On Nov 3, 21:23, D. Peschel wrote:
>
> US UK
>
> NTSC -- smooth and flaky PAL -- flickery but more reliable
60Hz vertical scan - smooth 50Hz vertical scan - more flickery
NTSC - flaky PAL - more reliable
> VHF frequency bands: VHF frequency bands:
> channels 2-13 ?
> (1 was scrapped in short order)
2-13 (or was it 2-12?)
TV was removed from the VHF band in Europe some years ago. The frequencies
have been reallocated for various comms uses.
> UHF frequency bands: UHF frequency bands:
> channels 14-99? ?
> (not sure -- little-used, many
> conflicting terms and marketing)
15-65 IIRC
> Satellite and cable TV bands: Satellite and cable TV bands:
> Too complicated for me to guess ?
Mostly C-band? Ku-band
> "tuning in" may be required to relate ideal
> channel number with actual band number
> (which changes from area to area)
although they are published in various
places
> Devices attached to ch. 3 or 4 Devices attached to ch. 36?
> (whichever is unused) in past
Ch.36 is actually allocated to other uses, so when the "Channel 5" TV
station went live, mainly using channels around ch.36, lots of people had
problems :-) Most of the TV stations use channels separated by 3 chanels
(so 33, 36, 39) to minimise interference effects.
> To keep this on the topic of the thread, I *am* interested in getting a
BBC.
> I guess I'd need a PAL monitor and a 220-volt, 50-hz power supply to run
it
> though. Does anyone have any ideas?
There was a U.S. version with a 110VAC PSU. The standard PSU is a
switcher, though, and I know of one person who (inadvertantly) used it
successfully on 120V. I got a phone call one day (in my capacity as
engineering support person at an Acorn distributor) from a guy who'd bought
a BBC and a monitor. He was having trouble with the monitor; it turned out
he was working in Saudi Arabia, and had been using a TV originally. All
was well, until he upgraded to a monitor bought in the UK. It turned out
the monitor was intended for 240V, and didn't like Saudi electricity. Then
it dawned on us -- the Beeb was OK, even though it was also running on the
same Saudi 120V. YMMV :-)
I think the 50/60Hz difference *may* be a problem, since a US monitor will
prefer to sync to 60Hz. The US BBCs had a modified MOS ROM, with US scan
rates and "colour" changed to "color" in the messages and BASIC keywords.
That was about the only difference, AFAIR. The line frequency won't
bother the Beeb PSU, but the monitor may not like the scan rate. It's very
similar to a CGA-style monitor, BTW. An Amiga colour monitor should work
well (Philips CM8833 or equivalent).
--
Pete Peter Turnbull
Dept. of Computer Science
University of York
Received on Wed Nov 04 1998 - 02:43:15 GMT