Stuttering question....

[captainlip]

I have just spend 2 hours soldering my noram esc completely and motor, all is well and im insanely happy but there is one problem / adjustment ?

if you wiggle the steering when idle it causes a sudden stutter of the throttle :eh?:

same if your moving if you wiggle about do a few twists and turns there is a notiable stutter in the power.

sensor lead is fitted fine, any ideas?

[markwilliamson2001]

Is it a 7.2v servo per chance? Did you fit a choke between the fet lead and ESC?

Otherwise is your speedo capacitor working okay? Is that soldered up okay?

Let us know some more info:)

[captainlip]

Is it a 7.2v servo per chance? Did you fit a choke between the fet lead and ESC?

Otherwise is your speedo capacitor working okay? Is that soldered up okay?

Let us know some more info:)

believe its a 7.2v its a savox sc1258. not sure what you mean by a choke but i dont think there is one.

soldering is a great job took lots of time over it. and the cap is soldered nicely working fine. its just when rapid steering weaving it stutters slightly, not massive problem but want it sorting non the less.

[markwilliamson2001]

That servo is 6.0v...according to savox website. This means you dont need a choke.

Only other thing is to move you receiver as far as possible away from the centre prop..it could be electrical noise effecting the receiver. Are you running 2.4Ghz or 40Mhz? Upgrading to spektrum will help. If your already running spektrum, try getting one of the capacitors that plugs into the receiver.

Cant provide much more help without looking at the electrics install in your car. Can you upload an overtop view of the car?

Cheers
Mark

[captainlip]

That servo is 6.0v...according to savox website. This means you dont need a choke.

Only other thing is to move you receiver as far as possible away from the centre prop..it could be electrical noise effecting the receiver. Are you running 2.4Ghz or 40Mhz? Upgrading to spektrum will help. If your already running spektrum, try getting one of the capacitors that plugs into the receiver.

Cant provide much more help without looking at the electrics install in your car. Can you upload an overtop view of the car?

Cheers
Mark


I believe it doesnt have a choke, running 2.4ghz the aerial is running across the top of the esc passing all the wires and lipo wires. got a spektrum in at the mo and will be getting a dx3s shortly.

what does the capacitor do on the reciever?

[paulc]

Why is the aerial running over the esc ? post pics ?

[captainlip]

Why is the aerial running over the esc ?

because in the rango the reciever is by the spur and the aerial is in the front, thus having to pass the esc directly through the wires as the aerial is quite short its the only route.

[ianhaye]

can you not swap the rx and esc around so areal doesnt have to run over the esc? also try anothe servo, a dodgy servo can also cause these probs, mine even made my esc shut down sometimes.

[i4n]

Move the receiver/aerial away from the ESC (general rule of thumb, keep the aerial as far away from the 'power' electronics as possible).

The power capacitor smooths out any possible dips in voltage to keep the receiver powered up that you may get under hard acceleration. I had problems with what I thought was interference and it was this, always run one now and no problems. You can buy them from Spektrum or make them up yourself (there's instructions on oOple somewhere if you have a search).

[johnb]

I've had the same problem with a Lrp tc sphere speedo if you turned the steering left or right it would make the car stutter and lurch forward.
I only ran this speedo from new with a power cap fitted and a Futaba 2.4 receiver and Savox 1258 servo. And tried to move the receiver around the car and re-route the wiring so nothing touched but would cure the problem for a heat or two but still would come back again.

But then two weeks ago it got to the point where if you turned the steering the car would drive forward without me touching the throttle. And the only way to stop it was jamming on the brakes so checked all my settings on the radio and all okay so thought it had to be the speedo so gave it a run in practice and that's when I got the smell of burning and since then I've taken the speedo apart and near the fet's there's a small part that's burnt out so guess that may have caused the problems to start with or something else has caused it to burn out.

Since then I have put a speedpassion speedo in the car to check to see if it wasn't the radio gear at fault and no problems what so ever.

So may be worth trying a different speedo or getting someone to check the speedo out to see what the problem maybe.

[paulc]

can you not swap the rx and esc around so areal doesnt have to run over the esc? also try anothe servo, a dodgy servo can also cause these probs, mine even made my esc shut down sometimes.

Move the receiver/aerial away from the ESC (general rule of thumb, keep the aerial as far away from the 'power' electronics as possible).

