Restoring an RC Car

sinner · 2nd May 2009, 17:47

Hey Guys

I have this Huge RC car, which was gifted to me by a family friend, who apparently doesn’t know much about Cars, Toys, or Boys Toys related to Cars.

The problem is that this is a cheap Chinese RC car, so you can understand the quality issue of the electronics; however the body seems to be pretty decent.

The problem with this RC is that … It just doesn’t work , I mean even after the full charge of the Battery and the Remote , the car just won’t go more than a few inches.

I like the sentiments behind the gift, which is why I don’t want to get rid of it. But what good is such a big RC car if it can’t run, Isn’t it ?
So here am I, wondering and thinking to do some DIY stuff and rebuild this RC car.

What I have In mind.

First and foremost , I would like the change the Radio of this car. I mean to make it work.
Once that’s done I would want to know how can I make it faster.
And lastly … Cosmetic changes. ( Spray cans and tapes are ready)

Now I know we have a lot of techy guys here in TBHP , so calling all of you for help with the following questions.

What are the different types of RC motors.
Where can I find an decent RC motor in India.
Any idea how much it would cost.
Anybody who have done this kind of stuff ?

Some pictures of the said RC is attached.

Rehaan · 2nd May 2009, 20:26

Quote:

Originally Posted by sinner

....The problem with this RC is that … It just doesn’t work , I mean even after the full charge of the Battery and the Remote , the car just won’t go more than a few inches....

Are you saying the battery just runs out ? Or is there some other reason it dies?

There are endless (and expensive) mods you can do to an electric RC car, but i'm not sure this would be the ideal platform to do it on!

Right now we dont know anything about your car, besides the fact that it has a huge intercooler.

Put up some pics of the batteries it uses, the radio, and ideally - open up the car and put up some pics.

Chances are this is a fairly not-high-end RC car, and you should first focus on just getting it to work - rather than modifying it...imo.

cya
R

sinner · 2nd May 2009, 23:17

As per my not so technical knowledge , once the car goes more then a few inches , it kind of feels as if its gone out of range of the remote. Then you move a step closer to the car, it goes a little ahead and then stops, I hope you get the picture.

My initial wish is to just get it going first, and then will look forwards to any kind of mods.

I just popped the hood

some time back and did take a couple of pictures. Will be uploading in sometime.

I know its not a very high end RC, but to make it better we can at least use some of the stuffs, Like steering mechanism, wheels , and i don’t know may even the body.

NetfreakBombay · 2nd May 2009, 23:27

I have 4 - 5 such cards, all junked by my kid. These are Chinese no-name toys. Each one costs around 800 - 1000 Rs.

There are 2 - 3 RF bands which are used in remotes of these cars.

There would usually be a sticker in underbody and on remote that will have Frequency like 27MHz.

Smaller cars that cost 200 - 300 have same radio (but smaller motor / and weaker body).

Easiest solution might be to buy such a car for 300 Rs and sacrifice it get a working Radio.

sinner · 3rd May 2009, 12:04

So as i said i did open the car to see whats inside, appart from the huge intercooler.

and this is what i found

1st picture
As you can see there are a little too many wired for my confert. So i'm willing to loose the Head and Tail Lights of the car. ( Willing to make it non street legal)

But is you see the rear end of the chasis, there is a certain liquid discharge. could it be from the motor at the end

2nd Picture
Just a close up - which shoews the chinky made battery

3rd
Just a close up - Of the rear of the circuit

4th
The main board. now are those black boxes the Radio ? Also a wierd thing i noticed. the sticker on the board said 40MHz and the sticker on the remote says 27MHz. This is not normal isn't it.

Up to you guys now.

dinar · 3rd May 2009, 22:32

Quote:

Originally Posted by sinner

4th
The main board. now are those black boxes the Radio ? Also a wierd thing i noticed. the sticker on the board said 40MHz and the sticker on the remote says 27MHz. This is not normal isn't it.

Up to you guys now.

The black boxes are SSRs [solid sate relays] since the battery is a lead acid [10V ,700mA] battery these are used for controlling the drive motors. Only two of them are getting used, one to control the drive motor and the other to control the steering motor.
The 40Mhz sicker is for the chip on which it is stuck. probably a micro controller. To decode the transmitted PWM signal.
The problem will be with you transmitter and not the car electronics. From what you mention.

sinner · 4th May 2009, 13:24

INteresting piect of information dinar. So you suggest i should see if the Remote needs to be fixed ?

