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[Seaspray]

Hi Mate

Have you tried to just power up the radio away from the esc and boat using the battery holder you have there. and try  operating the servo in the other channel on the Rx. If you've done this my appols as I haven't quite got the jist of this thread. I had this years ago, same brand of radio. It was the +ve part on maplin batteries that was shorter than th usual Unirooss ones and they moved away from making a full connectiion all the time. Another problem is with the battery box which I had to rotate the batteries once they were in situ till they made a good connection.Modelling in full of mysteries and when you solve the prob your on top of the world. Don't give up

Seaspray

[OMK]

I hate to be the bearer of bad news, but no amount of capacitors, silver foil, or even in-line chokes (when you discover what they are) will cure that problem.
In your last reply you have given three clues which weren't there in your first post. Three valid reasons why you will be forever banging your head against the wall with your present setup.
Fortunately, the answer is there already; you can glean enough info' from the clues, hints and suggestions from most of the replies.

[stallspeed]

With 1-battery operation,the receiver power supply has a pronounced alternating voltage(no longer smooth DC) only when you open up the motor throttle.On full power the current drain from the battery goes back to DC and the servo settles down.
   If you monitor a normal receiver supply, by scope, when moving a servo arm back and forth you see the ripples caused by the servo motor drain.
   If you monitor the voltage when driving the motor the supply trace goes apeshit.If you add chokes to the motor it goes back to something you get with a sail arm servo.

Chokes
A pair of something like these chokes http://www.maplin.co.uk/Module.aspx?ModuleNo=3660 but capable of taking the motor current should connect to the motor terminals .R.S. or Farnell do them.You can alternatively wind a pair of Ferrite beads for 6 uH 3 amp but that requires a calculation.

[wideawake]

Hi Rob

While i see from your comments that you don't have room in your model for two battery packs, I'd seriously suggest trying the system using a separate RX pack.  I'm reasonably sure that your problems are related to using the same pack.  I know it won't solve the problem long term but it will show whether or not any of the components are faulty as such.   If it is the combined battery pack then we can start looking for a cure rather than chasing a fault which may not be there.

I picked up a secondhand RTR electric boat a while ago at a club sale and it had more or less the same problem.   This was using my 2.4GHz gear which more-or-less eliminates most forms of interference being the issue.   As soon as I put the RX on a separate pack - problem totally solved.

Guy

[stallspeed]

Have the Duracells gone yet?
No?
Look at the resistance figure in the last graph of page 2 http://www.duracell.com/oem/Pdf/new/MX1500_US_UL.pdf
You will find four rechargeable cells make a difference over partially used alkaline as you take about 0.6 ohms out the supply resistance.

[wombat]

Right, I am probably gonig to add to your woes, old chap, but looking at the circuit....

You are running everything of the four dry-cells - not a problem but (you knew there was a but coming up didn't you)

One thing is that you seem to have the wire from the motor to the ESC in close proximity to the servo lead to the ESC - try separating them.

Also you seem to be running everything through those tadgy wires - not a good idea. It is quite likely that when the motor kicks into life, the voltage dropped in the wires goes up and this can cause the electronics to drop out and lose control. This is worse at the lower speed because the lack of back-emf and inertia in the armature makes the peak pulse current drawn by the motor higher.

Something to try...

Use the sortest possible wires for the motor to the ESC and ESC to the battery - 0.5mm^2 cable minimum. Route the power from the battery to the Reciever and servo separately to the power from the motor & power section of the ESC.
 
Wom

[stallspeed]

Where is that diode and what does it do?

[BroomBroom]

Thanks so much for all your efforts guys!

So, I'm thinking that first I have to try powering the ESC from a separate battery pack then... great - that means that I have to rip the diode out of it? If that solves the problem, well I don't know what to do - no room for another battery pack - how come the ESC is available in this configuraton if it apparently is never going to work?

Sadly, It'll now have to wait a bit if I need to get 2 x 4xcell battery packs and charger - all getting too expensive for something that was supposed to be a bit of simple fun - are these really that essential?

Assuming that sorts it, the problem is then that I'll have a cute wee model and a working system that won't fit it - makes the whole excercise rather pointless...

Sorry, but I'm getting utterly disheartened with this - done loads of RC aeromodelling in the past with IC engines and never had a single problem - i'm surprised that the technology required for such an apparently simple set-up is so flakey.

Feeling very negative at the moment - but hey-ho I won't be beaten (I hope) and really appreciate the help you have all provided.

Cheers,

Robin

[BroomBroom]

Where is that diode and what does it do?

It is in the ESC enabling it to run in its "straight through" mode i.e. using the same battery for the receiver and motor. This was recommended for my set-up. Use of an external powerpack negates the need for this.

Cheers,

R

[stallspeed]

Graupner Speed 280 6V (6328)
A small, powerful motor for the smaller model boat.

GRAUPNER SPEED electric motors are equally well suited for model planes, boats and car applications. The nominal operating voltage is in each case marked on the motor case for ease of identification.

