Freesat vs Freeview quality/bitrate

On 08/10/2012 09:07, Brian Gaff wrote:
The question to be answered then is why?

Brian




there's less space on terrestrial than satellite.

--
Gareth.
That fly.... Is your magic wand.

Scott wrote:
On Mon, 08 Oct 2012 21:50:27 +0100, Bill Wright
wrote:

Scott wrote:

I thought loft aerials were definitely not recommended.
Only in locations where they cannot provide a reliable good signal.

Which would seem to be the position Mr Houghton is facing if passing
scooters affect the TV reception.
Not necessarily. It depends on the quality of his present installation.

I doubt if there's much difference between a loft and outdoor aerial for
immunity to impulse interference from the street, assuming that the loft
aerial is properly installed.

Bill

Scott" wrote in message
.. .
On Sun, 7 Oct 2012 15:09:40 +0000 (UTC), Tony Houghton
wrote:

In ,
Scott wrote:

On Sun, 7 Oct 2012 12:56:03 +0000 (UTC), Tony Houghton
wrote:

My PVR has Freeview and Freesat tuners so it would be useful to know
which is better quality when choosing one or the other to make a
recording. AIUI Freesat often has lower bitrates than Freeview for a
given programme, but if and when Freesat's bitrate is about the same
it's the better choice for me because it's less prone to interference.

I though interference was a thing of the past now that the
transmission power has been boosted? Do you have the correct aerial
for your transmitter on the roof with a good quality aerial lead?

I've got a decent double-screened lead but the aerial is only a loft
aerial and very old. The powered splitter and other general clutter
behind the TV probably doesn't help. Passing scooters have always tended
to interfere, and for a while vans and buses etc seemed to interfere
with the HD channels, but that seems OK now.

I thought loft aerials were definitely not recommended. I also
thought aerial amplifiers were not recommended for digital. I
replaced a wideband aerial with the correct aerial group, which made a
difference, albeit small. When you say, is is okay now did the
problem end with digital switchover?

I had an amplified loft aerial fitted in my new house in 2000. External
aerials were prohibited by restrictive covenant on my estate.

It is in a slight shadow of a hill, according to Wolfbane, but it has given
flawless reception both on analogue and digital, despite going via a two-way
splitter to feed two TVs (well, one TV and one PC with a DVB adaptor). I'm
not sure whether it's a wideband aerial or a grouped aerial, but given that
it was installed in the early days of digital TV, I imagine it was designed
for whatever UHF channels the Oxford transmitter used at the time and was
due to use after DSO.

In article , Bill Wright
wrote:
Scott wrote:
On Mon, 08 Oct 2012 21:50:27 +0100, Bill Wright
wrote:

Scott wrote:

I thought loft aerials were definitely not recommended.
Only in locations where they cannot provide a reliable good signal.

Which would seem to be the position Mr Houghton is facing if passing
scooters affect the TV reception.
Not necessarily. It depends on the quality of his present installation.

I doubt if there's much difference between a loft and outdoor aerial for
immunity to impulse interference from the street, assuming that the
loft aerial is properly installed.

I've used a loft UHF antenna some years, and continue to do so. The
combination seem fine even for receiving Durris (78km away).

Ignition interference was fairly common at first. However a combination of
three changes seem to have dramatically reduced this.

1) They wound up the TX powers.

2) I replaced the old co-ax with newer co-ax. The old had sparse braid
despite being low loss. The new has thick braid and foil. So I suspect does
a better job of rejecting pickup.

3) Installed a distribution amp near the antenna, so lifting the signal
level on the rest of the downlead.

However it may be worth commening that although (2) and (3) may be useful,
they also tend to rely on the system being correctly 'unbalanced'. (e.g.
the reason a good antenna should have a 'balun' arrangement.) Having good
shielding in the cable may not fix a problem if something else in the
system is efficiently injecting input into the inner from currents on the
outside of the 'shielding'.

So it may be that (3) didn't help so much because the signal level was
increased, but because it helped the co-ax and receiver to reject
interference reaching the cable.

Does anyone measure this sort of thing and publish the results? Or has it
gone the way of Gordon King, etc?...

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Jim Lesurf wrote:

2) I replaced the old co-ax with newer co-ax. The old had sparse braid
despite being low loss. The new has thick braid and foil. So I suspect does
a better job of rejecting pickup.

A common cause of break up is the use of a cheap flylead of the type
that has moulded-on plugs. These pick up impulse interference from
nearby thermostats, light switches, and in one recent case from the man
next door's vacuum cleaner. They also pick up interference radiated by
the TV set itself.

