the open. Make sure the TX antenna is pointed in the right direction.

TM
Part 107.
The only ZERO flight hour certificate in the world.
It's like getting a driver's license without the driver's test.
SHARE  PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR
WATCH
 2 pages [ <<    <    ( 1 )     2     NEXT    >> ] 1534 views Topic Closed
Print TOPIC

 6  Topic Subscribe

Wednesday, April 14 - 9:44 am - Copyright © 2000-2021 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online