Specification
Nominal voltage 6 V
Operating voltage range 4,5-6 V
No-load rpm 14000
No-load current drain 0,275 A
Current drain at max. efficiency 1.58 A
Current drain when stalled 6.8 A      <<<<<<
Max. efficiency without gearbox 58,2 %
Length of case, excl. shaft 30.5 mm
Diameter 28.8 mm
Free shaft length 11 mm
Shaft diameter 2 mm
Weight 42 g

Did I say what you had was similar to a quarter scale servo?
Robin,since you have to change the batteries in the long run can you just please humour me and see what difference four rechargeable cells makes.It won't cure the problem but it will reduce it by an order of magnitude.
You are capable of  V = IxR calculation
The I comes from above and R from the red line graph on page 2 of the Duracell pdf link indicates 0.15 to 0.2 ohm per cell when they are 30% depleted.You have that voltage superimposed onto 6 volts.
Changing battery and putting two small components onto the end of the motor will transform the  results.

[Seaspray]

Its getting too complicated now. Firstly the little batteries won't be up to the job for long having to power everything and the motor will steal the power from the radio, leaving a half dead boat out in the water. Seriously consider a MI-MH battery pack for the motor running only and the current battery holder for the radio. Usually if I have a jumpy servo the Tx just needs to be trimmed but this is mostly on the cars as you have to tune the ESC to the stick swing on the Tx.

Here my set up after years of trial and error Ni-cad 8.4 pack for the motor and 4 AA Ni-cads in the holder for the radio. Notice how everything has at least a few inches away from each other. The items have been pulled out of the sitting positions to let you see them.The ESC is one of the best I've ever bought and have lost the address of the chap whom supplied it.
Seaspray

[BroomBroom]

The board that never sleeps...

Yup, next stage is to run the ESC from a separate, re-chargeable supply... now if I can find one that uses 4xAAA size cells 

Will keep you posted!

R

[Stavros]

Component shop for all your rechargables address in traders list


Just remeber that Dave at Action has set up your esc to run the motor off the batt pack so suerly you wont be able to use a separate pack with that esc,and also I have had a similar problem with Acoms gear now I only use Futabe



Stav

[FullLeatherJacket]

Gentlemen
Before you drown this poor guy in a sea of hyper-technical speculation – and before I get more annoyed about having our products’ supposed shortcomings aired in public – I have just conducted a test of a typical set-up as follows:
Tx – Hitec Ranger 3 40MHz FM
Rx – Hitec HFS-04MI 4 channel 40 MHz Single Conversion Rx
Servo – Hitec HS55
Battery – 4 x Vapex 2400 mAH AA NiMH pack
ESC – Condor 2A, running in “straight-through” mode. Motor wires are 22AWG silicon, as supplied to Robin.
Motor – Stock (Chinese?) 280 clone, with 0.1uF ceramic disc capacitor across the brush terminal connections.
The aerial wire on the receiver has been cut down to approx 150mm, with a 1mm Wander socket on the end intended to mate with a plug fitted to the whip aerial connections in my models (so it has the effect of reducing the range when no whip aerial is connected).
I ran the set-up for five minutes, moving from full reverse to full ahead slowly & quickly; moving the motor stick just to each side of neutral – so the motor was running at very low revs - and all the time leaving the rudder stick alone as well as operating it.
I could not see any trace of servo stuttering or motor glitching. Both functions operated smoothly with no cross-talk etc. In short, everything performed exactly as it should. The items tested were a totally random selection from our stock of ESCs and motors.
That’s the facts – not conjecture or opinion. Please feel free to draw your own conclusions, but can we move on, please?
FLJ
(......and, yes - the batteries did come from that supplier, Stavros!)

[BroomBroom]

Dave, thanks for the input and taking the time to rig this up and test it at your end - appreciated.

1. Never had any doubts about your ESC - does exactly what it says on the tin  - PERFECTLY

2. Your test rig demonstrates that a configuration precisely the same as mine also works perfectly.

3. I will get an order in to those guys for a rechargeable pack - even though I don't think it will make any difference.

4. The conclusion I have to draw from the FLJ test rig is that at least part of my Radio gear is total pants.

I'm not sure which part - should I start by swapping out the servo / then the receiver if that doesn't do it?
If so, can I use a different manufacturers servo with the rest of my gear?

Finally - am I going to regret asking this last question? If so I might just stick some pencils up my nose, rock backwards and forwards and say 'Bibble' a lot...

R

[Seaspray]

if I was in this position now. I would take the boat and gear down to the local boat club near me a.s.a.p. There is always somebody there that could help.

[wombat]

4. The conclusion I have to draw from the FLJ test rig is that at least part of my Radio gear is total pants.

I'm not sure which part - should I start by swapping out the servo / then the receiver if that doesn't do it?
If so, can I use a different manufacturers servo with the rest of my gear?

