Servos .... booster or Rx pack ??

[lordnikon]

I'm having trouble with my core esc what appears to be shutting down and resetting with heavy servo and throttle use on 1s lipo. I've tried a capacitor in the rx which helped a little but not cured it.

So is the solution to add a booster in aswell to bring the voltage up or to run a seperate rx (life) battery pack ? I wanted to run the car on Sunday and am rapidly running out of time to order whatever is needed to sort it out.

Anyone add some options or give any other ideas, not sure what others are doing when running with a 1s on 1/12th

[levontraut]

hi m8

on the rx i am running a cap and on the lipo side the esc comes std with one of those bank things... this it like that i find the servo and motor do very well and i do nto get any brown outs.

what servo do you have in your car??

[lordnikon]

Hi, the esc has a couple of caps attached to the + and - accordingly.

I've tried a savox, bluebird and a cheap hobbyking one, ironically the cheap one runs perfectly, but is quite slow ! :(

I've ordered a couple of LIFe rx battery packs to plug straight into the rx and see if that sorts it. Fingers crossed.

[sosidge]

My suggestion would be to get a better servo. A Futaba 12th servo (eg 9650) would be ideal and is a long term investment that won't cause any troubles and won't need an extra rx pack.

[lordnikon]

Its 100% the servo's i have. I put a 6.6v LIFe batt into the rx directly and it all works perfectly. Ironically the cars were slightly under weight so this has balanced them up nicely :)

[mark christopher]

yup defo servo, futaba as sugested above!

[JimboJames1972]

Savox servos (especially the 1/10 scale sized ones) are famous for being thirsty on current. Sure, they are good value and have good specs, but they seem to achieve these specs by throwing current at the situation...

Futaba versions are more current friendly, but less friendly on the wallet.

Most speedos with inbuilt voltage boosting circuitry put out between 2A and 3A to the servo and receiver. However, some speedos are not always able to maintain a steady voltage to the receiver and servo if you push the currents close to their limits.

So, if you have the "wrong" combination of speedo with poor voltage/current output and a thirsty servo you will almost definitely get problems.

My suggestion is that a receiver pack might offer a better solution that a separate booster. Boosters only offer the same 2A to 3A as your speedo so adding one won't really get you any further. I'm guessing that a receiver pack can supply more? Just keep on top of charging it between racing and you should be ok.

Hope this helps,

James

[SlowOne]

What you have experienced is typical of not running an Rx pack or booster with a 1S cell through a '2S' speedo. Either a booster or an Rx pack will fix it. It seems the system will work without an Rx pack/booster, but the servo runs very slow.

Having a better servo will make no difference to this situation. You have done exactly the right thing by fitting the LiFe Rx pack. You could also try an RC Dynamic booster instead of the receiver pack, but since you've got that now... HTH :)

[mark christopher]

Pete think you got that wrong, the core Speedo that the thread starter has is 1s comparable and many have found on the fb group that they don't like power hungry servos.

[Gareth273]

Mark, what would you class as a power hungry servo?

[mark christopher]

Savox full size and low profile are worst, small 12th size are OK.

[reg]

Try running without the fan on to,that makes a difference,i run the small savox,with the powercap and no fan its fine with he Core speedo,i could be wrong but the spec on the power hungry ones state a speed at 6v and 4v or just 6v,the ones for 12th do 6v and 3v,dont quote me on theat though:)

[dale]

Try running without the fan on to,that makes a difference,i run the small savox,with the powercap and no fan its fine with he Core speedo,i could be wrong but the spec on the power hungry ones state a speed at 6v and 4v or just 6v,the ones for 12th do 6v and 3v,dont quote me on theat though:)

+1 to this.

Core ESC
Savox 1251 Low Profile Servo
Cap on receiver
No fan

Works perfectly. Without the cap it was useless.

[lordnikon]

Didn't think about the fan guys, worth a punt thanks !

[lardy37]

I know it might sound stupid, but what receiver are you using as I know a few guys at my local club had same problem when running savox servo with specktrum receiver and they had to use a really big cap to sort problem, I just put life battery in my sons and its fine

[reg]

I run a spektrum :)

[lordnikon]

Yeah spectrum micro rx with savox or bluebird servo

[SlowOne]

Thanks, Mark - my mistake. Yes, Savox and Spektrum is a bad mix, lots of forums have people saying that combo gives problems. No idea why since Savox seems to work with other receivers.

[Gareth273]

Hmm. May have to rethink getting my lad a Spektrum radio then.

[RogerM]

You'd probably be better getting a different servo, Spektrum stuff is very robust. I'd never put Savox in any of my cars no matter what the rest of the kit is.

If you want a cheaper servo look at the Alturn ones, if your willing to pay a little more than Orion do some very nice servos.

I will say I run Futaba and yes they are a bit more again BUT I have never, ever had one pack up on me.

[Gareth273]

I've looked into the Alturn low profile servo which for around £20 seems good value but it has a higher rating of than say a Savox sh1357 which is £35. Now is it an issue with the Spektrum rx using too much current or is it the servo?

[lordnikon]

Gareth, i have an alturn low pro and run it through spektrum stuff. It will cause problems with the fan plugged in on the core 45.

I have had results with the fan off and a large capacitor in the rx. However i have decided to put a 1000mah LIFe into the rx which has given better servo performance and seems a better solution. Minimal weight from the battery too

[mark christopher]

Hmm. May have to rethink getting my lad a Spektrum radio then.
gareth spektrum radio and rx are fine, fit a capacitor to the rx leave the fan off and use a savox 1350. all will be fine, its only the low profile or the full size servos that cause issues.1350 is a small 12th scale one

[SlowOne]

Like RogerM, I am firmly on Planet Futaba. Yes you pay more, but you get lots more. Very accurate and reliable servos, good performance and no problems with the radio. Always have a good resale value and are easy to sell. I have never had one pack up on me in 35 years racing, and the 9602s I had before going 2.4/HRS were ten years old and still going strong in the car of the guy I sold it to.

Which probably puts the curse on my servo at the Plymouth National, but since I have said that many times before I remain hopeful! :D

[KRob]

I too have found the Spektrum Micro receivers can struggle sometimes. I'll only run the micro when I have a low power servo in - otherwise I will put a standard size Spektrum Rx in as these do cope a bit better.