Question about TV aerials (Bill Wright?)
 

In article ,
wrote:
I already have a masthead amp - an elderly Maxview - but I've no idea
what its gain is. Why do you suggest a medium gain amp rather than high
gain?

They don't last forever. If possible try removing it and see if there is
any difference. (Realise this may be difficult) The same can apply to an
aerial and cable - connections etc can get poor with age.

--
*Time is fun when you're having flies... Kermit

Dave Plowman London SW
To e-mail, change noise into sound.

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 13:55, bert wrote:
In article , Andrew
writes
On 25/01/2021 06:14, Adrian Caspersz wrote:
On 25/01/2021 00:01, Dave W wrote:

In your case Freesat is the way to go. I have installed a dish at the
base of a tree at the end of my garden, as it can see over my roof
without being visible in the street.

Â*Council houses used to be identified (allegedly) by them having a
satellite dish attached ...

And a new(-ish) car outside (or 2 or 3).

And a 75" TV on the wall.

and the curtains drawn till 4pm

--
Karl Marx said religion is the opium of the people.
But Marxism is the crack cocaine.

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 13:09, Andrew wrote:
On 25/01/2021 09:39, Paul wrote:
williamwright wrote:

no no no no please don't put it in the loft.

I suggest you check the aerial alignment and make sure it isn't near
anything, then fit a masthead amp of moderate gain (at the aerial)
and see what happens. Even if you change the aerial you'll need a
masthead amp.

Blakes:

Proception proMHD11M 1-Way UHF Medium Gain Masthead Amplifier; 1
Input; 1 Output-16dB

PROPSU11FÂ* 1-Way F-Type Inline Power Supply; 1 Input; 1 Output-12v 100mA

Bill

With an antenna that nice, and at that distance, why isn't
this "just working" ?

That's my first question.

Maybe there's some on-axis multipath ?

Â*Â*Â*Â* Paul

Or original 'builders coax' is full of water and/or
corroded from chimney emissions ?.
As I said earlier: I've replaced all the cable with WF100

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 10:17, The Natural Philosopher wrote:
On 24/01/2021 18:51, charles wrote:
IfÂ* you're in an area that needa masthead amp , forget a loft aerial.
Also, a bigger (multi-element) might just double the signal you are
gettting. You might do better with a higher gain amplifier. Or go for
satellite

Most TVs have plenty of gain these days.

Sensitivity is not the same as gain.


if you have crap signal to noise the only thing that will improve it is
a bigger aerial.

Or increasing the level at a point where the s/n ratio is better, ie at
the masthead.


Boosting **** just leads top bigger **** and/or being overloaded with ****.

Most masthead amps sold have too much gain.

Bill

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 11:49, The Natural Philosopher wrote:
On 25/01/2021 11:22, Roger Hayter wrote:
On 25 Jan 2021 at 10:17:18 GMT, "The Natural Philosopher"
wrote:

On 24/01/2021 18:51, charles wrote:
Â* IfÂ* you're in an area that needa masthead amp , forget a loft aerial.
Â* Also, a bigger (multi-element) might just double the signal you are
Â* gettting. You might do better with a higher gain amplifier. Or go for
Â* satellite

Most TVs have plenty of gain these days.

if you have crap signal to noise the only thing that will improve it is
a bigger aerial.

Boosting **** just leads top bigger **** and/or being overloaded with
****.

A masthead amplifier can improve signal to noise ratio a little
because of
cable loss.Â* A small effect, but if the aerial is nearly good enough
it can be
worthwhile.

It helped noise on old analogue sets but much less so on digital -
especially if the mast head amplifier is overloaded by just one strong
channel in band and is generating intermodulation distortion as a result.

cables may introduce loss, but not much noise.

So I still say that masthead amps have had their day. Only place for an
amp is to feed multiple aerials but that's a distribution amp

+1

Even then you need to be in a very bad signal area not to be able to get
away with a passive splitter. Modern TV tuners are very sensitive now.

--
Regards,
Martin Brown

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 11:22, Roger Hayter wrote:


A masthead amplifier can improve signal to noise ratio a little because of
cable loss. A small effect, but if the aerial is nearly good enough it can be
worthwhile.


It will improve it very nearly as much as the cable loss figure, which
can be considerable. 4dB is a massive amount of difference for digital TV.

