Six Digital Channels
 

Steve Thackery wrote:
I have a Freeview box (BT badged Netgem) that gives a signal strength,
quality and SNR reading for each channel.

Should these readings be similar on all six channels.

No. Some transmitters use different output powers on the different muxes.
Be aware that some of the muxes use QAM64, which almost always gives a
poorer "signal quality" reading.

Yes, I had seen that mentioned before.

Geoff Lane

Six Digital Channels
 

Max Demian wrote:

I have a Freeview box (BT badged Netgem) that gives a signal strength,
quality and SNR reading for each channel.

Should these readings be similar on all six channels.

I think they are all transmitted at the same strength, but local conditions
and aerial configuration may cause them to differ significantly.

So long as they are adequate for picture and sound without breakups, I
wouldn't worry.

My daughter at HP1 (Hemel Hempstead) gets an occasional break up for a
considerable time period.

The freeview box shows good quality signal, I am thinking it could be
some local interference.

Geoff Lane

Six Digital Channels
 

"Geoff Lane" wrote in message

Mark Carver wrote:

I have a Freeview box (BT badged Netgem) that gives a signal
strength, quality and SNR reading for each channel.

Should these readings be similar on all six channels.

Some transmitters have the six muxes at different output powers,
and/or some muxes are restricted in some directions from the
transmitter, so it depends which transmitter you are referring to.

Crystal Palace

All the muxes from there are 20 kW.

Which ones appear to be weaker?

--
Max Demian

Six Digital Channels
 

In article ,
Max Demian wrote:
"Geoff Lane" wrote in message

Mark Carver wrote:

I have a Freeview box (BT badged Netgem) that gives a signal
strength, quality and SNR reading for each channel.

Should these readings be similar on all six channels.

Some transmitters have the six muxes at different output powers,
and/or some muxes are restricted in some directions from the
transmitter, so it depends which transmitter you are referring to.

Crystal Palace

All the muxes from there are 20 kW.

but are they all coming from the same tx aerial? I thought some were from
lower down the tower.

Which ones appear to be weaker?

--
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11

Six Digital Channels
 

charles wrote:
In article ,
Max Demian wrote:

Crystal Palace

All the muxes from there are 20 kW.

but are they all coming from the same tx aerial? I thought some were from
lower down the tower.

Wolfblane's site lists all six muxes at CP as 321 metres AOD.

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

Six Digital Channels
 

In article ,
Mark Carver wrote:
charles wrote:
In article ,
Max Demian wrote:

Crystal Palace

All the muxes from there are 20 kW.

but are they all coming from the same tx aerial? I thought some were
from lower down the tower.

Wolfblane's site lists all six muxes at CP as 321 metres AOD.

is that info as trustworthy as the rest of theirs?

--
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11

Six Digital Channels
 

charles wrote:
In article ,
Mark Carver wrote:

Wolfblane's site lists all six muxes at CP as 321 metres AOD.

is that info as trustworthy as the rest of theirs?

Fair point ! I've just dug out a paper copy of a 1998 ITC planning document,
that gives 211 metres above ground level for all six muxes.

Next question, is the ground at CP really 110 metres AOD ?

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

Six Digital Channels
 

On Sun, 17 Jun 2007 14:02:30 +0100, Mark Carver
wrote:

Next question, is the ground at CP really 110 metres AOD ?

No, the 1:50,000 OS map gives it as 111 metres ;-)

--
Alan White
Mozilla Firefox and Forte Agent.
Twenty-eight miles NW of Glasgow, overlooking Lochs Long and Goil in Argyll, Scotland.
Webcam and weather:- http://windycroft.gt-britain.co.uk/weather

Six Digital Channels
 

Max Demian wrote:


I have a Freeview box (BT badged Netgem) that gives a signal
strength, quality and SNR reading for each channel.

All the muxes from there are 20 kW.

Which ones appear to be weaker?

Crystal Palace Ch 25 and 28 which were stable, all the others were
showing erratic signal quality.

Most of time the picture on all channels is fine.

Geoff Lane