Motor cuts when steering?!

[Cardnim]

Setting up the Cat for oOple race and noticed that when I steer, the motor "stutters"

That is to say that it doesnt cut out but definately drops the revs for a short blip then comes back.
This seems to happen only when going slowly (or it might be that I dont notice the small drop when at higher speeds)

Any ideas what might be causing this?

[fidspeed]

the usual culprit tends to be a weak BEC in the ESC combined with a "large" current drain from the servo

the usual supects are savox servos and spektrum RXs ( not exclusively however ) reading similiar posts those two names crop up regularly

a power cap pluggesd into a spare RX port can help eliminate this

no guarantees on success

i have mainly spektrum rx and some savox servos and have occasionally suffered this ( running 1s lipo, spekky rx and savox servo is a deffo no-no and requires a lipo booster

Fid

[Cardnim]

Cheers FID.
I had suspected the BEC too, but hoped against that.

You're spot on with the servo - a Savox 1258TG
the ESC is a SpeedPassion GT2 (LPF)

Never used a power cap before. Are these an RC item available from shops, or is a standard capacitor of suitable rating?

[MiCk B.]

Hey,

Something like this is what you are after:

http://msdmodels.ie/zencart/index.ph...roducts_id=231




Receiver plug already fitted.

MiCk B. :-)

[Cardnim]

Mick - always there with a helping hand!!

Any chance of sending one over to oOple with Derek and the rest of the guys?
Will you see them before the race?

PM me if possible.
Ta muchly!

[fidspeed]

spektrum do them i think there about £6-7

the current drain by the servo causes the voltage to drop in the BEC supplying the RX ,causing glitches and issues (worst case is the rx switches off (known as a brownout and common in the RC aircraft world and has caused many a lost plane (personal experience ) quite often we run 5 cell rx nimh packs instead of 4 to keep voltage up when under load (using 4 or more digi servos in elaborate plane set ups )

fitting a power cap into the RX usually just boosts the voltage under high drain situations and helps eliminate problems

Fid