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 Do you know what the worlds deadliest animal is ?

دائرة مرحاض تلقائي بدون لمس " An Automatic Flushing Toilet For Your Home "

 مراحيض تعمل تلقائيا بدون لمس لمنع انتقال الأمراض ..
يمكن استخدام الدائرة التالية لوضع تصميم مقارب يقوم بتشغيل ذراع ميكانيكي عند وضع اليد بين ثنائي الاشعة تحت الحمراء D2 وبين الترانزيستور الضوئي ..

الدائرة الالكترونية :
 

Wireless On-Off Switch Circuit diagram 

مكونات الدائرة الالكترونية :
R1 = 470R
R2 = 100K
R3 = 3.3K
R4 = 10K
D1 = 1N4007
D2 = IR LED
Q1 = L14F1
RL = 5Vdc Relay
IC = CA3140
Q2 = BC548

Normally home appliances are controlled by means of switches, sensors, etc. However, physical contact with switches may be dangerous if there is any shorting. The circuit described here requires no physical contact for operating the appliance. You just need to move your hand between the infrared LED (D2) and the phototransistor (Q1). 

The infrared rays transmitted by D2 is detected by the phototransistor to activate the hidden lock, flush system, hand dryer or else. This circuit is very stable and sensitive compared to other AC appliance control circuits. It is simple, compact and cheap. Current consumption is low in milliamperes. The circuit is built around an IC CA3140, D2, phototransistor and other discrete components.

Circuit Operation:

When regulated 5V is connected to the circuit, D2 emits infrared rays, which are received by phototransistor Q1 if it is properly aligned. The collector of Q1 is connected to non-inverting pin 3 of IC1. Inverting pin 2 of IC1 is connected to voltage-divider preset R4. Using preset R4 you can vary the reference voltage at pin 2, which also affects sensitivity of the phototransistor. Op-amp IC1 amplifies the signal received from the phototransistor. Resistor R3 controls the base current of transistor BC548 (Q2). The high output of IC1 at pin 6 drives transistor Q2 to energies relay RL1 and switch on the appliance, say, hand dryer, through the relay contacts.

The working of the circuit is simple. In order to switch on the appliance, you simply interrupt the infrared rays falling on the phototransistor through your hand. During the interruption, the appliance remains on through the relay. When you remove your hand from the infrared beam, the appliance turns off through the relay. Assemble the circuit on any general-purpose PCB. Identify the resistors through colour coding or using the multimeter. Check the polarity and pin configuration of the IC and mount it using base. After soldering the circuit, connect +5V supply to the circuit.

دائرة تشويش على رموت التلفزيون " TV Remote Jammer "

دائرة تشويش على رموت التلفزيون باستخدام المتكاملة 555

 TV Remote Jammer circuit

مكونات دائرة التشويش

Components	Rating	Quantity
IC	NE555	1
Transistor	BC557	1
Resistors	1K	1
	560	1
	180	1
POT	10K	1
Capacitor	0.01uF	2
Battery	9V	1

فيديو المشروع

حقائق حول استخدام الانترنت

Internet Users Send 204 Million Emails Per Minute

هل تصدق أن سرعة المربعات هي واحدة وحركتهم متساوية

Believe it or not, these four squares move at the same constant speed

These four squares appear to move at different speeds, stopping and moving, waiting for each other in pairs. In reality, they are always moving at exactly the same constant speed. Seriously. I opened the GIF in Photoshop and used guides to measure it—in every frame, the squares align perfectly.

Their motion is exactly the same but the stark contrast of the lines and the light yellow and the dark blue makes them look desynchronized while in motion. Your brain has difficulty seeing the yellow edges against the white and the dark blue against the black.

The yellow appears to speed slow down as it enters the white lines, while the blue appears to slow down as it enters the black lines. In reality, it's all an optical illusion. Only when the squares get close to each other your brain realizes they are moving at the same speed.

علم الميكانيكا

Magic

فن تصوير تفتح الزهور في الصباح

This time lapse of fireflies is art in motion

Shot over the Summer of 2013 primarily in Lake of the Ozarks, MO as well as Grand Ledge, MI. The majority of the Summer I dedicated to photographing fireflies, because, well, they are just awesome. Nothing quite ends a hot and humid Summer day like the blessing of the majestic fireflies. Lake of the Ozarks is a fantastic home to the creatures. Being out on the boat and watching as they light the treeline with their all night disco party is just amazing. My good friend Brandon McCoy was nice enough to compose this track specifically for this video, which he tore-up, fantastic work on his part. This is my first complete time-lapse video, more to come!