Today in 1955, AT&T Bell Laboratories announced the completion of the first fully transistorized computer, TRADIC (transistorized airborne digital computer).
Bell Labs’ engineer Jean Howard Felker started in 1951 to develop TRADIC for the United States Air Force. M. M. Irvine in "Early Digital Computers at Bell Telephone Laboratories," IEEE Annals of the History of Computing:
Other engineers within Bell Labs also obtained sample transistors and experimented to determine what could be accomplished with this new, exciting device. Jean H. Felker… received a new point-contact transistor that had been fabricated by Bell Labs’ transistor development group. He first tried to build a linear amplifier with it but could not prevent it from oscillating. Finally, he decided that if he couldn’t prevent it from oscillating, he would see if he could use it in that mode.
Felker then built a blocking oscillator that, when triggered, caused a simple pulse to occur. On examining the pulse output, he observed that it was very fast (for that time), rising and falling in a few hundredths of a microsecond and requiring a very small amount of power.
Bell Labs’ lore relates that Felker then became notorious for roaming the halls and various offices, showing people the device and asking if they could possibly use it in their work. Unlike the usual development scenarios, he had a solution and was looking for a problem. The end result of his search was the birth of TRADIC (transistorized airborne digital computer) when he realized that his circuit could
serve as a regenerative amplifier as part of a high-speed clocked circuit in a fast, lightweight, solid-state digital computer using low power.