Mux 56 at Sudbury last night - anyone else have problems?
 

"Doctor D" wrote in message
et...
I don't have LOS - it's hilly in between, and a 10db amplifier is just
perfect for cleaning things up slightly.
SC and EM are almost on the same bearing from here,
A perfect recipe for CCI.

and a more directional
aerial may not help. I'm already using an Anti XG10E/W.
That's actually one of the least directional aerials on the market.

Bill

Mux 56 at Sudbury last night - anyone else have problems?
 

On Mon, 29 Sep 2008 10:55:17 +0100, Doctor D wrote:
I don't currently have time to look at the post DSO channel
allocations for EM - but if they still clash with SC

As far as I can tell, for all DVB-t transmitters now in operation,
and for most of the relays which will be converted (which will only carry
the three PSB multiplexes), the plan is to put the multiplexes on the
channels currently used for analog.

Remember that for main stations Emley Moor and Sutton Coldfield,
the power of the DVB-t transmissions is going to be increased
considerably, so it is essential that they will be broadcasting
on different channels.

According to http://www.ukfree.tv/txdetail.php?a=SK113003

Sutton Coldfield after DSO will transmit on
*C29 C42 C43 C45 C46 C49 *C50 *C51

and http://www.ukfree.tv/txdetail.php?a=SE222128

Emley Moor after DSO will transmit on

C41 C44 *C45 C47 C48 C51 C52 *C56

where * denotes the tentative proposed multiplexes NEW7 and NEW8
which, of course, may very well never happen.

So as you can see post DSO these two main stations will no longer
broadcast on the same channels, except for the possible, proposed
local low-power multiplexes.

Mux 56 at Sudbury last night - anyone else have problems?
 

"J G Miller" wrote in message ...
On Mon, 29 Sep 2008 10:55:17 +0100, Doctor D wrote:
I don't currently have time to look at the post DSO channel
allocations for EM - but if they still clash with SC

As far as I can tell, for all DVB-t transmitters now in operation,
and for most of the relays which will be converted (which will only carry
the three PSB multiplexes), the plan is to put the multiplexes on the
channels currently used for analog.

The main channels will be
Emley 41 44 47 51 48 52
Sutton 43 46 55 42 45 49

The extra ones, as you list below, sound like a bad idea to me.


Remember that for main stations Emley Moor and Sutton Coldfield,
the power of the DVB-t transmissions is going to be increased
considerably, so it is essential that they will be broadcasting
on different channels.
Hypothetically, if two transmitters increased their power by the same amount
the CCI would get neither worse nor better.

Bill

Mux 56 at Sudbury last night - anyone else have problems?
 

"Bill Wright" wrote in message
...

"Doctor D" wrote in message
et...
I don't have LOS - it's hilly in between, and a 10db amplifier is just
perfect for cleaning things up slightly.
SC and EM are almost on the same bearing from here,
A perfect recipe for CCI.

and a more directional
aerial may not help. I'm already using an Anti XG10E/W.
That's actually one of the least directional aerials on the market.

Bill

Is this another example of marketing over engineering then?
According to the Anti website:

XG10E/W acceptance angle 16 degrees
TCX18EW 19 degrees.

Triax Unix 44W 20 degrees

The XG10E/W also scores well on F/B ratio in comparison.

At least they put figures on their website, I couldn't find any figures for
Televes or Blake.

Mux 56 at Sudbury last night - anyone else have problems?
 

"J G Miller" wrote in message ...
On Mon, 29 Sep 2008 10:55:17 +0100, Doctor D wrote:
I don't currently have time to look at the post DSO channel
allocations for EM - but if they still clash with SC

As far as I can tell, for all DVB-t transmitters now in operation,
and for most of the relays which will be converted (which will only carry
the three PSB multiplexes), the plan is to put the multiplexes on the
channels currently used for analog.

Remember that for main stations Emley Moor and Sutton Coldfield,
the power of the DVB-t transmissions is going to be increased
considerably, so it is essential that they will be broadcasting
on different channels.

According to http://www.ukfree.tv/txdetail.php?a=SK113003

Sutton Coldfield after DSO will transmit on
*C29 C42 C43 C45 C46 C49 *C50 *C51

and http://www.ukfree.tv/txdetail.php?a=SE222128

Emley Moor after DSO will transmit on

C41 C44 *C45 C47 C48 C51 C52 *C56

where * denotes the tentative proposed multiplexes NEW7 and NEW8
which, of course, may very well never happen.

