Garbage sometimes on TelMe telemetry

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ZeXx86
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Ah, can you tell me how long your cable is?

Please note grounding wire should be still present there.

If cable is too long it could cause such issues. We can create new longer cable and test it.
Spirit System developer
buttles
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azaz44, have you done a Mode 1 reset and Mode 4 setup recently? I had similar problems with jLog (after some years) and doing the reset cured it.
azaz44
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buttles wrote:azaz44, have you done a Mode 1 reset and Mode 4 setup recently? I had similar problems with jLog (after some years) and doing the reset cured it.
Sure I did. I installed a brand new Jive Pro 120 in my 570 a month or two ago and went through this setup. And it also happens in my 700 which has Kosmik 200..
azaz44
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ZeXx86 wrote:Ah, can you tell me how long your cable is?

Please note grounding wire should be still present there.

If cable is too long it could cause such issues. We can create new longer cable and test it.
In one heli - Kraken 700 - wire is ~30 cm or shorter. It is a wire from your shop, but I cut it in the middle to extend it. Everything is twisted like the original.

Another heli - Goblin 570 - has it longer, ~40 cm. This is because ESC is at the bottom and it has to be so long. In this case I've bought the right connectors and made wire on my own.

The wire has 2 cables inside, I hope this is correct. I made it exactly as the one I've bought from Spirit shop. I got confused, because on some pictures here http://manual.spirit-system.com/index.p ... _Telemetry there are 3 wires. But cable from the shop has 2.

I check some logs and it turns out, that these params get weird values:
- In Jive ESC temperature, can reach 170 degrees, 200 degress.. In Kosmik I saw a value of 217.
- RPM. In Jive value over 7000 is very common, but I also see 30000, 40000. In Kosmik values of ~6000 are common.
- mAh / consumed capacity. Unfortunately I don't log max value of it so I cannot say, but I'm sure it fails too, because I get premature alarms to land the heli because of too much energy consumed.

I just realized, on the Kosmik the problem is very very occasional, it happens rarely. Maybe once per 50 flights. On Jive it is much more common. Every few flights it happens. And the wire in Jive / 570 heli is longer.
azaz44
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yufasa wrote:I know mine also goes next to motor wires and I have some weird updates sometimes.
Shielding would be worth a try and I was thinking of doing it with a bit of copper braid over the part that runs next to the motor wires. Not sure where to ground it, maybe just to the carbon frame. Will have to check.
Did you try anything? I get annoyed by false alarms in my 570 and I think I need to fix this, but I don't know much about electronics. So the braid needs to be grounded?
ZeXx86
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If the problem will be unresolvable then we could try to implement some data filtering. So that unit will not send invalid data.
Isnt it possible to temporarily shorten the cable? (try another short telemetry cable)
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azaz44
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I think it might be wire length, because in the other heli it is shorter and the problem happens rarely. In both cases telemetry cable is on the same side as motor cables.

In my problematic heli it's going to be easier to add some shielding then to test it with a shorter wire, so I would try this first. I just lack knowledge about electronics to do this properly, maybe I'll try some reading first.
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