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[stallspeed]

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

That's what I said.
I know what the diode is for but I had Bluebird or Wombat in mind when I asked "where is it"
I was thinking the servo will tick by 1 degree (which is the finite resolution of a cheap servo) because it draws current through a diode drop.I was implying in an earlier post that this had nothing to do with the main problem and the conclusion that the servo and radio had problems were bogus.
The problem is the receiver voltage goes up and down like a yoyo and both Wombat and me have offered a solution.

[John W E]

http://www.action-electronics.co.uk/pdfs/P78.pdf

stallspeed have a look at the above link for your mystery diode

aye
john

bloobs

[stallspeed]

I was thinking the servo will tick by 1 degree (which is the finite resolution of a cheap servo) because it draws current through a diode drop.

There goes that theory into the dustbin.
over and out!

[BroomBroom]

The problem is the receiver voltage goes up and down like a yoyo and both Wombat and me have offered a solution.

And i do appreciate it - honest!
Just that when I proposed this plan of action, I was advised that the set up in it's current configuration should work - so I'm going to have a crack at seeing if I can get it to work this way first. Reason being: 1 - I won't need to mess about with the ESC (which has been proven to work perfectly as per FLJ's test rig and 2 - I'm trying to get it to run off 1 x Cell pack due to the nature of the beast.
Battery Pack incoming shortly!

Bear with me, I'm going to do one thing at a time or else my head will start spinning!

Cheers,

Robin

[stallspeed]

Back in again....
Yay!!!!!!!!

[John W E]

Stallspeed are you any relation Barry Park?

aye

[DickyD]

You were thinking the same as me John, dead similar isn't he ?

[stallspeed]

Sorry Dicky.
I must have have omitted you from the pm list when I changed last year

[John W E]

 

[OMK]

Quote from Barmy Park:

"...when I changed last year"

Post Moderated

Bob

[DickyD]

I thought so Barry Park, Sandy Calder, Phil Edison, Stallspeed all one and the same, wonder why he needs four identities, ***Moderated*** ?

[malcolmfrary]

Running an RX and a couple of standard servos should normally be perfectly OK off a set of AA duracells, assuming that all the components are in working order.  The problems start when the current draw increases.
The servo works by taking the length of time that the control pulse is on and turning it into a voltage.  This is compared with the voltage taken from its position sensing pot.  If there is a difference, the motor drives the position sensing pot to a matching position, at the same time turning the horn, and stops.
This derived reference voltage is a percentage of the servo supply voltage.  If this is caused to vary, the servo will try to drive.  This will put a load onto the supply voltage and cause a variation which will be seen as a demand to re-position.  Just one tiny twitch can start the thing interacting.
If the RX pack is supplying everything, use NiMH rechargeables.  Their voltage is less liable to sudden fluctuation.  At the same time, check out the lead resistance.  This can have the same adverse effect, for the same reason.

[BroomBroom]

Yup - Solved 100%

And the winners were - in no particular order... (roll of drums) - Bluebird, Craftysod, Stavros and FLJ.

My Solution:
Carefully remove anything with the word AC*MS written on it and blag an old Hitec Ranger2 - 27MHz outfit.

The Result:
Running on the same 4x Dry Cells as the old radio gear -- it works perfectly. Even with the boat so far away I can't actually see it - still perfect - not a single glitch anywhere. ESC works like a charm, Servo smooth and totally glitch free.

Yup, I will get a rechargeable pack - just pleased to get back to the modelling now.

So there you go - many thanks for the input - if nothing else I've learnt there's one particular brand of kit that'll never darken the portals of this boatshed again...

Cheers,

Robin

[John W E]

Hi there Robin

Glad you have your problem solved, but, sad because you had to acquire a new radio set 

You have solved the problem    but, like the rest of us - me in particular - some things have to be learnt the hard way - shame but there ya go 

If you had lived just round the corner, could have loaned you a radio set to try out.    Just for info another radio set which to have behaved 'iffy' for me - it the Sanwa Conquest at 40 mghz.   It's an 'old' radio set - but by hey it's given me some heartache.   The only I reason I used it, is because it's sentimental -bought it from a good shop when I was on my holidays first multi-channel 40 mghz I ever purchased - the rest is history and hard learned lessons  late nights, no hair springs to mind.

AYE

John