So as you can see post DSO these two main stations will no longer
broadcast on the same channels, except for the possible, proposed
local low-power multiplexes.



Thanks. Looks like my installation can stay as it is then.

Mux 56 at Sudbury last night - anyone else have problems?
 

"Doctor D" wrote in message
et...
aerial may not help. I'm already using an Anti XG10E/W.
That's actually one of the least directional aerials on the market.

Bill

Is this another example of marketing over engineering then?
According to the Anti website:

XG10E/W acceptance angle 16 degrees
TCX18EW 19 degrees.

Triax Unix 44W 20 degrees

I tend to think more of the acceptance from the sides and back than from the
angles near where the aerial is pointing. Mind you, I had cause to align one
of these very short 'high gain' wideband aerials the other day and it seemed
so sloppy -- the front lobe was very wide. Felt odd when you're used to a
grouped 18 ele.


The XG10E/W also scores well on F/B ratio in comparison.

I just don't know where these figures come from. I'm certain that a TC18B
(or K when you could get them) will be dramatically better in this respect
than an XG10W. I have great respect for the big XGs --used hundreds -- but
not the little ones.

The answer with Sutton, if you can't get a K, is to use a B and reduce the
length of some of the directors a little bit. It's all documented in this
group somewhere.

I'm afraid I just can't take manufacturers' figures seriously. I'm not
saying they set out to tell lies, it's just that there's so much room for
embelishment. When anything interesting appears on the market I try six or
ten and make my own mind up. Sometimes I do direct comparisions. In some
instances I have bought ten aerials and thrown six away because they are too
bad to use. Less of that nowadays though. I think all the manufacturers are
pretty slick at tweaking their designs empirically. Years ago there were
some grouped high gain aes on the market that were actually worse than
contract 10 eles!

The fact is that if you know what you're doing you can get better gain and
directivity out of two stacked 18ele grouped aerials than any wideband high
gain monster on the market.

Bill

Mux 56 at Sudbury last night - anyone else have problems?
 

On Mon, 29 Sep 2008 08:10:39 +0100, Doctor D wrote:

Every time there's the slightest sniff of a lift, Emley Moor comes crashing
in with Sutton Coldfield giving us grainy analogue reception and very
unreliable DTTV. Such has been the case over the weekend.

Tony Sayer will be here in a minute to remind me that Sky doesn't suffer in
the same way. ;-)

Not exactly, but there will be a sun outage for several minutes on a few
days this coming weekend...

Mux 56 at Sudbury last night - anyone else have problems?
 

On Mon, 29 Sep 2008 15:55:16 +0100, Bill Wright wrote:
Hypothetically, if two transmitters increased their power by the same
amount the CCI would get neither worse nor better.

Good point, but ... I am talking nonsense here ... if the distant
signal become sufficiently strong and the antenna is at just the wrong
position, could you not get destructive interference and no useable
data signal at all?

Mux 56 at Sudbury last night - anyone else have problems?
 

"J G Miller" wrote in message ...
On Mon, 29 Sep 2008 15:55:16 +0100, Bill Wright wrote:
Hypothetically, if two transmitters increased their power by the same
amount the CCI would get neither worse nor better.

Good point, but ... I am talking nonsense here ... if the distant
signal become sufficiently strong and the antenna is at just the wrong
position, could you not get destructive interference and no useable
data signal at all?

It all comes down to the ratio between the two signals.

Bill

Mux 56 at Sudbury last night - anyone else have problems?
 

Paul Ratcliffe wrote:
On Mon, 29 Sep 2008 08:10:39 +0100, Doctor D wrote:

Every time there's the slightest sniff of a lift, Emley Moor comes crashing
in with Sutton Coldfield giving us grainy analogue reception and very
unreliable DTTV. Such has been the case over the weekend.

Tony Sayer will be here in a minute to remind me that Sky doesn't suffer in
the same way. ;-)

Not exactly, but there will be a sun outage for several minutes on a few
days this coming weekend...

I've deliberately sat tuned into Astra 28.2E and waited for the sun to move
behind the birds. It was a total anti-climax. The signal strength and quality
meters on the Digibox didn't even flinch. You get a more dramatic effect
during monsoon rain.

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