Hi there dude,

Before you start scrapping stuff, I would try sorting the wiring out - this is where I see the weakness in your setup. Even the battery should cope if you are running out of the water, though NiMH cells will be better (and cheaper in the long run)

Wom

[wideawake]

Just to clarify, nothing I've written was intended or should be taken as suggesting that the Action ESC was at fault.   I use and have a high regard for FLJ's products and customer service.   As someone who in the distant past was an electronics engineer, my suggestion of trying a separate power pack for the RX was based on the logic of eliminating the easy things first!  My training taught me to try the easy things first, to only change one thing at a time and to restore to square one after each unsuccessful attempt.   In an ideal world (or the world of TV I worked in) we'd usually have another identical bit of kit alongside so we'd swap boards and see which way the fault went!    You'd be amazed at how many faults were due to dirty connectors and didn't show on either unit once swapped due to the fact that they were just due to dirty conectors.

Guy

[John W E]

hi all

Just to put the cat amongst the pigeons, this is a very similar set up to what you have, where its an ACTion speed controller, running off the same powerpack as the RX.

If you notice, the motor IS NOT suppressed; and there is no 'glitching' whatsoever on this model when I run it on 27 mghz or 40 mghz.   It has the cheapest of cheap mini-servo in the back end for her rudder and she has a cheapo scrap motor from a cassette drive in it.

The first transmitter I used was the Futaba 27 mghz Attack Sport - and then I went to SkySports 4 x 40 mghz transmitter and receiver. 

The only problem I have with this model is the actual run time - that is because the battery pack is a 4.8 volt x 600 mah thing.   I need to increase the mah and not the voltage.

So, I believe your fault may be in your transmitter/receiver set up that you have - Acoms are not the best in the world.   So, to me, I feel it may pay you to change your RX receiver to either a HiTek or a Futaba one and that way you should get better results.   Good luck with that.

aye
john

[Peterm]

As said in the previous post, get another make of receiver, but whichever you get, make sure you have the same make of crystals, as they are not all compatible.   Pete M

[stallspeed]

The ESC is one of the best I've ever bought and have lost the address of the chap whom supplied it.
Seaspray

The website URL is on the other side of esc.
www.modelboatmayhem.co.uk/forum/index.php?topic=13738.0

[Seaspray]

Cheers stallspeed

For the address. I also printed out the setup procedure and the site address. I also got a lot of help sometime ago from this chap. I believe he is a member

This controller is the best

Well lads I'll be going back into hibernation as i need all the time to sus out this next crane build for the Meteor.

Seaspray

[John W E]

Hi all

now Ive had time to have me dinner and think and re-read original posting by Broom Broom 

he states 'when he plugs the servo in by itself to the RX along with the power supply, the servo 'ticks and judders' slightly for no reason'

now then...

in the past I have had this happen to myself on servos, when the servo has been a very old one which had been contaminated with fuel from an IC engine and which fuel has found its way into the variable resistor pot   or   

the other case was when I had a mis-match and I had reconfigurated the wires from an 'old'Sanwa servo to fit a modern day Futaba receiver;

The first problem I had with the fuel contamination in the first servo I cured by cleaning the servo out; and also the variable resistance with WD40 and then washing out with methylated spirit.

The 2nd problem , I could never cure because the servo used to just 'twitch' away and it was a mismatch.   The problem became worse when I added any other servos cum speed controllers to the RX receiver. 

Can you see where I am coming from here...I would be willing to put a 10 pence piece wager  that the Broom Broom's problem has nothing to do with the speed controller battery voltage being either dry cell or niCad or wiring/suppressing.

The fault, I believe, lies in the servo and the Rx.  Something Broom Broom has no control over, unless he may access temporary replacements for try out.

Plus, Broom Broom, if you can lay your hands on an 'old'Acoms servo - why not strip it down, removing the gearing and use the motor and electronics from the servo (the electronics as a speed controller and the servo motor to drive the model) same as the plastic-magic lads do.   See if the fault is still there.

aye
john e
bluebird

[stallspeed]

The small ticks,without motor,may be down to the mystery diode but you know where it is,I don't.
Oh!, I agree with you that the present set up can work.That makes three folk! ......but
....as I said in an earlier post,with a small e.g. cassette motor,which is usually internally suppressed to work in proximity to a radio, and does not have the stall figure of a speed 280............. and with NiCDs which don't drop 0.5 volts per cell with a 3 amp draw.

Sail arm and winch servos have motors approaching the power of the 280 but the one I have have single ended chokes to the motor.

[BroomBroom]

Cheers John!

Latest position is I now have a new HiTec 40MHz AM Rx incoming. This will (allegedly) work fine with the rest of my gear. So I'll drop it in when it arrives and keep you all posted.

If that doesn't do it, then I'll swap out the servo.

Stallspeed - mystery diode is in the ESC to allow it to operate in 'straight thorugh' mode - nope, ticks away even without the ESC hooked up.

Cheers,

Robin