Turnigy 9X8C V2 Reveiver Interference from ESC

rsabear

Junior Member
I have a 45A Turnigy ESC and today while flying the velco I used to mount the receiver on got unstuck and the receiver moved and ended up onto of my ESC. I lost signal at 350 yards, but managed to do a landing.

Is this a known issue that you must mount of move your ESC and Receiver apart from each other?

Can I also shield the receiver in any way?
 

lobstermash

Propaganda machine
Mentor
That's an issue with any rx, regardless of bandwidth and brand. Shield the receiver by securing your contents better. If velcro doesn't work, compartmentalise your electrics.

The pulse of the ESC creates interference and harmonics in the signals.
 

rsabear

Junior Member
Thank you. That's what I wanted to hear, the RX does not have any shielding. I have now secured the RX better and further away from the ESC. I actually have two RX's in the plane (Bixler), plus a buddy box. There is enough space to move everything well apart.
 

rsabear

Junior Member
I need some more help, please! Did the test flight this morining and nooooooo (it was close twice), I have the same problem. I can narrow it down to CH3 the throttle (from my camera footage). I loose the signal or the ESC cuts out or something. Is there a transmitter tester circuit on the internet, or available for purchase? I have a spare Turnigy 45A ESC and spare Turnigy 2.4GHz 8C receiver. Now need to do some process of elimination or find the fault without flying the plane.
 

lobstermash

Propaganda machine
Mentor
Have you had the receivers for long? If they've been around for a while, check the rx cable where it comes out of the box. Due to the long cable, it often gets folded over itself and the wires fatigue over time and break. I've got two older receivers that this has happened to. I've re-soldered them but haven't used them yet (I'll be doing a range test). That said, new receivers are so cheap...

The ESC is going into failsafe when you lose signal, which by default is to cut the throttle.
 

rsabear

Junior Member
I have not used one of the RX'es yet, other has been in this plane only. I had one crash, but it was not a total and the receiver still looked OK. Loss of signal and ESC - thank you, that rings a bell, I did program the ESC to cut the throttle. I opened the receiver and resoldered the joints but could not see anything suspect. The only kink in the cable is on my RX antenna, but the outer insulation is still fine, no way to check that the antenna is still connected. When I bought the setup I got a spare RX, think it was $9, very cheap. I have put that into the plane to test first. Hopefully it is just the RX and not the expensive ESC. Thanks for your help, good to have a sounding board, I have been flying for less than a year and do not have all the experience yet. I tested the TX on a simulator, it also seems fine with all the pots and switches and CH3/throttle, but that does not test the module.
 

colorex

Rotor Riot!
Mentor
Is the antenna same length as the other receiver you have? Cutting the antenna is the last thing you want to do on a receiver.
 

rsabear

Junior Member
Let me rephrase that one, I removed the heatshrink from the antenna, then 0.3mm of the tip of the antenna and the checked with multimeter, antenna + ground is fine. Then I re-covered the antenna with 4mm heatshrink. The spare RX works in the plane, but I was to scared to fly it out more than 150m and the park I fly is not open and large enough, will drive to bigger open space durning the week and do a range test on the ground first.
 

colorex

Rotor Riot!
Mentor
That might be the issue, cutting the antenna, even if it's just a bit, limits it's range surprisingly much. A friend has had the same problem with his mutilated antenna.
 

lobstermash

Propaganda machine
Mentor
Hmm, yeah, don't mess with your antenna... 2.4Ghz is a pretty short wave, and a few mm off the antenna can make a big difference. In case it ISN'T the antenna (which it probably is):

If you're concerned that your ESC might be the culprit, however, try putting the throttle up to full and keep it there for a bit. The motor is 1900kv, which is fairly fast. Big ESCs (>30A) are generally made for lower kv motors. The ESC might not have the timing quite right and be cutting out. If it's cutting out, try a few different timing settings starting from the lowest and increasing from there.
 

ncbcastro

Junior Member
Hi!!!

