Re: Multidrop KAT5 AV Daisy Chain

[Mark Fulford]

Hi Keith

My AV kit is almost all located in a cabinet my lounge. I have a cabinet in
my
loft with a patch panel and hub. My analogue TV and FM and Sky digital
inputs
are sent down from the loft to my AV centre (DVD, Video, Skybox) and then
back
up to the loft where my TV amp is located. This then sends signals out by
coax
via a number of splitters to all rooms. I have 2 further inputs to the amp
from
other rooms (a digital piano and 2nd video) that can also be viewed
anywhere.

I am thinking ahead and believe that the future will move more towards
digital
signals and media and am thinking a large hard disk based server in the
loft,
running software and connected to digital FTA TV, digital Sky and Internet
to
handle all source recording. Other networked PCs would handle writing stuff
to
DVD/CD. The connection of digital still and digital video camera would be
via PC
and a DVD source remaining in my AV centre where my audio equipment is also
housed. I am thinking video library, photo album, Internet media storage
(when
we finally get broadband). Plus PVR facilities for Sky and digital TV. All
this
then needs to be available to TVs and PCs as appropriate.

The most important requirement is to make changes that are improvements and
additions to what I already have. The KAT5 has already started things off
and
helped me to see how I can do some of my ideas in future. The next stage I
will
probably attempt will be to put a large disk server with digital TV card
and PVR
software in my loft cabinet. Your switcher unit may then be useful - if I
could
combine the current single feed from my AV cabinet together with the output
from
my loft server and send both outputs out. Over time I would then move my
Sky box
up to the loft as well (leaving the DVD player) and put a receiver into my
AV
cabinet to enable audio through my amp and speakers.

I am with you on the contribution of wireless (which is why I put so many
wires
in my house). However, I am considering it for portable PC Internet access
and
there may be some other applications in future.

On the switcher unit specifically, it does sound like it will be just the
job. I
may need some flexibility on inputs in terms of a combination of RJ45 and
SCART.
The other main issue is IR transmission. I am aware that you are putting IR
into
the KAT5 modules and that the switcher will respond to these signals.
However, I
am hiding all the modules and my IR transmission is all via mini receivers
in
the ceilings of all rooms. The signals are paralleled together in the loft
and
run down to my AV cabinet. There is a box in the cabinet from which I run
mini
emitters to all the AV equipment. The emitters simply stick onto the
receiving
eyes of the equipment. If you are planning to put an IR receiver on the
switcher
that will be ideal as I can use my room based receivers to control it.

Mark


----- Original Message -----
From: Keith Doxey
To: <a
href="/group/kat5-users/post?postID=iL7MFbS5wAimWQD1QVURmQdQ1SW3MPBMPi74-e8NWQQeRr574bImv1c3WbUCSEGq5fQj_1DYY8nsJTVrysFD613a">kat5-users@xxxxxxx</a>
Sent: Tuesday, June 03, 2003 6:49 PM
Subject: RE: [KAT5] Multidrop KAT5 AV Daisy Chain


Hi Mark,

Is your AV point at a different location to your Node 0 ?

Any sources that dont need physical media to be changed can be located
anywhere as can the switcher.

Regarding Wireless - If the transmission is done as analogue then it would
have to be composite video as there would not be a high enough bandwidth to
support multiple video signals each modulated onto different carrier
frequencies so the quality would not be as high as you currently get from
KAT5.

If the signals are sent as digital then there are different compression
algorithms that can be used to minimise the bandwidth but any form of
compression loses quality. Uncompressed digital video is something like
216Mbit in a studio and can easily be compressed down to around 34Mbit
without any noticable loss in quality. Sky digital often uses 2-4Mbit for
their channels and the artifacts can often be seen on some channels
particularly during fast moving scenes.

The biggest problem with any form of wireless is that there is only a
certain bandwidth available and that is shared by anyone in the vicinity.
The more data you try to send through the air, the more likely it is that
you will get corrupted data. Whilst this can easily be detected and resent
it slows down the throughput and also increases the traffic leadign to more
collisions etc.

Although a cable has a finite bandwidth you can double the available
bandwidth by running another cable along side. Run 100 cables and you have
100x the bandwidth available. That cant be done with wireless.

Whilst wireless technology is expensive, the takeup will be slow. As prices
drop it becomes more popular and congestion of the airwaves gets worse.

This happened with Analogue cordless phones, initially very expensive so
very rare and little problem with interference. Prices dropped, more people
got them and they had to introduce extra channels and security coding to
prevent people making calls on other peoples lines.

Although I do have a vested interest in wired solutions it is also backed
up
by the fact that a wired connection is by far the most reliable method of
connection.

Keith

www.diyha.co.uk
www.kat5.tv


> -----Original Message-----
> From: Mark Fulford [mailto:<a
href="/group/kat5-users/post?postID=LKR2hA5cqi7jtg67kYxJBXqdJRe_5cr2iMgs42rImAZJiji41C3Ma9psvhVsfcSNIeS6K1sCqQ">mark@v...</a>]
> Sent: 03 June 2003 17:55
> To: <a
href="/group/kat5-users/post?postID=iL7MFbS5wAimWQD1QVURmQdQ1SW3MPBMPi74-e8NWQQeRr574bImv1c3WbUCSEGq5fQj_1DYY8nsJTVrysFD613a">kat5-users@xxxxxxx</a>
> Subject: Re: [KAT5] Multidrop KAT5 AV Daisy Chain
>
>
> Looks like I may be struggling to implement multisource. When
> I had my house built I put 8 coax cables to my A/V point, but
> only 2 CAT5. One CAT5 is split between IR and Sky telephone
> and the other is already used for KAT5. Well, they do say you
> never have enough points.
>
> I am thinking that in the not too distant future, the way to
> do this will be with a disk based A/V server in the loft,
> together with Sky box and digital tv box, linked to TVs, PCs
> etc. Your KAT5 technology will be a vital part of that. In
> the meantime, I am more than happy with multisource and
> multizone - albeit one at a time.
>
> One other question. Do you have a view on what kind of speed
> wireless networking will have to reach to support the same
> quality of output as wired?
>
> Mark