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Random unpredictable behaviour with receiver/radio

#1
After playing with my servo's for a minute, they all start twitching and have delayed responses as well as just random movements. They are mostly irresponsive. Also if I throttle for a split second, it takes 10 seconds until the prop moves, if it moves at all.

I got it recorded. At 1:00 the servo's get a bit irresponsive and after that it escalates. At the end you'll see the servo's don't do anything at all.
 

FDS

Well-known member
#2
What size is your Bec? If it’s a 1A then it might be browning out. The individual servos are moving fine.
Also NEVER play with motors with props on.
Have you calibrated that ESC? You won’t get any motor movement without doing that. TAKE THE PROP OFF first.
Have you found the source of the issue of the elevator channel?
 
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#3
i had issues similar to yours just recently that i just couldn't figure out
switched out receiver for another and problem solved
im not saying yours will be so simple however if you have a spare receiver try it out :)
 
#4
What size is your Bec? If it’s a 1A then it might be browning out. The individual servos are moving fine.
Also NEVER play with motors with props on.
Have you calibrated that ESC? You won’t get any motor movement without doing that. TAKE THE PROP OFF first.
Have you found the source of the issue of the elevator channel?
I just took off the prop and did another test. After 30 seconds my motor went full throttle autonomonously. I can´t understand why I didn´t realise how much of a blunder that was haha. Thanks for the tip!

The motor works though - until all control goes away, that is.
The individual servos are indeed moving fine. But only until the entire control of the system fades.

My BEC is inside my ESC.

I'm not sure if I fixed the elevator issue properly. The 'fix' for me was to setup a mix with the channel for the stick.
 
#5
i had issues similar to yours just recently that i just couldn't figure out
switched out receiver for another and problem solved
im not saying yours will be so simple however if you have a spare receiver try it out :)
Unfortunately I don't have a spare receiver. And that wouldn't be cheap for me to acquire here.


One thing I noticed is that the ESC vibrates at around 1Hz. (by feeling it with my hand)
[edit] This vibration is the same frequency as the motor making noise, so it's the motor powering that makes the vibration.
 
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rockyboy

Skill Collector
Mentor
#6
I have seen similar issues that end up related to a failing BEC circuit - if you have another ESC, try swapping it in, or use a separate external BEC / 5v receiver power (remember to disconnect the power line between the ESC & receiver when using a different receiver power supply).

If you don't have extra components handy, try unplugging all of the servos and see if the motor and receiver responds normally just by themselves - and then add one servo, and then another. If at some point in this test it goes from working OK to erratically then it's almost certainly the BEC.
 
#7
I have seen similar issues that end up related to a failing BEC circuit - if you have another ESC, try swapping it in, or use a separate external BEC / 5v receiver power (remember to disconnect the power line between the ESC & receiver when using a different receiver power supply).

If you don't have extra components handy, try unplugging all of the servos and see if the motor and receiver responds normally just by themselves - and then add one servo, and then another. If at some point in this test it goes from working OK to erratically then it's almost certainly the BEC.
The issue persists without motor, without servos, and all combinations.

I literally have no spare parts lying around and there is not really a good store where I live so I need to be certain which part is broken before I order any. I am also on a tight budget right now.
 

FDS

Well-known member
#11
The red wire is 5v supply, so you should get near 5v across that and the black or brown which is the ground wire. The third wire is the signal wire, that varies depending on the commands being sent by the receiver.
Which country are you in? There are plenty of sources for receivers that will ship almost anywhere, a second one would help you a lot.
Have you calibrated the Esc? If not do that next. Unplug all the servos, follow this process.
1A55852C-175E-4513-AAD9-DE3E3ED1C6CB.jpeg
Do this first, see if that sorts the motor, then we can work out if you are browning out the BEC.
 

Piotrsko

Well-known member
#12
5 wires to the receiver? Should be 15 per your video. Did you get a dry cell holder for your system to use in a fuel powered vehicle? You could put batteries In That and see if your ESC has gone heat sensitive, or if you have a can of keyboard air, spray that onto the ESC or receiver and see if stuff starts working again. Worse case, an icecube in a baggie against the ESC or receiver. Twitchy means you might have issues with the transmitter sometimes.
 

Merv

Well-known member
#13
If you notice near the end of the video your Rx starts blinking, that a sign that it's not getting a signal. I believe you have damaged the antenna in the Rx. If you take the case off you will find the outer braid of both antenna is damaged where they enter the case. You need to repair or replace the antennas
 
#14
Have you calibrated the Esc?
Yes, I have calibrated the ESC before. I just recalibrated it but I am not sure if I reached the end of calibration before it tripped out again.

If I now plug in the LiPo with only the motor connected and the receiver, the motor starts beeping with random delays.

[Edit] I managed to properly calibrate the ESC but the issue persists
 
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#15
If you notice near the end of the video your Rx starts blinking, that a sign that it's not getting a signal. I believe you have damaged the antenna in the Rx. If you take the case off you will find the outer braid of both antenna is damaged where they enter the case. You need to repair or replace the antennas
I reinspected the circuit. It doesn't seem to be broken to me.
Circuit picture

Also I cannot reproduce the blinking.

I am thinking it might not connect at all anymore. Maybe you're right. Ill upload a video in a minute
 
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Merv

Well-known member
#16
If the other side looks the same, I agree they look fine.
You might play around with the connectors to make sure they are making good contact.

You need to take the prop off before you do any more testing.
 
#19
5 wires to the receiver? Should be 15 per your video. Did you get a dry cell holder for your system to use in a fuel powered vehicle? You could put batteries In That and see if your ESC has gone heat sensitive, or if you have a can of keyboard air, spray that onto the ESC or receiver and see if stuff starts working again. Worse case, an icecube in a baggie against the ESC or receiver. Twitchy means you might have issues with the transmitter sometimes.
3 wires to my receiver. It all used to work before. I'll try the air cooling.

Perhaps because I let it rest, perhaps because of the cooling... it started up with the beeps that its supposed to give. But straight after startup it failed again.
 
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#20
I think this entire issue isn't worth any of our time anymore. I'm just gonna spend the 30 euro for a new ESC and receiver - and wait the long shipping time.

I'd like to thank all of you for the effort!