Nostalgic Memories of 555 Timer IC!

 This the 555 timer Integrated Circuit with which we used to make Code Practice Oscillators when we were short wave listeners to practise Morse Code while preparing for the Amateur License Examination. In those early days of integrated circuits, it was mind boggling to think that this tiny device incorporated the equivalent of 25 transistors, 2 diodes and 15 resistors! Remember that we were just coming out of the bulky vacuum tube era.


73 de Jon, VU2JO

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