Miniaturized electronic tubes Distribution: world
Tokenring vs Ethernet 10 years later 3741
Charles Mills re: years later microchannel 16mbit t-r card were going for something like $900-card aggregate 16mbit t-r LAN had lower aggregate network thruput than...
Miniaturized electronic tubes 3739
The story I heard was that some of that was a deliberate choice to reduce the plane's vulnerability to EMP. (Or maybe that was just a fortunate side effect.) Vacuum tubes are amazingly...
Until how much they could have miniaturized the valves, thinking to printed circults with directly soldered miniaturized valves, in which the breakdown of a valve involves the subsbreastution of the entire module?
We had circuit boards like that when I was in the USN. In 1968 plus 1 I reported aboard ship. There were some stepping solenoid operated distribution boxes. They let a rader operator select which rader he could view on the PPI, radar scope. He turned a dial on the scope panel, and it turned a stepping solenoid. Which operated the solenoid in the radar room. And it then showed him the radar images he wanted to look at. Inside those boxes, about 6 feet high x 3 feet deep and 3 feet wide, were a number of electrical curcuits.
And a large number of small printed curcuit boards, with miniature valves-vacuum tubes on them. The wires from the base of the tubes-valves were soldered to various places on the circuit board.
When we had to repair one, we shut off the power to the distribution box, pulled the circuit card, put another circuit card in its place, then took the card over to the repair bench. Replaced the valves-tubes. So we did subsbreastute the entire module. We had to repair them, they were expensive and shipping time was critical. So we couldn't ship them off for repair unless the board went completely bad. There was some kind of replacement program that if we had 5 cards go bad such that we couldn't repair them, in order to get 5 replacement cards we had to turn in to the supply office the 5 bad cards. The cards were about 6 inches long and about 2-3 inches wide. They plugged into the distribution box just like a computer card into a slot in the computer.