The power capacitor smooths out any possible dips in voltage to keep the receiver powered up that you may get under hard acceleration. I had problems with what I thought was interference and it was this, always run one now and no problems. You can buy them from Spektrum or make them up yourself (there's instructions on oOple somewhere if you have a search).


As these guys say also if your running a pt to close i have had this problem with Savox servos but no other brands

[captainlip]

had a quick look over it this morning and i had to resolder the on off switch as the + and - were touching a few fiddles and the car wouldnt turn off, tidy little solder job later and its fixed.

not stopped the stuttering though. moved the aerial and this was to no avail. tweaked through the odd setting and still no change. you can feel it when driving.

but main time it happens in when idle IE no throttle. :eh?:

[johnb]

That's what mine started doing at first as when you had the car on the table in front of you or you when to put it down for racing to test the steering the car moved forward but got to the stage that you noticed it when racing that the car wouldn't slow down or come to a halt when off the throttle.

I tried with moving the pt to a different place as thought might be getting electrical interference but still did the same thing.

And unfortunately got to the stage where the speedo burnt it's self out.

So don't know what the problem was with mine but since changing the speedo it's all been fine.

[captainlip]

I have just ordered a voltage protector and will try another servo tomorrow.

[captainlip]

ok today I tried a ko pro servo I have thats spare, and with this fitted there was not one glitch, soon as I put the savox on it stuttered again, tried 3 times and the same thing, really odd as the savox is new and no issues with the SP system I was running just with the nosram, could it be savox and nosram dont like each other?

as im selling the savox now as its no good for me what other top brands should I look at? ko pro as this spare worked perfect? or ace servo?

[captainlip]

I've had the same problem with a Lrp tc sphere speedo if you turned the steering left or right it would make the car stutter and lurch forward.
I only ran this speedo from new with a power cap fitted and a Futaba 2.4 receiver and Savox 1258 servo. And tried to move the receiver around the car and re-route the wiring so nothing touched but would cure the problem for a heat or two but still would come back again.

But then two weeks ago it got to the point where if you turned the steering the car would drive forward without me touching the throttle. And the only way to stop it was jamming on the brakes so checked all my settings on the radio and all okay so thought it had to be the speedo so gave it a run in practice and that's when I got the smell of burning and since then I've taken the speedo apart and near the fet's there's a small part that's burnt out so guess that may have caused the problems to start with or something else has caused it to burn out.

Since then I have put a speedpassion speedo in the car to check to see if it wasn't the radio gear at fault and no problems what so ever.

So may be worth trying a different speedo or getting someone to check the speedo out to see what the problem maybe.


funny you say that as im running the same servo, banged on a ko propo servo and dont have a problem with it, and the savox ran perfectly with the speed passion system, i wontder if it is a problem with pearl/sxx and savox servos?

as there is no glitching and stuttering with the ko propo servo, so it cant be the speedo? :bored:

[johnb]

Yeah I was wondering if there is a problem with Lrp/Nosram speedo's and Savox servo's as did try an old Sanwa servo and worked okay for a bit but the problem did come back so could be issues with certain makes of speedo's and certain servo's and there not all truly compatible.

Good to hear the speedo is okay and working now.

[discostu]

its unlikly to be a compatibility issue with the servos it sounds more likly to be a fault in the bec circitry in the esc its also unlikly to be a voltage issue to the reciever as we use nominal 7.2volts and most modern servos run at 6volts which is regulated from the esc the capister unfortuantly was a waste of money.

the capister that spextrum intriduced was to stop the recivers shutting down when running fast mods on nimh batterys and all it does is store energy for a short period so when a low voltage situation accured momentarly the rx wouldn't shut down.

again look at your instalation is your pt next to rx is the rx next to the power wires is the rx next to the esc capasiter.

i ran savox with nosram pearl for a good year with no issues.

stu

[captainlip]

the savox constantly brings on the blue limit light when flicking the tranny wheel.

bang in an old ko propo and the blue light doesnt come on once, ive got my savox apart now to check the soldering I did when I shortened wires but all looks well.

the cap on the esc is between the motor and esc and the rx is not touching the cap.

the ko servo feels so much smoother even driving the throttle no stutters or jumps. but the ko has seen better days hence is a spare so looking for a new servo if this savox is no good

sorry for the noobness but what is the px? :p

[discostu]

rx=receiver
tx=transmitter
pt=personel transponder
cap=capasiter
lipo=lipo battery
nimh=nickle metal hydried battery
nicd=nicad battery

durango=the unfortunate lump of alu housing a load of radio equipment garanteed to give trouble. LOL Just kidding its a pretty good car.

stu

[captainlip]

super thanks, I dont run a PT with these issues.

