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utkarshjain
02-05-2010, 04:07 PM
hi guyz..
i have a remote control in which there are a total of 6 pins--
1. there is 1 pin for +5v(to this directly connected to battery's +7.4v)

2. there is 1 pin for ground(to this directly connected to battery)

3. there is pin no.1 which is operating as per the switch used(shown in figure)

4. there is pin no.2 which is operating as per the switch used(shown in figure)

5. there is pin no.3 which is operating as per the switch used(shown in figure)

6. there is pin no.4 which is operating as per the switch used(shown in figure)

when i press any button then nothng happens(after connecting supply)
all connections are ok and the battery is li-ion 7.4 v 2000 mah and 4 motors are dc geared 100rpm used...
the 1s and 0s in the fig. means +7.4v and 0 v respectively
infact when i pressed up button then instead of getting 1 0 0 1 i was getting 1111 (1 means here +7.4v so no motor could run)
the remote is from mitbots and it is seems a good pcb....i am posting the picture of that pcb also...

plz help immediately...my examz are starting soon and techfest are going to begin just after the examz

shobhitkukreti
02-06-2010, 06:20 PM
It is not a really convincing circuit diagram. Post the circuit diagram please

utkarshjain
02-06-2010, 11:30 PM
remote is shown in pic. and the cicuit diagram indicates following:
when a button (up/down/left/right) is pressed then following is obtained output from remote which i directly connect to motors...
1. up: 1 0 0 1
2.down: 0 1 1 0
3. left: 0 1 0 1
4. right: 1 0 1 0

here 1 indicate logic high (battery voltage)
here 0 indicate logic low (battery ground)
there are 6 wires going out from remote pcb
(i)+5v (to which i am supplying +7.4v from li-ion)
(ii)ground (connected directly to battery ground)
(iii) pin1 on which output comes as indicated in the sequences above shown for up,down,left,right
(iv)similarly to pin2 on which output comes as indicated in the sequences above shown for up,down,left,right
(v)similarly to pin3 on which output comes as indicated in the sequences above shown for up,down,left,right
(vi)similarly to pin4 on which output comes as indicated in the sequences above shown for up,down,left,right

one of the student in my branch told me that he also made the circuit like this and it worked fine...but in my case as i press a button the motor does'nt start..when i used multimeter i found that instead of getting +7.4v(logic '1' when i pressed up button) at all pins - pin1,pin2,pin3,pin4 i was getting +7.4v...i think that it may be due to back emf from motors...if it so then what shall i do..if any other reason plz do tell...i haven't used any l293d or l298 ic here ...circuit is as indicated in the previously posted figure...plz reply immediately

akshay66
02-08-2010, 09:42 PM
Whats the point of using such circuits??They are not reliable they can even stop working in the middle of your robo race.It is always advisable to a h bridge or driver.They actually easy your work.If you think emf is the problem use diodes.I still advice you to buy a proper remote with driver.The circuit is not clear so i can't comment please post it in a proper way & if possible link to remote(mit bots).

Regards Akshay,

vikas
02-08-2010, 09:48 PM
Come on man that thing will not win anything ... Those cheap motors are inefficient,heavy and eat battery.

Get some good stuff if you wanna win ... :) . Dont go for shortcuts.

akshay66
02-08-2010, 10:00 PM
Frankly Telling I would have used two toy motors here with gearboxes worth 80 both the motors.I am talking about those cheap tank toys & police toys with a single motor driving 2 wheels.They are fast, cheap, tyres are almost all terrain & no problem even if they broke after the event.

GOD MADE HEAVEN & EARTH,REST WAS MADE BY CHINESE!!

Regards Akshay,