Kontrol Mute Volume Sentuh

Rangkaian kontrol mute volume ini sangat sederhana dengan hanya mengandalkan satu buah ic pintar NE555. Rangakain ini bisa digunakan untuk rangkaian Audio Amplifier anda atau rangkaian saklar lainnya sebagai On-Off suatu rangkaian....

Here is another simple circuit to mute the volume of Audio devices through simple touch. It exploits the action of the flip-flops in the timer IC 555 to reduce the volume of the Audio amplifier. IC NE555 is designed in the toggle mode. Its lower and upper comparator inputs are connected to the touch plates which can be membrane switches or two pieces of conducting plates. The inputs of comparators are stabilized through R1 and R2 to avoid floating.

Touch controlled Mute switch circuit

When the touch plate connected to pin 2 is touched momentarily, output of IC1 goes high and T1 conducts. The centre tap of the volume control is connected to the collector of T1. So when T1 conducts current going to the amplifier drains through T1. This reduces the volume.IC1 remains latched in this position with LED on. When the touch plate connected to pin 6 is touched momentarily, output of IC1 goes low and T1 turns off. This restores the volume.

Source:  www.extremecircuits.net

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Line Follower ROBOT Controlled by 2051

Kuskel Robot- This Robot use two motors control  rear wheels and the single front wheel is free. It has 4-infrared sensors on the bottom for detect black tracking tape, when the sensors detected black color, output of  comparator, LM324 is low logic and the other the output is high.

Microcontrollor AT89C2051 and H-Bridge driver L293D were used  to control direction and speed of motor.

Fig 1. Circuit diagram of my Robot.

Fig 2. Circuit diagram of Infrared sensors and comparators.

Fig 4. Position of sensors,  left hand side is side view and right hand side is top view.
Software
Software for write to AT89C2051 is robot1.hex ,which was written by C-language ,the  source code is robot1.ccompiled by using MC51 in TINY model with my start up code robot.asm .
MPEG files
Sample of competition between 2051 and 68HC11.

movie1.mpg (1,303kB)

movie2.mpg (373kB)

Source : www.kmitl.ac.th
Contact Owner : plermjai@loxinfo.co.th

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