Antiference XG16CD alternative?

On Fri, 07 Nov 2008 03:20:33 +0000, Bill Wright wrote:

"Jonathan Buzzard" wrote in message
...
On Wed, 05 Nov 2008 04:16:27 +0000, Bill Wright wrote:

"Jonathan Buzzard" wrote in message
...
Well the system is based around a Antiference ISYS7. I would have
preferred something with less outputs as 12 is overkill,
The outputs fail one at a time so a few spare is good.


That does not sound good.

All multiswitches are the same in this respect.

I think I may have found a source of the XG16CD so I will try it without
filters first, and if that gives satisfactory results skip them. I could
get away with far less if I was not shooting for a loft mount.
Oh well, if you put a big high gain aerial in the loft the performance will
be reduced.

However the
North Sea is only 500m away, and looking round the neighbour hood, most of
the aerials are in poor condition.
Oh, make life easy and put the bloody thing on the roof where it belongs. By
the time it rots away you will probably be dead. Stop worrying. Honestly Gp
CD in a loft is bad news. An XG16 in the loft won't work as well as a 10
element on the roof.


Yeah, yeah, so everyone says. However I have always been able to get a
perfectly preforment solution in the loft. Sure I have to spend more money
upfront on aluminium but it always works.

Consequently I will always maintain that *if* you can get a working
solution in the loft it is superior to any outside solution. No need to
worry about the effects of the elements on the aerial. No loss of
reception in the dead of winter as some gale blows it away. No need to
worry about great big sea gulls deciding to use it as a perch :-) Finally
in the unlikely event of that any maintenance is required, easy access.

Besides this loft is large enough to take a XG16 or DAT75 with consummate
ease, there are no pipes, and the ancient water tank that is no longer in
use will shortly be removed.

I was even wondering about getting the skylight re-glazed in acrylic and
mounting the satellite dish in the loft :-)


JAB.

--
Jonathan A. Buzzard Email: jonathan (at) buzzard.me.uk
Fife, United Kingdom.

"Jonathan Buzzard" wrote in message
...
Yeah, yeah, so everyone says.
Are you petulant teenager?

However I have always been able to get a
perfectly preforment solution in the loft. Sure I have to spend more money
upfront on aluminium but it always works.
Just out of interest, could you explain 'always'?


Consequently I will always maintain that *if* you can get a working
solution in the loft it is superior to any outside solution.
Agreed, although you'd be surprised at how many loft aerials seem to be OK
for a while, but play up occasionally. This is really the problem with them.
Even in a really bad reception area it's often possible to get a decent
result, but it doesn't last.
You over-rate the problems of external aerials. The vast majorty are
installed, sit up there for 15 or 25 years, then have to be replaced.
Nothing else occurs.
I'm not anti-loft aerial. I've installed many hundreds of loft aerials.
Actually I dread to think how many because for years (during the 70s and
80s) one of the local councils near here insisted on having a loft aerial in
every house and bungalow they built, and they built a great many, and I put
a loft aerial in every one. There's quite an art to it, although if you've
been lucky, which you obviously have, you've probably say there's nothing to
it. I'd say that it's surprising how a bit of time spend investigating all
posible locations can pay off.

Bill

On Sun, 09 Nov 2008 14:40:26 +0000, Bill Wright wrote:
I'm not anti-loft aerial.

Putting aside the issue of metallic objects in the loft space,
which in more modern houses should not be as significant a problem with
the replacement of metal water tanks with plastic ones, is not the most
significant factor is whether or not the direction of the transmitter
is directly through the roof tiles rather than through brickwork into
the adjacent semi-detached house, or whole row of houses?

Clearly if there is metal foil insulation used under the roof tiles,
then it is just not going to work.

And presumably roof tiles are more translucent to UHF signals
than slates?

In message , J G Miller wrote
On Sun, 09 Nov 2008 14:40:26 +0000, Bill Wright wrote:
I'm not anti-loft aerial.

Putting aside the issue of metallic objects in the loft space,
which in more modern houses should not be as significant a problem with
the replacement of metal water tanks with plastic ones, is not the most
significant factor is whether or not the direction of the transmitter
is directly through the roof tiles rather than through brickwork into
the adjacent semi-detached house, or whole row of houses?

Surely there is a lot of metal work in a modern loft with all the
timbers being joined with nail/connector plates?
--
Alan
news2006 {at} amac {dot} f2s {dot} com

"J G Miller" wrote in message ...
Putting aside the issue of metallic objects in the loft space,
which in more modern houses should not be as significant a problem with
the replacement of metal water tanks with plastic ones, is not the most
significant factor is whether or not the direction of the transmitter
is directly through the roof tiles rather than through brickwork into
the adjacent semi-detached house, or whole row of houses?

Clearly if there is metal foil insulation used under the roof tiles,
then it is just not going to work.

And presumably roof tiles are more translucent to UHF signals
than slates?

