The $40 Robot

[sohailsameja]

I managed to complete the circuit
1)on white surface voltage at bases is between 0.705v to 0.865(red light is of or slightly glowing)
2)on black surface it is generally between 2-4Volts(it is slightly glowing

I have NOT yet tried motors on it as I have found none which is geared)it is 2 days to competition)
Could you predict the outcome

Note: there is limited space to solder the motor wires i might short it.is there another way or shall i brave on?
Here are some pics
*coming soon(5 min)

[waltr]

Ok, you are getting there.
The sensors output Voltages sound close. Have you adjusted the Pots yet?

Before connecting the motor you can measure the Voltage out of the L298 with a Voltmeter to tell if the motor driver is 'turning on' the motors. It is a good idea to test this before connecting the motors.

Instead of soldering the motor wires directly to the L289, solder short wires (the same size you used to wire the logic) to the L289 out to near the edge of the perf board. Then run the stripped wire ends through two hole in the perf board to create a 'terminal' onto which you can solder the motor wires.

I have been following your questions and progress but only reply if I have real advice.

[sohailsameja]

well thanks a lot yes i adjusted the pots on white and black surface.when measuring the voltage at the l293d sholul i ground one lead and test with the other or how should i do it.actually the l293d is mounted on the dip socket so cold i insert a very thin wire inside the dip from the top and then solder the motor wire to the thin wire?
IN the L293D are the motor wires supposed to be connected in a specific way or just any polarity to any pin on their respective side
The battery is 9V could i use a 12 dc motor whichis not so big (ungeared) so that speed is minimal hence it goes slow?