I too had the exact same problem with one of these Turnigy 9x8C receivers. It behaved the exact same way you described. I changed out all the electronics, moved the receiver to further away from the ESC, etc, etc... and only to loose control of the plane once again and crash. Then I decided to change the receiver for a Hobbyking 6CH (compatible with the Turnigy) and all my problems disappeared...Never lost control of this plane again!!! The only thing I can come up with is a faulty broken receiver.
 

rsabear

Junior Member
I FINALLY found the problem. Many people on the internet have written off planes because of it. It is a simple problem and if one does not know about it - it will look like signal loss or ESC interference. The problem is actually the power supply to the receiver itself. I have upgraded the LIPO batteries, stock motor, prop and ESC on most of my models, all this in my quest to go higher and faster. The problem with the higher spec motor and prop is the current draw which causes the input voltage to the receiver to drop below a threshold voltage and the receiver reboots as the microprocessor sees the power dip as a brown-out. In the time (few seconds) the receiver takes to reboot, makes it seem if you are experiencing interference or signal loss. This is not unique to Turnigy and affects most receivers. The solution is to install a UBEC to supply power the receiver and servos and remove the positive supply wire from the ESC's build in BEC to power the receiver. Good news is that UBEC's are cheap in the 3-7A range.
:cool:
 

rsabear

Junior Member
HobbyKing: PRODUCT ID: TR-UBEC

TURNIGY 3A UBEC w/ Noise Reduction

Spec. Output: 5v/3A or 6v/3A (Selectable via jumper)
Noise: <50mVp-p(@2A/12v)
Input: 5.5v-23v (2-5S Lipo pack, 5-15cells NiMh)
Size: 41.6x16.6x7.0mm
Weight: 7.5g

Features.
Over current and over heat protection.
Switching frequency 300khz.
Chip Efficiency is 92%. This UBEC utilises switching technology to gain a much higher efficiency than liniar BEC. Which means less heat and longer battery life.
The UBEC is equiped with a noise reduction alloy housing to reduce noise even further.
Incorrect polarity safety feature ensures the UBEC will not be destroyed should the battery be connected incorrectly.
 

colorex

Rotor Riot!
Mentor
Sounds quite reasonable. Note that power irregularity can have a serious impact on any system, like FPV gear, OSD's, etc.
 

colorex

Rotor Riot!
Mentor
UBEC installed = problem gone

I'll put that on my list when I get FPV... but wait... FPV works on 12 volts, is there a way to clean up the 12v line from a battery before it goes to the FPV system? Like, a 12v regulator?
 

Tritium

Amateur Extra Class K5TWM
HobbyKing: PRODUCT ID: TR-UBEC

TURNIGY 3A UBEC w/ Noise Reduction

Spec. Output: 5v/3A or 6v/3A (Selectable via jumper)
Noise: <50mVp-p(@2A/12v)
Input: 5.5v-23v (2-5S Lipo pack, 5-15cells NiMh)
Size: 41.6x16.6x7.0mm
Weight: 7.5g

Features.
Over current and over heat protection.
Switching frequency 300khz.
Chip Efficiency is 92%. This UBEC utilises switching technology to gain a much higher efficiency than liniar BEC. Which means less heat and longer battery life.
The UBEC is equiped with a noise reduction alloy housing to reduce noise even further.
Incorrect polarity safety feature ensures the UBEC will not be destroyed should the battery be connected incorrectly.

That is a great little UBEC. I use it on my Quad to power my ArduPilotMega V2. I have been very impressed with its performance.
It is also worth noting that your ESC will run MUCH cooler without the built in BEC having to supply any circuits.

Thurmond
 

rsabear

Junior Member
but wait... FPV works on 12 volts

such a good question, I never though of it...

Yes, try this one! I also want to test this as I am flying a small 500mA 3S battery for my cameras.

PRODUCT ID: 12V45AUBEC

This Small and lightweight UBEC features a High efficiency switch mode design providing better heat dissipation when compared to linear voltage regulators. The shielded PCB design and output EMF coil makes helps provide a stable and low noise voltage output. This UBEC also features built-in reverse polarity protection.

Specs:
Input: 12V-23V (2-5S Lipoly, 2-6S Li-Fe or 5-15S NiXX Battery Pack)
Output: 12V/3A (Less than 50mV peak to peak voltage @ 2A)
Dimension: 42.4mm x 14.3mm x 20.7mm(LxWxH)
Weight: 13g (wires included)
 

colorex

Rotor Riot!
Mentor
First comment:

This product is not usable for FPV without adding filters. The is either RF noisy, or produces high ripple, either way what was a good picture with another 12v regulator, or lipo, was instantly terrible substituting this regulator.

Looks like it's a no-no.