Strange glitchiness with sidewinder and MM with ccbec

[BrianG]

Wire proximity is just one possible cause. Noisy BECs can certainly be an issue as well.

[MTBikerTim]

Try changing the batteries in your TX. My mini-t glitches when my tx battery starts to get low. The TX battery isn't even that low when the glitching starts (10.7v or something close to that) but when I charge the pack the glitching goes away.

[Sammus]

Yeah I though of that... the battery is at 12V so no problem there. Plus its the same Tx I use for all 5 of my cars and only the rustler, when running a ccbec, exhibited the same behaviour.

Where can one buy a koolflight bec? According to their website, they dont take online orders anymore, and none of their resellers stock the car version. I think I remember seeing it in the rcm store but am having trouble finding it again.

Then again there is always the option of just not using it... I run 4sA123 in my rustler through a sidewinder with no BEC now and havent had issues...

[BrianG]

If you can't get a KoolFlight BEC, try a WesternRobotics BEC, or a DimensionEngineering Sport BEC.

[Sammus]

Cheers. I like that dimension one how it plugs between the ESC and Rx, if theres only one lead to the esc, and that one lead is toted as noise free, perhaps there's less chance of glitching than trying to suppress to two seperate signal wires.

Before I spend $100 replacing my BECs (got the crt.5, my buggy build, and re-bec'ing my rustler) I think I'll try some of those ferrite rings, I've heard good things about them.

[Sammus]

I think I figured it out (kind of) - I added one of these across Ch3 on my Rx, and one of these close to the plug on each of the BEC ouput and ESC output leads (ie close to the Rx). It actually made the glitching a lot lot worse. (edit: I just remembered last night when I reprogrammed the ESC I hadn't tried it since, so it also could've been any of the reprogramming I did: Punch control from 20% to 0%, start power from High to Low.) I unplugged the cap and it was the same - heaps worse than ever before.

On a slightly lighter note, it was glitching so bad I could see what was happening. The Rx is resetting.

Every now and then (almost guaranteed to happen if I hold reverse for a second then for full forward throttle - with no wheels on the car, just sitting there). You can see the 3PM Rx light go off. Sometimes it goes off for a second, sometimes it just goes red (in which case I think its still resetting, but for such a small fraction of a second I cant actually see the power cut). But every time it takes a second for the Rx/Tx to recognize each other.

I hooked a DMM across my battery leads and verified that the voltage was dropping quite low. Now I can't be sure exactly how much because my MM only updates ever 0.5s or so, but most of the time, full reverse to full thottle, the voltage (4s A123) drops from ~13 to just above 12V (what I could see). When the reset glitch happened, I managed to see 8V on the DMM - and presumably it dropped quite a bit lower than that for the Rx to switch off.

I still don't understand though. It seems to happen only with the BEC connected. Ferrite EMI suppressors made the problem worse. 1000uf 10V cap in the Rx didn't make any noticable difference.

Any suggestions except (a) run with no BEC. or (b) get one of the o ther BECs mentioned above.

I think my findings imply its not a noise issue, but I still can't figure out why it is happening. I know A123 cells are prone to voltage drop, but geez it's barely pulling any current, I can't help but thing something else is going on.

A lot of signs point to the batteries and/or the ccBEC. But at the same time, My Revo conversion runs flawlessly with the same BEC and 7s A123, is twice as heavy and geared to go faster. So that could suggest the ESC. Hmm...

[Sammus]

Alright, I removed the ferrite rings and I'm back to square one. The super glitch action disappeared, still does it a little bit like before though. Cap doesn't make any noticeable difference.

[MTBikerTim]

You don't have an eagle tree or other logger do you? It would be interesting to see what current you are pulling when the voltage drops.

Originally Posted by Sammus

Yeah I though of that... the battery is at 12V so no problem there. Plus its the same Tx I use for all 5 of my cars and only the rustler, when running a ccbec, exhibited the same behaviour.

Where can one buy a koolflight bec? According to their website, they dont take online orders anymore, and none of their resellers stock the car version. I think I remember seeing it in the rcm store but am having trouble finding it again.

Then again there is always the option of just not using it... I run 4sA123 in my rustler through a sidewinder with no BEC now and havent had issues...

Sam

here you go

http://www.hobby-lobby.com/ubec.htm

[Sammus]

azjc: Yeah I since found it on amain too... but I'm weary to go and spend all this money on new noiselss BECs when evidence suggests that it isnt a noise related problem. Cheers anyway.

MTBT: Haven't got one.. I've been meaning to get one for a while. One day.

[QUOTE=Sammus;194405]azjc: Yeah I since found it on amain too... but I'm weary to go and spend all this money on new noiselss BECs when evidence suggests that it isnt a noise related problem. Cheers anyway.

MTBT: Haven't got one.. I've been meaning to get one for a while. One day.[/QUOTE

I have the Hercules HV model and I bought it mostly because I dont trust the CC model if it fails...it was $25 more than a CC and its good up to 60v

[Sammus]

If I get any itll be those dimension engineering ones that brian linked to before... I like the fact that the esc plugs through it, and also they only want like $1 for international shipping :P

[Sammus]

OK, so what do you think of this:

When I had the same problem with the Rustler, I took off the BEC and it all worked fine. I tried doing it with the Mamba Max (replacing the red wire in the esc lead) and the mamba max's internal BEC is working, the receiver powers up etc, I can use steering so it is getting signal, but no throttle! No beeps, just all the lights come on. I can't attempt to reprogram the Radio or anything, the esc just doesnt detect any signal.

Just to make sure I didn't wreck something somehow when I removed the BEC, I soldered it back one, removed the red wire from the esc lead, and everything is working again! Mamba max is detecting throttle input as usual.

Its been a year since the initial purchase, but it was only just replaced cuz I broke it before (paid $50 - that one was my fault). Here's hoping this new one is covered. to send it insured back to the states plus the repair fee is close to $80 USD, I can get a brand newwy for $100 delivered from bishop.

[RBMike]

This fixed mine:
http://www.amainhobbies.com/product_...ducts_id/20946

[Sammus]

Originally Posted by RBMike

This fixed mine:
http://www.amainhobbies.com/product_...ducts_id/20946

Thanks but I think its been made clear through several tests now that the BEC was not the issue.

MM is on its way to Kansas as we speak.