Step 2: Getting started (Hardware phase)

Hardware phase
                              first of all open the remote of the Rc car. You will analyze that there are four switches. when we press the button each switch is closed.. Before pressing the button turn on the remote and check the voltage across the terminals of the switch  it should give a value.. after pressing the switch hold the button and check the voltage it should show zero..

this concludes that our remote is working on short circuit technique. that is if there is a voltage across the switch and when its pressed it is short circuited.

Observe that one wire is common in all the switches its the ground of the circuit. which concludes that we need to solder five wires in the remote. one for each switch and one for ground.

it can be checked that when u short the ground wire with any of the switch wire the car performs the action of the switch who's wire is shorted if all the four functions are performed then it means u have picked the right ground. and the right switch wires.

here are the pcb design and the simulation of the circuit for interfacing (download parallel port circutary)
<p>My rc car remote switch terminal closes with the positive terminal of the remote not by ground.... i cannot connect positive to emmitter of the transistor.....what can i do....help me with dis... plz </p>
<p>it might close with the positive terminal of the remote but the terminal that is joining must be a ground.. <br>In-fact it doesn't matter if it is on high voltage or low. because when the switch is pressed both go to same potential. <br>therefore all you need to do is find out which terminal of the switch is high and which is low. just connect the low one to the emitter and high one to the collector and you are good to go.</p>
<p>My rc car remote switch terminal closes with the positive terminal of the remote not by ground.... i cannot connect positive to emmitter of the transistor.....what can i do....help me with dis... plz </p>
<p>i want to make front wheel moving r.c car which makes it easy to turn...</p><p>wiil u have any idea or any source from where i cn learn abt it...??</p>
<p>I dont get what are u trying to say .... do u mean u want to make a fore wheel drive? </p><p>the above car is rear wheel drive and with turning functionality.</p>
<p>Buddy!! Can't I use this for a RC Infrared Helicopter!! i'm slightly confused because of the remote has VRs Not switchers!! :)</p>
exacly u have the answer in ur question . from a parallel port u can only get 8 bit information so u can enable/disable 8 switches but when it comes to VRs then u need either more pins or serial port. therefore u cant do it. first i had the same project in mind but i faced the same problem. <br><br>Regards<br>Umer Javaid<br>NUST <br>Pakistan
please send me the program code to <br>mohammedeissa10@yahoo.com <br>e.mohammedeissa11@hotmail.com <br>
Also what u did is great job
Thank u :) <br>the code is available here in last step after videos there is &quot;rc project.zip&quot; (5MB) button click and download the complete source of the project :) enjoy <br> <br>Rate if u like it . Thanks
Hello I know this might sound like a stupid question but is the transistor necessary?Why? <br>Cause it might work even without it(just a thought but i'm not sure about it) <br>And Do I still need to use batteries on the remote control?
Normally when u press the button with your finger u connect two metal pates an when the are joined the voltage difference between them gets zero as a result a signal is emitted from the remote and the car reacts accordingly .. now the purpose of the transistor is to make a contact between those metal plates but using electric signal from parallelport (no physical force required) so to do that transistor is necessary as it i the device that gets short between emitter and collector when base is at a certain voltage ...therefore we can make those metal plates connected even though no one has pressed the button physically ... <br>and yes u need the batteries in the remote as u have just pressed the button using the circuit if there is no battery then there is no use of pressing the button :) hope u have find your answer .u can ask if any further help is required ....... like,comment,rate :)
It's funny how you put Opel and Honda stickers on a Toyota RC car
thought no one will ever notice :D
I did. Why did you
was modifing it .. did all the paint and led's .. then i only had these stickers so i put them too.. <br>
excuse me . i need help . i make a project of rc car control by parallel port . my complete circuit work very well but when i conect my collector wire with parallel port my car start working. what should i do. some one tell me when u connect your car with paralllel port your car command control by port . but i want control it by turbo c program. but when i compile my turbo c code it not work. can u tell me what is fault in my project. because tomorrow is last day of submit project plzzz. reply and i want told u i have window 7 in my laptop . &quot;&quot; that is y my turbo c cant control my car&quot;&quot;????
