0 צפיות · 10/04/25
The blue LED was almost impossible to make
0
0
0 צפיות·
10/04/25
LED's don't get their colour from their plastic covers. The blue LED was supposed to be impossible—until a young engineer proposed a moon-shot idea.
להראות יותר
0 הערות
sort מיין לפי
0 צפיות · 10/04/25