Yes. To be honest, if I arrive to install a loft aerial and there is a brick
gable in exactly the wrong place I know that itn't going to work. In effect
the installation has terrible directional characteristics, with the
difference in attenuation between the brickwork and the tile countering to
aerial's own properties.
When you're in a loft with a meter and an aerial it all becomes ever so
obvious. Put the aerial where there's a wall in the way and the signal level
drops. Move it to one side so the wall isn't in the way and it climbs.
You should always look outside along the signal path before attempting a
loft ae. If there's an obstruction to one part of the loft it will save you
time if you suss it out beforehand.

Bill

"Alan" wrote in message
...
In message , J G Miller wrote
On Sun, 09 Nov 2008 14:40:26 +0000, Bill Wright wrote:
I'm not anti-loft aerial.

Putting aside the issue of metallic objects in the loft space,
which in more modern houses should not be as significant a problem with
the replacement of metal water tanks with plastic ones, is not the most
significant factor is whether or not the direction of the transmitter
is directly through the roof tiles rather than through brickwork into
the adjacent semi-detached house, or whole row of houses?

Surely there is a lot of metal work in a modern loft with all the timbers
being joined with nail/connector plates?

Proximity of mains cables is a problem. Plastic tanks contain water, as do
many plastic pipes.

Bill

J G Miller wrote:
On Sun, 09 Nov 2008 14:40:26 +0000, Bill Wright wrote:
I'm not anti-loft aerial.

Putting aside the issue of metallic objects in the loft space,
which in more modern houses should not be as significant a problem with
the replacement of metal water tanks with plastic ones, is not the most
significant factor is whether or not the direction of the transmitter
is directly through the roof tiles rather than through brickwork into
the adjacent semi-detached house, or whole row of houses?

Clearly if there is metal foil insulation used under the roof tiles,
then it is just not going to work.

And presumably roof tiles are more translucent to UHF signals
than slates?

Some roof tiles are more translucent than others. For instance reddish tiles
are so because they've been impregnated with oxide, making them particularly
RF unfriendly.

Also, you're likely to have more success with loft reception if your UHF
signals are in Band IV (Ch 21-34) than the top end of Band V ( Ch60).


--
Mark
Please replace invalid and invalid with gmx and net to reply.

In article , Jonathan Buzzard
scribeth thus
On Fri, 07 Nov 2008 03:20:33 +0000, Bill Wright wrote:

"Jonathan Buzzard" wrote in message
...
On Wed, 05 Nov 2008 04:16:27 +0000, Bill Wright wrote:

"Jonathan Buzzard" wrote in message
...
Well the system is based around a Antiference ISYS7. I would have
preferred something with less outputs as 12 is overkill,
The outputs fail one at a time so a few spare is good.


That does not sound good.

All multiswitches are the same in this respect.

I think I may have found a source of the XG16CD so I will try it without
filters first, and if that gives satisfactory results skip them. I could
get away with far less if I was not shooting for a loft mount.
Oh well, if you put a big high gain aerial in the loft the performance will
be reduced.

However the
North Sea is only 500m away, and looking round the neighbour hood, most of
the aerials are in poor condition.
Oh, make life easy and put the bloody thing on the roof where it belongs. By
the time it rots away you will probably be dead. Stop worrying. Honestly Gp
CD in a loft is bad news. An XG16 in the loft won't work as well as a 10
element on the roof.


Yeah, yeah, so everyone says. However I have always been able to get a
perfectly preforment solution in the loft. Sure I have to spend more money
upfront on aluminium but it always works.

Consequently I will always maintain that *if* you can get a working
solution in the loft it is superior to any outside solution. No need to
worry about the effects of the elements on the aerial. No loss of
reception in the dead of winter as some gale blows it away. No need to
worry about great big sea gulls deciding to use it as a perch :-) Finally
in the unlikely event of that any maintenance is required, easy access.

Besides this loft is large enough to take a XG16 or DAT75 with consummate
ease, there are no pipes, and the ancient water tank that is no longer in
use will shortly be removed.

I was even wondering about getting the skylight re-glazed in acrylic and
mounting the satellite dish in the loft :-)


Has been done and does work and if its low lead glass that will work too
but you might need a bigger dish for that far North and something to
remove the seagull **** from it..

JAB.


--
Tony Sayer

"Mark Carver" wrote in message
...
Some roof tiles are more translucent than others. For instance reddish
tiles are so because they've been impregnated with oxide, making them
particularly RF unfriendly.

Standing snow on a roof can cause a 20dB drop. Mysteriously, it often
doesn't.

Bill

In article ,
J G Miller wrote:
On Sun, 09 Nov 2008 14:40:26 +0000, Bill Wright wrote:
I'm not anti-loft aerial.

Putting aside the issue of metallic objects in the loft space,
which in more modern houses should not be as significant a problem with
the replacement of metal water tanks with plastic ones,

but the lump of water is still there!

is not the most
significant factor is whether or not the direction of the transmitter
is directly through the roof tiles rather than through brickwork into
the adjacent semi-detached house, or whole row of houses?

Clearly if there is metal foil insulation used under the roof tiles,
then it is just not going to work.

And presumably roof tiles are more translucent to UHF signals
than slates?

not if they are red concrete ones - the red is iron oxide (rather metallic)
- and some larger concrete ones have metal reinforcing rods in them (to
cope with people walking on them).

--
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11