Monitor cable

"J. P. Gilliver (John)" wrote in
:

(I think he said the monitor he bought is HP.)


He did. I mentioned ELO as my known example. Comparing specifics is the only
way to go when firms break with convention.

Although a cheaper monitor likely aims to use a standard extension (m-f) for
its chassis connector rather than leave the supplier having to make a m-m
link themselves. The fact that you found more m-m links may be because this
fact drove Chinese firms to make them for interoperability. (Most times I
ever want ANY kind of adapter, it's usually the Chinese who had the sense to
make it ). I suspect there may be a lot of monitors like his, salvaged
usefully but lacking their original cables....

"J. P. Gilliver (John)" wrote in
:

voltage, and because it's often used in industry, running in ducts with
other cables with varied voltages and current in them. (Which is
incidentally why USB will never kill the serial port! In industry, USB
is probably considered an office toy for use in small, protected rooms.
If speed is needed, twisted

USB has a pretty short maximum length, too. (You can get extenders, but
they have electronics in them.)


Yep, and a low voltage tolerance and noise immunity, I imagine. A pretty
sorry standard to be named 'universal'. FireWire is far better, if the
fittings had been royalty-free it might have dominated.

"J. P. Gilliver (John)" wrote in
:

(I have just such experience - we used a BBC model B as a dumb terminal
to a VAX, lead running the entire length of a long building. After an
electrical storm, we had to replace something in the Beeb. Only happened
once.)


People built to last. Once... Hopefully the current economic crisis will
teach people to quit thinking of hardware as 'disposable'.

(And again, this is why we need low level VM's, it means we won't have to
change expensive hardware anything like as often as now. People should be
demanding this of computer firms, as a price of continued business.
Fortunately, for firms who want to let employees use their own systems at
work, that's exactly what they WILL end up demanding of anyone fulfilling a
big hardware contract. If it's the choice between spend, or not to spend,
that's about the only creative way out.)

"J. P. Gilliver (John)" wrote in
:

worrying about a wrong way. Signal electronics should survive a short-
circuit, the driving devices are usually chosen for it, most op-amps can
cope with this. They may use a low value output resistor to limit
current, too.

Indeed, though I'd not like to rely on it.


So long as we have a good common ground, those screw-retainers on D
connectors are bulletproof protection. This is another beef I have with USB.
Not exactly secure..

"J. P. Gilliver (John)" wrote in
:

cable might drop you down to 1024x768 for example, due
to the fall off in high frequency response (you can try a
high setting, like 1920x1080, but then it would look fuzzy).

50 feet of all but the most expensive cable will drop you well below
that (-:! It's more "ringing" - you get echoes, especially on vertical
lines - than fuzzy, though not that different.


Big fat cables with ferrite beads on each end. If over 25 feet, add a ferrite
bead clamped round the middle. The fat cables individually screen the analog
lines. I tried using a thin one once. Even a 6 foot length of that will be
worse than 50 feet of the good stuff.

I'm not sure if echo images will be worse with vertical cables, but one thing
worth trying is a short (1 to 3 foot) extension lead at the end of a long
one. It may be better with, or without it, the idea is to pick the length
that is less causing of standing wave reflections. (Similar logic to loading
coils to correct for various lengths of SW antennas).

In message ,
Lostgallifreyan writes:
"J. P. Gilliver (John)" wrote in
:

worrying about a wrong way. Signal electronics should survive a short-
circuit, the driving devices are usually chosen for it, most op-amps can
cope with this. They may use a low value output resistor to limit
current, too.

Indeed, though I'd not like to rely on it.


So long as we have a good common ground, those screw-retainers on D
connectors are bulletproof protection. This is another beef I have with USB.
Not exactly secure..

I agree, USB feels insecure. But I _hate_ those screws on D-types:
they're always coming off on the connector, and are the devil to do up
when you've got lots of plugs together. Finally they fasten the cable to
the equipment well enough to pull the equipment off the table when
someone catches the cable - I'd rather that pulled the plug out than
destroyed the monitor!

Slidelocks are so much better if you must have a locking connection -
but they're rarely used.
--
J. P. Gilliver. UMRA: 1960/1985 MB++G.5AL-IS-P--Ch++(p)Ar@T0H+Sh0!:`)DNAf

Hit any user to continue.

In message ,
Lostgallifreyan writes:
"J. P. Gilliver (John)" wrote in
:

cable might drop you down to 1024x768 for example, due
to the fall off in high frequency response (you can try a
high setting, like 1920x1080, but then it would look fuzzy).