The remote has only two function, 1 to accelerate and reverse / brake , and 2 to steer.

As i mentioned the remote has a sticker thats says 27MHz, now when the frequencies won't match this could be the problem. But is it that any other 40MHz remote would work with this one.

I have another working RC ( A ferrari Enzo, got it with Top Gear subscription) should i try using its remote.

NetfreakBombay · 4th May 2009, 13:30

Quote:

Originally Posted by sinner

As i mentioned the remote has a sticker thats says 27MHz, now when the frequencies won't match this could be the problem. But is it that any other 40MHz remote would work with this one.

Take this car to any toy shop that sells cheap toys. Most of them sell toys that are manufactured in bombay itself or Chinese imports. Practically every local station on Western line has a few shops in market close to station.

There you can try a few remotes. I am sure you will find one that works with this model. Since remote is with smaller cars that cost 200/300 Rs, that might be easy way out. That is to buy a smaller car with a working remote that is compatible with this car.

And it would be fun to control two cars at the same time

sinner · 4th May 2009, 13:38

Quote:

Originally Posted by NetfreakBombay

And it would be fun to control two cars at the same time

Yes it will be fun Indeed. Will try doing that. BUt first i need to find a shop guys who's willing to do such experiment.

Sinner

NetfreakBombay · 4th May 2009, 14:18

For them its going to be a sale... so it should be enough incentive for them to let you try the remote with existing car.

dinar · 4th May 2009, 14:42

Since you mentioned the problem of not having range, I suspect the remote to be the issue here, It's simple your pocket radio can tune the same station as your radio in the car or at home, the range of a radio system depends more on the transmitter power than the receiver. Check if the batteries in the remote are providing full power or they do not charge properly [usually the culprit], batteries have to provide a certain minimum voltage for the circuit to work properly. May be the batteries are bad.
Again the 40Mhz is the speed at which the IC will work, the RF section determine the radio frequency [your 27Mhz] the black chip may be the one that decode the signal to the car, it like different instrucions sent to the car using 27mhz, the system has to understand the instruction [like go forward or trun,etc] that is done by the black chip and that has a speed 40Mhz , to do calcualtions for the instruction. Not the frequency of transmitter.
If you have anothe car with 27Mhz remote try using that [usually the black chip is programed differently so the car may react differently to different remotes].Get the same company remote [very difficult since the product is chinese]

Rehaan · 5th May 2009, 14:53

Quote:

Originally Posted by sinner

As per my not so technical knowledge , once the car goes more then a few inches , it kind of feels as if its gone out of range of the remote. Then you move a step closer to the car, it goes a little ahead and then stops, I hope you get the picture. ....

Aha.

In addition to what dinar has said, here is one more possibility.

It is quite possible that the wire connecting the antena to the PCB on either the car or the remote has been pulled off or broken. This usually happens when opening the car/remote - since it splits apart, but there is always that lone wire travelling from the PCB half to the other half (which houses the antena).

When this happens, the range can get severely affected - which is the problem you describe. Check it out.

cya
R

2nd May 2009, 17:47	#1
sinner BHPian Join Date: Feb 2005 Location: Thane - Mumbai Posts: 433 Thanked: 77 Times View My Garage	Restoring an RC Car Hey Guys I have this Huge RC car, which was gifted to me by a family friend, who apparently doesn’t know much about Cars, Toys, or Boys Toys related to Cars. The problem is that this is a cheap Chinese RC car, so you can understand the quality issue of the electronics; however the body seems to be pretty decent. The problem with this RC is that … It just doesn’t work , I mean even after the full charge of the Battery and the Remote , the car just won’t go more than a few inches. I like the sentiments behind the gift, which is why I don’t want to get rid of it. But what good is such a big RC car if it can’t run, Isn’t it ? So here am I, wondering and thinking to do some DIY stuff and rebuild this RC car. What I have In mind. First and foremost , I would like the change the Radio of this car. I mean to make it work. Once that’s done I would want to know how can I make it faster. And lastly … Cosmetic changes. ( Spray cans and tapes are ready) Now I know we have a lot of techy guys here in TBHP , so calling all of you for help with the following questions. What are the different types of RC motors. Where can I find an decent RC motor in India. Any idea how much it would cost. Anybody who have done this kind of stuff ? Some pictures of the said RC is attached. Attached Thumbnails
	() Thanks