first of all how do u know your circuit works fine.. because u dont connect the collector to the parallel port .. its the base that is to be connected instead. and the code doesnt work with windows 7 .. actually i used windows 7 too and then it didnt work then i replaced it by windows xp and same program worked awesome..
i have different remote there is one switch inside how i can work in this remote i means how to connect four wire in one switch <br> <br>this is my remote from behind <br>http://im20.gulfup.com/VQJ41.jpg[^] <br> <br>http://im14.gulfup.com/Y6wh2.jpg[^] <br> <br> <br>also i have another remote i think there are four switch but i'm not sure <br>if this remote 4 button can you explain how to connect 4 wires <br>http://im28.gulfup.com/jLRV2.jpg[^] <br> <br>remote from behind <br>http://im20.gulfup.com/XkL32.jpg[^] <br> <br>
First of all the thing is if your RC car moves forward backward left and right then it surely means there are 4 switches because one switch can only control one movement so the point that there is only one switch its wrong take a better look on your remote again .. i think u are confusing it with the on off switch as i see in the image u attached .. now the two &quot;S&quot; shaped structures are your ground u can check that by attaching a Multimeter black wire with the battery's negative end and the red wire with the S shaped metallic structure if the multimeter reads zero it means i am right and the &quot;s&quot; is ground. Now there are metallic thin naked wires under each end of the &quot;s&quot; as marked by green arrows in the picture. all u have to do is attach the s with the ground of the circuit (BJT's one) and the naked wires (marked with green arrows) with other pins so your circuit will work nice and fine .. if u are still confused or in a doubt tell me , i will try simplifying the things .(your other remote image wasn't clear but it will also work fine if u figure out the right wires)
I am still confused about &quot;S&quot; At any point it must be connect the wire from the back ?
the s is matellic u can even connect the wire from the front too but soldering from the back will make it more hard and less likely to break
its clear now <br>thank you (: <br>
see other remote <br>http://store3.up-00.com/Nov12/0eb16506.jpg <br> <br>http://store3.up-00.com/Nov12/yfW16506.jpg
here is the edited image .&quot;s&quot; is marked red and the naked wires are marked green
Nice to see a project that does not use an arduino. There are a boat load of old pc motherboards around that can be adapted easily for this type of project. Also goes for recycling old equipment. I have done several instructables on this sort of thing and wish people would do more. I intend to do a mod on a 486 laptop to do the same thing, but boot with a freedos floppy and use a compiled freebasic program. Have not made time to do it yet.
thanks for visiting and if u have any problem u can ask
Thanx for the offer, but I can probably handle it.<br>
Dude, I can't find the transistor at a local electronics parts shop in Islamabad. They tell me MPSA06 is American part number and they have Japanese/Chinese parts. They say the part number has to be 2N-something or like 7806C or 7906C. I'll check College Road after a few days; but, meanwhile, I am trying to find an equivalent of the transistor you used. Any help would be welcomed.
dear<br>u can find it on college road at &quot;IC Master&quot; u can use any transistor that is feasible for switching purpose or even u can use a generic transistor .....<br><br>still if u r confused try <br>www.alltransistor.com<br>or try this <br>http://alltransistors.com/crsearch.php?mat=Si&amp;struct=npn&amp;pc=0.625&amp;ucb=80V&amp;uce=80V&amp;ueb=4V&amp;ic=0.5&amp;tj=150%C2%B0C&amp;ft=100MHz&amp;cc=-&amp;hfe=50MIN&amp;mnf=&amp;caps= <br>for equivalent transistor or use C828 ...... <br><br>thanks for ur comment ..... <br>u can still ask if somethink is nt clear
Hey Nice Project really easy to do. <br>But what if i wanna do this with usb and not serial port ??
yup u can but u have to change the coding likely .....<br>its more convenient that u use a usb to parallel port converter it will b easy else the whole code will b changed <br>
Alrite m gonna give it a try. <br>Thanks for help!!!
no problm <br>actually in parallel port one can handle each bit saperatly while usb i think transmits searially <br>

About This Instructable


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Bio: hi, m Umer from Rawalpindi Pakistan. i m doing Computer Engineering form NUST(EME campus). though m doing Computer Engineering but My Interest is in ... More »
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