[paulc]

I've been running LRP esc and Savox servos most of this year without problems. I did have some glitching when i mounted the PT on top of the servo moved it away from the servo it was all fine :)

Paul

[captainlip]

nothing near the servo as its right at the font away from esc. the only thing close to each other is the rx aerial this runs over the esc but has cause no issues, the ko servo works perfect no glitching, but I need a better condition servo for my new rango :lol:

will sell the savox as get another servo, not sure which tho

[discostu]

like i said look at instalation you say your rx aeiral is over the top of the esc this canot be good as its a lump of alu attached direct to about 25 power fets all producing electrical static you will probably find the ko servo is anolge and the savox is a digital servo which will be more prone to electrical interferance post some pics of the layout. im struggling to see why you need to run the rx areial over the esc.

stu

[paulc]

Ace 1015 fit and forget :thumbsup:

[paulc]

Why do you need the reciever on that side so the aerial has to go over the esc ? i'd take all the electrics out the car and try them see if it still happens

[Whiskers]

Which receiver are you using?

[captainlip]

a spekky!

as in my other thread could it be the fact the savox is digital its the reason its causing this issue? the ko is analogue and no issues at all, really smooth.

[Whiskers]

Just ordered my DX3S from JE Spares and also a receiver cap so I hope I don't have any of these issues!

[coolcars782]

I run a Savox and A spektrum DX3S with a SR300 and a SR3300T Rx and a Novak GTB esc, nothing wrong with mine, not running a power cap either.

[captainlip]

well i have a problem and it needs sorting but have had very little useful information.

[johnb]

I think there is a problem with the speedo as in my previous posts I've had exactly the same problem as when you flick the steering left to right the blue light comes on the speedo and the car lurches forward.

It could be the Savox servo making the problem worse as tried both my 1258 servo's and still had the same problem but did try my old Sanwa and it did cure it for a bit but the problem did return so not an expert on electrics so don't know if there may be some interference with using the Savox.

So might be a good idea to send it to Nosram or who distributes them in the uk to find out if it's working okay and see if there may be a problem as eventually my Lrp burnt out.

[captainlip]

hmm not happy as the seller was insistent that there was no issues with it when it was sold, the wire from the esc to rx is tatty looking and as the soldering was poor on the on off switch this could be the case in the esc

if the cap does nothing then i will open up the esc and look at the soldering maybe put some fresh cable on that I have.

other than that I wont be happy. but can only keep trying everything points to the rx losing voltage.

[Steveonamission]

hmm not happy as the seller was insistent that there was no issues with it when it was sold, the wire from the esc to rx is tatty looking and as the soldering was poor on the on off switch this could be the case in the esc

if the cap does nothing then i will open up the esc and look at the soldering maybe put some fresh cable on that I have.

other than that I wont be happy. but can only keep trying everything points to the rx losing voltage.

And i'm sorry to say i still am insistent, i never have sold anything that wasnt in perfect working condition and never will, sold quite a few escs on here with no trouble what so ever....... I ran the Nosram Pearl for must of been 50+ 5 miute TC runs, without any trouble. Equipment being a KO Universe 3 40mhz (302f reciever), Sanwa 801 servo, and either a 4.5 or 10.5 X12 motor in TC.

Have you tried another digital servo? It could be a number of things, thats interfereing......seeing as it works with another brand, but havent read that youve tried another digital...maybe borrow a friends, instead of having to shell out.

[DCM]

Firstly, the cap on the Spektrum receiver is only there to stop it shutting down due to voltage spikes.

You need to pull everything out of the car, spread it on a desk and try it, if it still glitches, then you need to look at wires etc, but until you resolve that it isn't an 'installation issue' your pissing in the dark.

[chris_dono]

a spekky!

as in my other thread could it be the fact the savox is digital its the reason its causing this issue? the ko is analogue and no issues at all, really smooth.

