10 Aralık 2007 Pazartesi

You have to see it to believe it

4 yorum:

koray dedi ki...

evet dunyanin ilk otonom kablosuz cihazi olarak bunu gosteriyorlar. icinde pil yok ve mis gibi kablosuz uzaktan kumanda. bu manada pillerini ayda bir yeniledigimiz cok fonksiyonlu uzaktan kumandalardan daha gelismi bir cihaz gozumde.

fevri dedi ki...

pil yok derken??

koray dedi ki...

evet o uzaktan kumanda cihazi pilsiz. bir tusa basinca cikan belirli frekanstaki sesle calisiyor.

fevri dedi ki...

guzel ismis yav
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In 1956 Robert Adler developed "Zenith Space Command", a wireless remote. It was mechanical and used ultrasound to change the channel and volume. When the user pushed a button on the remote control it clicked and struck a bar, hence the term "clicker". Each bar emitted a different frequency and circuits in the television detected this noise. The invention of the transistor made possible cheaper electronic remotes that contained a piezoelectric crystal that was fed by an oscillating electric current at a frequency near or above the upper threshold of human hearing, though still audible to dogs. The receiver contained a microphone attached to a circuit that was tuned to the same frequency. Some problems with this method were that the receiver could be triggered accidentally by naturally occurring noises, and some people, especially young women, could hear the piercing ultrasonic signals. There was even a noted incident in which a toy xylophone changed the channels on these types of TVs since some of the overtones from the xylophone matched the remote's ultrasonic frequency.