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Remove the case from a ZX81 with a RAMpack and connect wireless
interfaces to the bits where the cable´s connected to the motherboard,
a transmitter to the video signal before it goes into the modulator,
cover it in Peltier devices to deal with overheating, then leave it
permanently plugged in
in a cupboard somewhere in a box. Take the
empty case, put a similar transmitter and receiver inside it, and use it
as if it´s the actual computer. Same goes for the cassette interface.
No more RAM wobble.
And it only took me twenty-seven years to
think of a solution.
[DrBob, Dec 19 2008]
||Congratulations. You just re-invented the dumb terminal!
||Rather dumber than before though, since it now does even
less, no? Actually, how dumb were they exactly? Did they
convert keypresses to ASCII and generate characters, or just
send and receive signals?
||They generated characters which appeared on the monitor in front of you before you pressed 'Send' to whisk your communication off to the mainframe. I really don't know at which end of the pipe the conversion was done but I would guess that it was at the terminal end rather than when it arrived at the computer.
||I thought Blu tack was the answer?
||Right, so not Xenu then?
Thanks, [DrBob], it must be i
suppose, but what about the likes of the VT52? Was it really
possible to do all that back then in one little box?
||You're going back a bit further than I do with the VT52. I started on ICL orange & brown boxes (which had satisfyingly chunky keyboards) in the early 80's.
||The first thing i used was some sort of teletype thingy with feet which reminded my seven-year old self of a robot. It was at the local college and communicated with some kind of Hewlett-Packard mainframe in London. I wasn't aware of the details. What i've never got is how video terminals used to work before microprocessors.
On looking at your link, i realise i actually meant the VT05, which could scroll and do direct cursor addressing, so presumably it had local storage, and since it predates eight-bit processors and the likes of the 2114, i don't get how it stored the display. If there's a piece of paper, the characters are on it and tend to stay there, but on a scrolling video display, that can't be so.
Come to think of it, you could also use a ZX81 as an interface to another ZX81 but replace the ROM with terminal-type software.