Which radio are you using ? On a futaba 2.4 for example, you can use an analogue servo on ppm/pcm but a digital one will need the radio to be put into hrs mode, perhaps you have a setting for it but it's still on the analogue one ? (depends on your tx of course)

[captainlip]

Already stripped it out and still the same

Using a dx3s that im borrowing until i get my dx3s

[captainlip]

And i'm sorry to say i still am insistent, i never have sold anything that wasnt in perfect working condition and never will, sold quite a few escs on here with no trouble what so ever....... I ran the Nosram Pearl for must of been 50+ 5 miute TC runs, without any trouble. Equipment being a KO Universe 3 40mhz (302f reciever), Sanwa 801 servo, and either a 4.5 or 10.5 X12 motor in TC.

Have you tried another digital servo? It could be a number of things, thats interfereing......seeing as it works with another brand, but havent read that youve tried another digital...maybe borrow a friends, instead of having to shell out.

Sorry steve im not implying that you sold a dodgy speedo ive spent 10+ hours trying to resolve this and im pissed as ive tried alot bought a power cap as was advised to then other people saying take it all out and others saying stuff ive already tried as they havent bothered to read the whole thread, i just dont get how nobody has a defantive answer to this. All points to the savox drawing to much current causing this glitch.

[discostu]

Sorry steve im not implying that you sold a dodgy speedo ive spent 10+ hours trying to resolve this and im pissed as ive tried alot bought a power cap as was advised to then other people saying take it all out and others saying stuff ive already tried as they havent bothered to read the whole thread, i just dont get how nobody has a defantive answer to this. All points to the savox drawing to much current causing this glitch.

have you tested the currrent draw of the servo and tested to see if the voltage drops when moving the servo left and right if not i would do this first then you will no for sure. if it was me i would measure both your ko servo and your savox and take note.

stu

[captainlip]

yes im my other thread the rx voltage on the monitor drops to 6.3v 6.1v and sometimes as low as 5.2v for a split second

[Whiskers]

What have you got your fail-safe positions set at because it could be the fail-safe kicking in when the voltage drops and if it is set to throttle then it would cause the motor to run.

[captainlip]

What have you got your fail-safe positions set at because it could be the fail-safe kicking in when the voltage drops and if it is set to throttle then it would cause the motor to run.
100% brakes

[Whiskers]

So when you turn the transmitter off before the car it goes to full brakes?

[captainlip]

yup!

[Whiskers]

Damn! I thought that might have worked seeing as nobody else has mentioned it.

[discostu]

yes im my other thread the rx voltage on the monitor drops to 6.3v 6.1v and sometimes as low as 5.2v for a split second

that seems ok to me you could use a cap to take out the split second voltage spike what current does the servo pull is within the manufactures limits it could just be faulty

[captainlip]

the motor only stutters when this voltage drops, servo works fine otherwise

[bodgit]

Have you ran the car at all yet.

[discostu]

the motor only stutters when this voltage drops, servo works fine otherwise

ok if the servo is pulling to much current the voltage drop the reciver power drops the esc gets strange signals from reciever as that is the piece of equipment what tells the esc what to do all the reciever uses the esc for is power 6vDC.

what you could try is attach reciver pack to the reciver and see if the problem is still there this way the reciver will be getting a clean 6vDC with a higher current range you may find the servo is fine but the bec curcitry in the esc isn't allowing the current to be drawn.

if ther problem is till there i would almost certanly change the servo.

stu

[captainlip]

ok if the servo is pulling to much current the voltage drop the reciver power drops the esc gets strange signals from reciever as that is the piece of equipment what tells the esc what to do all the reciever uses the esc for is power 6vDC.

what you could try is attach reciver pack to the reciver and see if the problem is still there this way the reciver will be getting a clean 6vDC with a higher current range you may find the servo is fine but the bec curcitry in the esc isn't allowing the current to be drawn.

if ther problem is till there i would almost certanly change the servo.

stu


and if that solves it whats the soloution?

[sparrow.2]

On the off chance that you haven't tried this yet. Set everything up, turn it on, turn on your transmitter and then take 5 steps back with the transmitter.

My Spektrum receivers do not like having the transmitter anything closer than about 3 feet.

