The Laptop, Circa 1968 120
Harry writes "In 1968, computers tended to occupy entire rooms, and were therefore hard to take with you. But Computerworld reports on Anderson Jacobson's 75-pound Teletype-terminal-in-a-case, an early attempt to let folks compute from anywhere. (Well, anywhere they had power and access to a telephone for the Teletype's acoustic coupler.) Wheels were optional."
Re:How is this a laptop? (Score:3, Informative)
They don't really call it a laptop, they use 'laptop' to draw a comparison between the somewhat portable teletype and modern portable computers.
Re:Once upon a time (Score:2, Informative)
An ASR-33 is 110 baud.
Re:1976 TI Silent 700 Terminal - $1995, 13 lbs. (Score:5, Informative)
Um, yeah, that "progress" was called the microchip.
Yes, what I think a lot of people may have failed to realise with the ASR-33 is that it's all mechanical. The only electrical part is the solenoid that flips some pins sticking out of the shifter drum back and forwards.
When you press a key, the keypress is turned into a stream of data by a mechanical shifter. When you receive a character, the serial data is unshifted and printed by a mechanical shifter. No electronics to be found at all.
Re:1976 TI Silent 700 Terminal - $1995, 13 lbs. (Score:3, Informative)
Let's not go overboard. The modem is electronic. It is almost certainly also digital. It would just be discrete parts, such as the 7400 series invented in 1964 -- with no microprocessors or any other chip with more than a handful of gates.
Re:1976 TI Silent 700 Terminal - $1995, 13 lbs. (Score:3, Informative)
Let's not go overboard. The modem is electronic. It is almost certainly also digital.
Early FSK modems, below 1200 baud, were analog devices. The output side was just an oscillator switched between two frequencies, and the input side was a pair of filters. This was a version of the technology used for radioteletype (RTTY), where it had often been implemented with tubes. (There are some very retro radio hams still using all-tube demodulators with mechanical teletypes.)
At 1200 baud and above, modem technology changed drastically, and digital components appeared. But modems were still mostly analog devices until DSP-based modems became economically feasible in the 1980s.
It was called TTY Art (Score:3, Informative)
Re:The true first portable modern computer... (Score:3, Informative)
Re:1976 TI Silent 700 Terminal - $1995, 13 lbs. (Score:3, Informative)
Yes - the excact same mecahnism, actually: It was a current-loop - if current flowed it was a 0, if it stopped, it was a 1! (In some cases, it was +/- current, and in other cases it was 15mA for 1 and 4mA for 0. There were probably several other "standards" as well.)