TOPIC:

having recently dragged my original grasshopper out the attic i am in the process of getting it back up and running, the mechanical stuff i can cope with but i am losing the plot when it comes to the electrical side of all the servos and controls? upgrade to ESC or try and salvage the original.

the speed controller i got from ebay but it is from a hornet. it fits and works but it has a little red plug on it with tiny black and red wires. i cant figure out where it goes?
i am wondering if it is possible to remove the 4 x AA battery pack in the rear which i think supplies the reciever unit as i need to remount the receiver behind the speed controller (as stated in the tamiya manual), to make fitting the battery easier. but i cant seem to get it to fit

here is a couple of pics, the new shell and the battery followed by the car, with new speed controller fitted and all new steering components.



Post was modified with the purpose of merging two threads.
Thanks @agemax for starting the new topic.

Looks like it's in a really good condition. Even the tyres don't show much wear.

If you get an electronic speed controller with a BEC (or if the receiver has one) the power for the receiver can come straight from the ESC/battery pack and the battery holder can be removed.

A BEC is a voltage limiter to avoid the 7.2V from the battery that drives the car going directly to the receiver.
Receivers usually work with about 5V so the direct feed from the pack will be too much.

I am not sure why you wouldn't be able to fit the Rx in between the servo and the MSC...


Maybe it's a bit too big - nowadays they are a lot smaller.

An ESC will save a lot of room and also weight. One of the servos can be removed too!
But most of all (like Jonny Retro already mentioned in your introduction topic) it will avoid your car from ever running wild.
I would recommend an ESC that also has a failsafe feature.
That way the car shuts down when there is interference in the signal.

Had to learn that the hard way with my own Grasshopper...

agemax wrote:

the speed controller i got from ebay but it is from a hornet. it fits and works but it has a little red plug on it with tiny black and red wires. i cant figure out where it goes?

I can't identify them on the picture but they are not an essential part at least.
Guessing they could be connected to an on/off switch...

Or more likely an external feed if you have the right receiver!
You could try measuring the voltage with the battery plugged in if you have the tool for that.

the little red plug is just to the right of the steering servo. it is soldered directly to the battery cables on the underside of the speed controller, so im guessing it would be 7.2v

Yes, I put on my glasses and see it now.

If you're not going for the ESC, I think that with a BEC cable you could feed the receiver with this.
Since it probably doesn't have one... but could you tell us the brand and type?
I could check if there is any info on it.
Also curious what the little red plug looks like exactly...

One more time for the ESC - it would really look nice and tidy on the car.
Stuff you could leave out :

- battery holder and batteries
- servo for MSC
- the MSC itself
- the resistor on the back
- fuse box
- on/off switch
- a whole bunch of wires

ok, the receiver is ACOMS IC receiver, ARC-227 2 channel msystem.
the speed control servo is ACOMS ICas-5s
the speed controller i bought is a TAMIYA TT-01 shaft driven 4wd speed controller set(1050206).
if you look at this ebay item no.170698368329, it looks the same speed controller and you can see the little red plug more clearly. (mine was brand new)

I can find the specs from the Mk3 of the receiver and it operates between 4.8-6V. No BEC.
A power feed from a sixpack battery would likely destroy it.
Five batteries could work though but that doesn't seem like the most logical solution.

I'll check out your item number and also for a link to a BEC cable for example.



More of a mechanic myself but I'm thinking it's actually a BEC connector!

This should do the trick I think but then again for that you're almost halfway from a decent ESC...

ok i am starting to get a bit confused now between BEC's and ESC's etc.
can someone please explain these in laymans terms.
i will try to run through the whole wiring on the car as best i can.....

4 AA bateries go to a switch, from the switch it goes to the receiver.
from the receiver, 1 plug goes to the steering servo,1 goes to the speed servo.
the main battery plugs into the speed controller, 3 little wires go to a resistor and 2 wires go to the motor,through a fuse.
also the elusive little red plug from the speed controller that seems to go nowhere

Sorry to overwhelm with the abbreviations - I've had the experience myself too.
Can be a lot to take in but I'm sure it'll make sense.
I'll make a picture of my Grasshopper set up and try to give a good explanation.
Take might take a bit though... but in the meantime I think JR's post has a great summary of the basic info :

Jonny wrote:

If you haven't already got ball bearings in it, they are a useful mod (less wear, longer battery life, and a tiny bit more speed) - they are also an awful lot cheaper than they used to be - you need nine "1150" size and one "850" - a full set on eBay will be around

ok sorry fro being a bit thick here,so if i bought this...



what else do i need to buy, will it work with my transmitter and battery and 480 motor, or will i have to buy a 540 motor?

the spec of my motor is,
JAMARA LIPOWER 480HS
3 - 9v
22000 rpm max
5.8amp max draw.
it dosent say how many turns(?) it has

Message was modified to show the eBay item directly.
Hitting the eBay icon when posting and then placing the eBay ID number in between will embed the image on the forum :

Hi
The speed controller you have there is a MSC (Mechanical Speed Controller)
A ESC (Electronic Speed Controller) is a solid state (no moving mechanical parts) speed controlling unit.
BEC (Battery Eliminating Current) this refers to a regulated voltage supply for receivers fitted to ESC's only.
Your receiver can only handle maximum 6 volts.

ESC's comes with a build-in voltage regulator to reduce the 7.2 volts supplied by your 6 cell stick pack battery down to between 4.8 volts and 6 volts. ESC's come with a supply line via a switch and a small red plug that fits into the receiver.

Your MSC is fitted with a non-regulated power supply (the line with the small red plug)

If you want to remove the 4 dry cell batteries as a 6 volt power supply to your receiver you will have to fit in-line a switch and voltage regulator between your MSC and that small red plug going to your receiver.
I hope this helps,
Marius