YouTube videos of vintage PDP-11/40, ASR-33, VT05, etc
bfranchuk at jetnet.ab.ca
Sun Jan 20 16:21:44 CST 2008
Tony Duell wrote:
> And while not a terminal, and while not triggeered by ^G, the HP9830 has
> an electronic beeper used to signal errors. It's simply triggered by a
> single line from the I/O interface PCB and things like the frequency and
> dureation are set by r's and C's on the PCB, they're not software
> controlled. But it shows the sort of design that when into these old HPs
> when you realase there's a little circuit -- OK, just a couple of gates,
> a trnasisotr, and a few passives -- to geenrate an amplitude envelope on
> this beep to make it sound more pleasant. One machine where every cent
> was _not_ saved...
I like a real bell.
PS. stupid HTML email ... you can't enter a CTL G. :(
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