15 Jul
2011
15 Jul
'11
8:04 p.m.
For all of its faults it was still the market leader.
Did you know you could plug a B&W TV camera into the back of a VT100 and see
the picture on the screen? I did it at Dec Park (Reading UK) one day and
drew a large crowd.
I can remember the tiny on/off switch and the vertical DB25 connector but that is all I recall about the back of a VT100. I guess
there must have been a BNC
connector? I do vaguely recall occasionally having to dissuade academic staff
There was of course also the mains input connector (IEC type, fuse and
votlage selector.A 3 contact jack socket (phone socket, like a hedphone
connector) for the keyboard. And 2 BNCs.
One was video output, and carried the composite video signal equivalent
to that shown on the built-in CRT. The frame rate was selectable as 50
ot 60Hz in the setup. The other was video input. This was just video (not
composite video and sync), you had to sync the extranl video source to
the sync signal appearing on the video output socket. This means
displaying live TV, etc was next-to-imposible.
from plugging their thinwire ethernet segment into the
back of their terminal but
I don't remember which type. I suppose it was probably the VT100.
MAybe a VT220, whcih ahd a (composite) video output BNC socket on the
back. No video input on that one, though. I remember when I was at
Bristol we had a thinwire segment go down. After checking for sillies, I
put a 'scope on it and found the unmistakable composite video signal.
Yes, sombody had plugged a spare T-piece into the back of a VT220.
Did the terminal automatically sense an external video connection or was it
necessary to manually disable the video generated internally? I guess it was
probably expecting 525 lines, 60Hz but could cope with 625 lines, 50Hz?
My VT220 has a BNC connector on the back but in this case it is an output. It
produces a nice picture on a monochrome 625 line 50Hz monitor after adjusting
the vertical hold.
I thought hte VT220 had a setup option for 50 or 60Hz vertical too. If
so, in the former setting, it should display fien on a 625 line monitor
without any adjustments.
-tony