Bill

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 11:49, The Natural Philosopher wrote:

cables may introduce loss, but not much noise.

So I still say that masthead amps have had their day. Only place for an
amp is to feed multiple aerials but that's a distribution amp

You have a fundamental misunderstanding.

Reading what you say above, why do you believe that an amplifier can
correct signal loss caused by sharing the signal between several outlets
but it can't correct signal loss caused by cable length?

Bill

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 11:57, Andy Bennet wrote:
On 25/01/2021 02:30, williamwright wrote:
On 25/01/2021 00:01, Dave W wrote:

In your case Freesat is the way to go.

No Channel Four HD.

Bill

Yeah I really miss "Come dine with me" in HD.

For me it's the travel programmes with the scenery, amongst other things.

Bill

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 14:28, The Natural Philosopher wrote:
On 25/01/2021 13:55, bert wrote:
In article , Andrew
writes
On 25/01/2021 06:14, Adrian Caspersz wrote:
On 25/01/2021 00:01, Dave W wrote:

In your case Freesat is the way to go. I have installed a dish at the
base of a tree at the end of my garden, as it can see over my roof
without being visible in the street.

Â*Council houses used to be identified (allegedly) by them having a
satellite dish attached ...

And a new(-ish) car outside (or 2 or 3).

And a 75" TV on the wall.

and the curtains drawn till 4pm

What a set of snobs you are! There will be people in this group who live
in council houses. You must be irritating them greatly.

Bill

Question about TV aerials (Bill Wright?)
 

On 24/01/2021 18:13, wrote:

It looks like I need to replace the aerial with a higher-gain type so
I'm wondering whether to go for a group A multi-boom type ...

Won't a group A aerial - particularly a big one - cripple the COM7
multiplex?

We (31 miles from Crystal Palace) were group A until that multiplex -
just like Ridge Hill - was shifted to C55. It took a LOT of fiddling
with my loft group A Yagi to get COM7 to decode reliably.

PA

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 17:07, Martin Brown wrote:
On 25/01/2021 11:49, The Natural Philosopher wrote:
On 25/01/2021 11:22, Roger Hayter wrote:
On 25 Jan 2021 at 10:17:18 GMT, "The Natural Philosopher"
wrote:

On 24/01/2021 18:51, charles wrote:
Â* IfÂ* you're in an area that needa masthead amp , forget a loft
aerial.
Â* Also, a bigger (multi-element) might just double the signal you are
Â* gettting. You might do better with a higher gain amplifier. Or go
for
Â* satellite

Most TVs have plenty of gain these days.

if you have crap signal to noise the only thing that will improve it is
a bigger aerial.

Boosting **** just leads top bigger **** and/or being overloaded
with ****.

A masthead amplifier can improve signal to noise ratio a little
because of
cable loss.Â* A small effect, but if the aerial is nearly good enough
it can be
worthwhile.

It helped noise on old analogue sets but much less so on digital -
especially if the mast head amplifier is overloaded by just one strong
channel in band and is generating intermodulation distortion as a result.

cables may introduce loss, but not much noise.

So I still say that masthead amps have had their day. Only place for
an amp is to feed multiple aerials but that's a distribution amp

+1

Even then you need to be in a very bad signal area not to be able to get
away with a passive splitter. Modern TV tuners are very sensitive now.

The new Humax Aura is said to be less sensitive than expected.

It seems to have been released with some unacceptable bugs and
unfinished code. If the recent update has improved it I might get
one. My HD-FOX-T2 has decided not to play ball with the iPlayer
so it needs to be replaced.

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 17:57, Peter Able wrote:
On 24/01/2021 18:13, wrote:

It looks like I need to replace the aerial with a higher-gain type so
I'm wondering whether to go for a group A multi-boom type ...

Won't a group A aerial - particularly a big one - cripple the COM7
multiplex?

We (31 miles from Crystal Palace) were group A until that multiplex -
just like Ridge Hill - was shifted to C55.Â* It took a LOT of fiddling
with my loft group A Yagi to get COM7 to decode reliably.

PA

I'm quite surprised you can get C55 on a group A
aerial at that distance.

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 18:13, Andrew wrote:
On 25/01/2021 17:57, Peter Able wrote:
On 24/01/2021 18:13, wrote:

It looks like I need to replace the aerial with a higher-gain type so
I'm wondering whether to go for a group A multi-boom type ...