If this works you are in for a big "DOH!" moment :)

[captainlip]

yes same even with it 20 feet away

could it be that im using the lrp sensor wire and not the nosram?

im really running out of ideas :cry:

[discostu]

and if that solves it whats the soloution?

if it solves the problem it can only be your esc bec circitry the solution would be a differnent esc or a less power hungry servo.

stu

[sparrow.2]

could it be that im using the lrp sensor wire and not the nosram?

No, they are essentially the same thing.

Really reaching now but have you maybe got channel mixing activated in the transmitter? All setings for the throttle travel set to 100%?

Have you tried setting the response time in the transmitter to the slowest setting?

Have you recalibrated the speedo to the transmitter?

Is the servo jamming at the end of the travel? (does it buzz and try and travel further than it physically can when the steering is at max) - This could cause it to draw serious current and get hot too.

[captainlip]

yes all done, how about if i do a master reset of the transmitter

[bodgit]

Assuming you havent run it outside yet where are you testing it?
A few years back I had similar problems while pitting in the utility room, Turned out it was picking up interferance from the washing machine, and fish tank pump. Once it was outside in the garden all was well.
If your near any electrical source that could be your problem.
Also you say you took ages soldering in a new lead. If you left the iron on more than 2-3 secs the heat transfer could have damaged internal components in the servo.
Can you test it in another car?

[captainlip]

Stripped the servo with no signs of any problems

Ive used it in a large open area about 30ft with no electrical eqipment in sight

Every single time i google this problem and trust me ive done it many times all the forums im reading all point towards the cap ive ordered

[captainlip]

No, they are essentially the same thing.

Really reaching now but have you maybe got channel mixing activated in the transmitter? All setings for the throttle travel set to 100%?

Have you tried setting the response time in the transmitter to the slowest setting?

Have you recalibrated the speedo to the transmitter?

Is the servo jamming at the end of the travel? (does it buzz and try and travel further than it physically can when the steering is at max) - This could cause it to draw serious current and get hot too.

servos not jamming at all.

responce is on 11ms

[captainlip]

looks like having everything crossed has paid off! :woot:

problem solved with power cap fitted, no glitching at all now and has been extensively tested.

turns out savox draws to much current from the RX causing the RX to send the odd signal to the esc. :thumbsup:

just in time for racing this weekend

[discostu]

glad to here its fixed.

stu:thumbsup:

[captainlip]

thanks stu! and thanks for your input! :thumbsup:

[Whiskers]

How many times did we say you needed a power cap?! I'm glad I ordered one now!!

[discostu]

i just checked the nosram esc is rate at 6v/3amps the savox servo is rated at 6v but it has a stall current of 5000mah (5amps) now just to clarify your problem is only happening when you go from lock to lock or under load and i would hazard a guess the its glitching at that point because the amp draw is above 3amps.

what you may find if you put your exact setup in a tc with no cap you would have never had a problem because the whole steering mechanisme (including Wheels) is lighter so it would need less current to move every thing.

like i said previous its good you fixed the problem and i hope this clarifies a few things for everybody.

stu:thumbsup:

[captainlip]

How many times did we say you needed a power cap?! I'm glad I ordered one now!!


already had it on order just waiting for it to arrive

[captainlip]

i just checked the nosram esc is rate at 6v/3amps the savox servo is rated at 6v but it has a stall current of 5000mah (5amps) now just to clarify your problem is only happening when you go from lock to lock or under load and i would hazard a guess the its glitching at that point because the amp draw is above 3amps.

what you may find if you put your exact setup in a tc with no cap you would have never had a problem because the whole steering mechanisme (including Wheels) is lighter so it would need less current to move every thing.

like i said previous its good you fixed the problem and i hope this clarifies a few things for everybody.

stu:thumbsup:

sounds about right stu! though it still stuttered in the air with little resistance.

anyways I dont care anymore. :D strange its not happened more! :bored: there was information to be had online but not on this forum

[Whiskers]

already had it on order just waiting for it to arrive

I know the feeling but you didn't seen to want to wait for the cap to arrive by the amount of things you were posting on the various threads! :woot:

[captainlip]

its was because i was getting so many different suggestion on here, its not like everyone was pointing towards one thing, I was wanting it ready for sunday to. :D