Re: Loftbox users?

[Bruno Prior <bruno@xxxxxxx>]

A little extra info on distribution of terrestrial signal through loftbox:

I have now tried the following:

TV attached direct to feed from aerial (i.e. TV positioned where loftbox
is located but connected direct, rather than through loftbox): As good
as it gets round here (a bit hazy on Ch.5).

TV located by loftbox and fed by short cable run from loftbox: very poor
signal on all channels - snow storm, some black & white and some sound
interference, but a little better than if the TV is disconnected from
the loftbox.

TV located in bedroom and connected direct to aerial by connecting cable
>from
degraded, but some image and sound available for each channel
(snow-storm effect). Better than the previous option.

TV located in bedroom and connected to aerial via the loftbox: No
reception on all but one channel (Ch.4 I think), which is very badly
degraded. If anything, the signal improves when I disconnect the bedroom
cable from the loftbox, but this is marginal. Effectively, no signal is
coming from the loftbox, the minimal reception is presumably due to the
long cable run acting minimally as an antenna.

So I seem to have two problems: (a) signal deterioration on the cable
run from loftbox to bedroom, (b) signal deterioration within the
loftbox. The combination of the two (sending a signal via the loftbox
and a subsequent long cable run) seems to be deadly to the signal.

Just in case I'm making an obvious mistake:
the TV aerial is attached to the TV Ant port;
the feed from satellite LNB1 is attached to Sat Ant;
the Living Room port is connected to the integrated outlet plate
(triplexer) in the living room;
the Sky+ box's LNB1 port is connected to the Satellite port on the
integrated outlet plate;
the Sky+ box's LNB2 port is connected direct to the LNB2 on the dish (or
actually via a barrel connector near the loftbox);
the Sky+ box's RF 2 port is attached to the return feed port on the
integrated outlet plate, which is connected to UHF2 on the loftbox;
the cables from the bedrooms are attached to ports 1 - 4 on the loftbox.

As I understand it, that should be right, so I don't know what's
happening, but the result is certainly not useable. As things stand, I
would certainly recommend against using a loftbox, as, incidentally,
would my Sky installer.

Cheers,

Bruno


Paul Gordon wrote:
> Thanks Bruno. Uselful stuff.
>
> In my case, I think my runs will be a lot shorter. - perhaps 15-20
metres
> from the dish to the loftbox (in the cellar), then no more than 2-3
metres
> from the loftbox to the MSWP in the living room, and the sky+ box will
be no
> more than 1-2 metres away from that. I'll be leaving a couple of
metres of
> slack in the long run from the dish anyway, so if I do find its not
good
> enough, I can easily take the LNB1 cable direct to the Sky+ box
instead.
> TBH, I'm not *that* desperate to distribute sky anyway, as I already
have 2
> digiboxes & 2 subs (1 upstairs, 1 down). The downstairs one used
to
> distribute to the kitchen via the RF2 out, but I've long been
intending to
> replace that with a KAT5 feed anyway and send composite rather than
UHF.
>
> Upstairs I've not bothered distributing the RF2 out from the digibox
up
> there because 99% of the time there's no need to be able to watch in
in any
> of the other bedrooms (I'm not in the doghouse that often!), plus I
also
> didn't want the possibility of guests changing the sky channel from
another
> room as I might be watching in the master bedroom, or more
importantly, TiVo
> might be recording something.
>
> The most useful thing for me is going to be distributing the CCTV, and
> simplifying the mish-mash of coax cables I've built up over the
years...
>
> Paul G.
>
>
>
>
>>From: Bruno Prior <bruno@xxxxxxx>
>>Reply-To: ukha_d@xxxxxxx
>>To: ukha_d@xxxxxxx
>>Subject: Re: [ukha_d] Loftbox users?
>>Date: Fri, 08 Aug 2003 14:17:37 +0100
>>
>>I've just done exactly that (LNB1 via the loftbox, LNB2 direct).
The
>>picture's fine, but I am getting some sound breakup, compared to if
I
>>have the Sky+ box connected direct to LNB1. It's a hell of a long
run,
>>though (around 25 metres of cable from dish to loftbox and at least
as
>>much again from loftbox to intended location in living room), so it
may
>>be that which causes the problem. Is there any such thing as a
booster
>>for digital, that I could add to the line from the loftbox to the
living
>>room?
>>
>>And as for distribution of the terrestrial signal - it's not that
great
>>in my area to start with, but by the time it's covered that
distance via
>>the loftbox, it's either hopelessly degraded or so weak that the TV
>>can't autotune to it at all (at least that's the only reason I can
think
>>of why I don't seem to get any signal at all in some of the rooms).
I
>>need to figure out a solution for that.
>>
>>Cheers,
>>
>>Bruno