50 feet of all but the most expensive cable will drop you well below
that (-:! It's more "ringing" - you get echoes, especially on vertical
lines - than fuzzy, though not that different.


Big fat cables with ferrite beads on each end. If over 25 feet, add a ferrite
bead clamped round the middle. The fat cables individually screen the analog
lines. I tried using a thin one once. Even a 6 foot length of that will be
worse than 50 feet of the good stuff.

I'm not sure if echo images will be worse with vertical cables, but one thing
[]
I didn't mean vertical cables, I meant you get ringing on the images
where there's a vertical line in the image! (At least, more noticeable.)
--
J. P. Gilliver. UMRA: 1960/1985 MB++G.5AL-IS-P--Ch++(p)Ar@T0H+Sh0!:`)DNAf

Hit any user to continue.

"J. P. Gilliver (John)" wrote in
:

I agree, USB feels insecure. But I _hate_ those screws on D-types:
they're always coming off on the connector, and are the devil to do up
when you've got lots of plugs together.

I hate that too, but no matter how nasty it is having to get pliers out or
whatever, I prefer it to having that kind of bulky line having no anchor at
all.

There are nut-spinners, ideal for tightening the chassis hardware so it
doesn't come off on the plug. I keep one of those around exctly for that
task. It only the makers had the wit to make sure that these 'spinner' tools
could fit compaibly over the head of the thumb-gripped screws too, this would
be easy to handle, even in dark and confined spaces. Just shift the cable
with one hand till the spinner turns freely in the other. (The single
greatest annoyance with KVM wiring is the densely packed heavy cabling, and
the friction caused by bending forces. Screw heads that fit like the ones on
the chassis are all that's needed to make using a spinner easy to the point
of being enjoyable, but very few plug screws are even made to an agreed
standard except on the thread end).

Finally they fasten the cable to
the equipment well enough to pull the equipment off the table when
someone catches the cable - I'd rather that pulled the plug out than
destroyed the monitor!


True, but we can anchor cables to table legs with cable ties, or use plastic
screws and spacers (I think I've seen such) that would hold in normal use,
but make a safe break point at need. Anything better than having no firm
anchor, wondering when (never mind 'if') some plug will ease itself out of
joint.

Slidelocks are so much better if you must have a locking connection -
but they're rarely used.


Agreed. I rarely see those, but of two forms, a spring clamp, or a sliding
slot-retention thinger, both would be good.

"J. P. Gilliver (John)" wrote in
:

I didn't mean vertical cables, I meant you get ringing on the images
where there's a vertical line in the image! (At least, more noticeable.)


Oh. Ok. That difference in each axis might be related to the scan
frequencies, but it might also be illusion. I find that a 1px line looks
sharp horizontally, but blurred vertically. If I lean sideways enough to make
my head horizontal, the acreen's horizontal line looks blurred, and its
vertical one looks sharp. This is true for CRT's and LCD's.

In message , MotoFox
confucius-say@enlightenment!to!him!lead!it!for!bangpath!foll ow!man!wise.
UUCP writes:
And it came to pass that J. P. Gilliver (John) delivered the following
message unto the people, saying~

Crosstalk I can understand, but a whistling? That's surely more to do with
bounces (reflections) than crosstalk.

No, it certainly was caused by crosstalk.

Back in the days of Ma Bell (and for a little while afterward) analogue
long-distance telephone switching equipment was controlled by the presence
of a steady 2600-cycle tone on the line, which indicated the specific
[]
Ah. That would indeed put a whistle on the line by crosstalk (and
explains to me why some of the early hacker newsgroups - and the like -
had 2600 in the name). I don't remember ever hearing that whistle, and I
do go back a bit (I'm 51), so perhaps UK/EU systems use(d) a different
method. (I have a feeling it's a DC thing, BICBW.)

(And I re-wrote the sigblock completely in 8859-1 encoding. The only way I
can now come up with to get rid of the blank lines is to just drop it
altogether. All or nothing.)

Does the rewritten version deliberately have the blank lines in?
--
J. P. Gilliver. UMRA: 1960/1985 MB++G.5AL-IS-P--Ch++(p)Ar@T0H+Sh0!:`)DNAf

I can live with doubt, and uncertainty, and not knowing. I think it's much
more *interesting* to live not knowing than to have answers which might be
wrong. - Richard Feynman, in 1981 Horizon interview