Won't a group A aerial - particularly a big one - cripple the COM7
multiplex?

We (31 miles from Crystal Palace) were group A until that multiplex -
just like Ridge Hill - was shifted to C55.Â* It took a LOT of fiddling
with my loft group A Yagi to get COM7 to decode reliably.

PA

I'm quite surprised you can get C55 on a group A
aerial at that distance.

Both C48 and C55 required working on.

It took a bit of fiddling in all three dimensions - and a professional
Spectrum Analyser (chuck-out from work) - to get it to work reliably,
but it has worked ever since.

It was fortunate that I could to some degree sacrifice the signals from
the 20-something channels and still get 100% decode from them all.

PA

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 10:18, The Natural Philosopher wrote:
On 24/01/2021 18:58, John Towill wrote:
I cannot get a decent signal here, so I went the satellite route, i am
totally satisfied with it.

I did similar when in a steep valley. Freesat is slightly better than
freeview, if ugly as sin


Does it have 'Dave'?

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 19:21, Fredxx wrote:
On 25/01/2021 10:18, The Natural Philosopher wrote:
On 24/01/2021 18:58, John Towill wrote:
I cannot get a decent signal here, so I went the satellite route, i
am totally satisfied with it.

I did similar when in a steep valley. Freesat is slightly better than
freeview, if ugly as sin


Does it have 'Dave'?

Yes.

Question about TV aerials (Bill Wright?)
 

"Andy Bennet" wrote in message
o.uk...
On 25/01/2021 11:59, The Natural Philosopher wrote:
On 25/01/2021 11:57, Andy Bennet wrote:
On 25/01/2021 02:30, williamwright wrote:
On 25/01/2021 00:01, Dave W wrote:

In your case Freesat is the way to go.

No Channel Four HD.

Bill

Yeah I really miss "Come dine with me" in HD.

that's what i-player and a smart tv is 4



I just poke up with the low res. version.

Where do you poke it up ?

More Heavy Trolling by Senile Nym-Shifting Rodent Speed!
 

On Tue, 26 Jan 2021 08:01:39 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

FLUSH the trolling senile asshole's latest troll**** unread

--
Sqwertz to Rodent Speed:
"This is just a hunch, but I'm betting you're kinda an argumentative
asshole.
MID:

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 02:30, williamwright wrote:
On 25/01/2021 00:01, Dave W wrote:

In your case Freesat is the way to go.

No Channel Four HD.

Bill
or All4 (4on Demand) which is more annoying.

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 16:44, wrote:
On 25/01/2021 13:09, Andrew wrote:
On 25/01/2021 09:39, Paul wrote:
williamwright wrote:

no no no no please don't put it in the loft.

I suggest you check the aerial alignment and make sure it isn't near
anything, then fit a masthead amp of moderate gain (at the aerial)
and see what happens. Even if you change the aerial you'll need a
masthead amp.

Blakes:

Proception proMHD11M 1-Way UHF Medium Gain Masthead Amplifier; 1
Input; 1 Output-16dB

PROPSU11FÂ* 1-Way F-Type Inline Power Supply; 1 Input; 1 Output-12v
100mA

Bill

With an antenna that nice, and at that distance, why isn't
this "just working" ?

That's my first question.

Maybe there's some on-axis multipath ?

Â*Â*Â*Â* Paul

Or original 'builders coax' is full of water and/or
corroded from chimney emissions ?.
As I said earlier: I've replaced all the cable with WF100
Check the centre conductor hasnt snapped inside a connector, caught me
out with a low signal issue !

Question about TV aerials (Bill Wright?)
 

"williamwright" wrote in message
...
On 25/01/2021 14:28, The Natural Philosopher wrote:
On 25/01/2021 13:55, bert wrote:
In article , Andrew
writes
On 25/01/2021 06:14, Adrian Caspersz wrote:
On 25/01/2021 00:01, Dave W wrote:

In your case Freesat is the way to go. I have installed a dish at the
base of a tree at the end of my garden, as it can see over my roof
without being visible in the street.

Council houses used to be identified (allegedly) by them having a
satellite dish attached ...

And a new(-ish) car outside (or 2 or 3).

And a 75" TV on the wall.

and the curtains drawn till 4pm

What a set of snobs you are! There will be people in this group who live
in council houses.