2nd May 2009, 23:17	#3
sinner BHPian Join Date: Feb 2005 Location: Thane - Mumbai Posts: 433 Thanked: 77 Times View My Garage	As per my not so technical knowledge , once the car goes more then a few inches , it kind of feels as if its gone out of range of the remote. Then you move a step closer to the car, it goes a little ahead and then stops, I hope you get the picture. My initial wish is to just get it going first, and then will look forwards to any kind of mods. I just popped the hood some time back and did take a couple of pictures. Will be uploading in sometime. I know its not a very high end RC, but to make it better we can at least use some of the stuffs, Like steering mechanism, wheels , and i don’t know may even the body.
	() Thanks

2nd May 2009, 23:27	#4
NetfreakBombay Senior - BHPian Join Date: Jan 2008 Location: Bombay Posts: 1,481 Thanked: 1,128 Times	I have 4 - 5 such cards, all junked by my kid. These are Chinese no-name toys. Each one costs around 800 - 1000 Rs. There are 2 - 3 RF bands which are used in remotes of these cars. There would usually be a sticker in underbody and on remote that will have Frequency like 27MHz. Smaller cars that cost 200 - 300 have same radio (but smaller motor / and weaker body). Easiest solution might be to buy such a car for 300 Rs and sacrifice it get a working Radio.
	() Thanks

3rd May 2009, 12:04	#5
sinner BHPian Join Date: Feb 2005 Location: Thane - Mumbai Posts: 433 Thanked: 77 Times View My Garage	So as i said i did open the car to see whats inside, appart from the huge intercooler. and this is what i found 1st picture As you can see there are a little too many wired for my confert. So i'm willing to loose the Head and Tail Lights of the car. ( Willing to make it non street legal) But is you see the rear end of the chasis, there is a certain liquid discharge. could it be from the motor at the end 2nd Picture Just a close up - which shoews the chinky made battery 3rd Just a close up - Of the rear of the circuit 4th The main board. now are those black boxes the Radio ? Also a wierd thing i noticed. the sticker on the board said 40MHz and the sticker on the remote says 27MHz. This is not normal isn't it. Up to you guys now. Attached Thumbnails
	() Thanks

4th May 2009, 13:24	#7
sinner BHPian Join Date: Feb 2005 Location: Thane - Mumbai Posts: 433 Thanked: 77 Times View My Garage	INteresting piect of information dinar. So you suggest i should see if the Remote needs to be fixed ? The remote has only two function, 1 to accelerate and reverse / brake , and 2 to steer. As i mentioned the remote has a sticker thats says 27MHz, now when the frequencies won't match this could be the problem. But is it that any other 40MHz remote would work with this one. I have another working RC ( A ferrari Enzo, got it with Top Gear subscription) should i try using its remote.
	() Thanks

4th May 2009, 14:18	#10
NetfreakBombay Senior - BHPian Join Date: Jan 2008 Location: Bombay Posts: 1,481 Thanked: 1,128 Times	For them its going to be a sale... so it should be enough incentive for them to let you try the remote with existing car.
	() Thanks

4th May 2009, 14:42	#11
dinar Senior - BHPian Join Date: Mar 2006 Location: goa Posts: 1,066 Thanked: 57 Times	Since you mentioned the problem of not having range, I suspect the remote to be the issue here, It's simple your pocket radio can tune the same station as your radio in the car or at home, the range of a radio system depends more on the transmitter power than the receiver. Check if the batteries in the remote are providing full power or they do not charge properly [usually the culprit], batteries have to provide a certain minimum voltage for the circuit to work properly. May be the batteries are bad. Again the 40Mhz is the speed at which the IC will work, the RF section determine the radio frequency [your 27Mhz] the black chip may be the one that decode the signal to the car, it like different instrucions sent to the car using 27mhz, the system has to understand the instruction [like go forward or trun,etc] that is done by the black chip and that has a speed 40Mhz , to do calcualtions for the instruction. Not the frequency of transmitter. If you have anothe car with 27Mhz remote try using that [usually the black chip is programed differently so the car may react differently to different remotes].Get the same company remote [very difficult since the product is chinese]
	() Thanks