Bill

In article , Bill Wright
wrote:
Jim Lesurf wrote:

2) I replaced the old co-ax with newer co-ax. The old had sparse braid
despite being low loss. The new has thick braid and foil. So I suspect
does a better job of rejecting pickup.

A common cause of break up is the use of a cheap flylead of the type
that has moulded-on plugs. These pick up impulse interference from
nearby thermostats, light switches, and in one recent case from the man
next door's vacuum cleaner. They also pick up interference radiated by
the TV set itself.

they can also have a horrendous loss on the higher channels. I measured one
that was -24dB on ch 66 - a more reasonable -6dB on ch 40

--
From KT24

Using a RISC OS computer running v5.18

On Tue, 09 Oct 2012 01:59:40 +0100, Bill Wright
wrote:

Scott wrote:
On Mon, 08 Oct 2012 21:50:27 +0100, Bill Wright
wrote:

Scott wrote:

I thought loft aerials were definitely not recommended.
Only in locations where they cannot provide a reliable good signal.

Which would seem to be the position Mr Houghton is facing if passing
scooters affect the TV reception.
Not necessarily. It depends on the quality of his present installation.

I doubt if there's much difference between a loft and outdoor aerial for
immunity to impulse interference from the street, assuming that the loft
aerial is properly installed.

I thought the stronger the signal the less prone it is to
interference, but maybe that's simplistic.

On Tue, 9 Oct 2012 09:11:59 +0100, Mortimer wrote:

External aerials were prohibited by restrictive covenant on my estate.

This **** is just outrageous. What business have developers (or whoever) got
telling you what you can and cannot do to your own house. They've had their money,
so they can **** right off over trying to retain control.
But more fool you for buying the property and again for not disregarding stupid
things like this.
How many of your neighbours have done so?

Scott wrote:

I thought the stronger the signal the less prone it is to
interference, but maybe that's simplistic.

What matters mostly is the ratio between the interference and the
signal. However if the signal is 'weak' (to speak loosely) the receiver
will probably be struggling a bit to decode the signal, so splashes of
noise will probably have a greater effect than if the signal were strong
(and the interference also stronger, in proportion).

Consider a loft aerial. Assuming that the fact that it's lower down than
a roof aerial doesn't mean that it is more screened from the transmitter
by external objects, the signal it receives will be the same as a roof
aerial minus the attenuation of the tiles (or brick) and minus the
de-tuning effects of any nearby objects, or the effects of any nearby
objects encroaching in the capture area.
Assuming that the screening effects of the tile are the same for the
signal path as they are for the interference path, the ratio of the two
will likely remain the same. In fact, loft aerials can be more screened
from the road than from the transmitter, if the building is high up
above the road and close to it, because the path will then be through
the brick walls below the roof, whereas the signal path might be through
nothing but thin slate.

This might be of interest:
http://www.wrightsaerials.tv/article...sat-201007.pdf

Bill

Paul Ratcliffe wrote:
On Tue, 9 Oct 2012 09:11:59 +0100, Mortimer wrote:

External aerials were prohibited by restrictive covenant on my estate.

This **** is just outrageous. What business have developers (or whoever) got
telling you what you can and cannot do to your own house. They've had their money,
so they can **** right off over trying to retain control.
But more fool you for buying the property and again for not disregarding stupid
things like this.
How many of your neighbours have done so?
The builders normally put these things into the agreement so the estate
continues to look nice while they're selling the last few houses. Once
that's done no-one cares. In any case, such covenants are not in
practice enforceable according to my daughter who is a solicitor
specialising in property.
Such a covenant did a me a massive good turn 40 years ago. We were
living in a brand new house and had two new vans parked on the drive. A
jealous neighbour who was a legal exec (untrained apprentice solicitor)
sent us an official looking letter mentioning a covenant about trade
vehicles. We had been on the cusp of moving out because we'd had a
brilliant trading year and had made such a stupid amount of dosh we
could afford a far better place. The letter just made our minds up for
us. It was really lucky it did because we got in just before the market
went ballistic. We sold for £11,750 having made £3k profit in 2 years,
used £10k of savings and got a £10k mortgage. We bought a house at
£32,000 and one year later I had it valued at £44,000. It took four
years to pay off the mortgage. My only regret is that I wasn't even more
daring because I considered a house at £42,000 that is now worth almost
a million. Mind you they've spend a fortune on it. I reckon they've
spent £50,000 on it.

Our first house cost us £2,600. We had £1,300 savings and the rest
mortgage. My dad said the mortgage would be a millstone round our necks
until the day we died. That house sold for £5,750 after three years.

Bill