Yes. there certainly is at least one.

You must be irritating them greatly.

Its unlikely with Adam.

Lonely Miserable Cantankerous Auto-contradicting Senile Ozzie Troll Alert!
 

On Tue, 26 Jan 2021 11:49:39 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

FLUSH the trolling senile asshole's latest troll**** unread

--
The Natural Philosopher about senile Rodent:
"Rod speed is not a Brexiteer. He is an Australian troll and arsehole."
Message-ID:

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 17:11, williamwright wrote:
On 25/01/2021 11:49, The Natural Philosopher wrote:

cables may introduce loss, but not much noise.

So I still say that masthead amps have had their day. Only place for
an amp is to feed multiple aerials but that's a distribution amp

You have a fundamental misunderstanding.

Reading what you say above, why do you believe that an amplifier can
correct signal loss caused by sharing the signal between several outlets
but it can't correct signal loss caused by cable length?

I'm with TNP on this one. Modern sets have such sensitive receivers that
the problem is more with their ability to pick up remote transmitters in
a sidelobe instead of the wanted stations in the direct beam.

Masthead amplifiers have largely had their day and for a digital signal
can even sometimes make things worse by partially scrambling it. There
might be some merit in a low gain one if you have horribly lossy cable.
(but replacing the bad old cable would probably be cheaper and better)

My brother in laws TV airspaced coax is full of water this time of year!

--
Regards,
Martin Brown

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 21:01, Rod Speed wrote:


"Andy Bennet" wrote in message
o.uk...
On 25/01/2021 11:59, The Natural Philosopher wrote:
On 25/01/2021 11:57, Andy Bennet wrote:
On 25/01/2021 02:30, williamwright wrote:
On 25/01/2021 00:01, Dave W wrote:

In your case Freesat is the way to go.

No Channel Four HD.

Bill

Yeah I really miss "Come dine with me" in HD.

that's what i-player and a smart tv is 4



I just poke up with the low res. version.

Where do you poke it up ?

Old Essex dialect for "put up with"

Question about TV aerials (Bill Wright?)
 

On 25 Jan 2021 at 22:40:12 GMT, "Robert" wrote:

On 25/01/2021 02:30, williamwright wrote:
On 25/01/2021 00:01, Dave W wrote:

In your case Freesat is the way to go.

No Channel Four HD.

Bill
or All4 (4on Demand) which is more annoying.

A Roku device will provide that for no subscription cost if you have a decent
internet connection.

--
Roger Hayter

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 18:37, Peter Able wrote:
On 25/01/2021 18:13, Andrew wrote:
On 25/01/2021 17:57, Peter Able wrote:
On 24/01/2021 18:13, wrote:

It looks like I need to replace the aerial with a higher-gain type
so I'm wondering whether to go for a group A multi-boom type ...

Won't a group A aerial - particularly a big one - cripple the COM7
multiplex?

We (31 miles from Crystal Palace) were group A until that multiplex -
just like Ridge Hill - was shifted to C55.Â* It took a LOT of fiddling
with my loft group A Yagi to get COM7 to decode reliably.

PA

I'm quite surprised you can get C55 on a group A
aerial at that distance.

Both C48 and C55 required working on.

It took a bit of fiddling in all three dimensions - and a professional
Spectrum Analyser (chuck-out from work) - to get it to work reliably,
but it has worked ever since.

It was fortunate that I could to some degree sacrifice the signals from
the 20-something channels and still get 100% decode from them all.

PA

According to the table for a group A Yagi, you should
not be able to get anything at all in the 48+ range though ?.
And your aerial is loft-mounted too ?. Strange.


https://www.aerialsandtv.com/product/yagi-xb10a-aerial

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 17:07, Martin Brown wrote:

A masthead amplifier can improve signal to noise ratio a little
because of
cable loss.Â* A small effect, but if the aerial is nearly good enough
it can be
worthwhile.

It helped noise on old analogue sets but much less so on digital -

No, because with digital you don't see a snowy picture, you see nowt at all.

Because the difference in signal/noise ratio between good DTT and highly
unreliable DTT is so small, a masthead amp can make a massive difference.

especially if the mast head amplifier is overloaded by just one strong
channel in band and is generating intermodulation distortion as a result.

The chances of having one mux so strong as to overload a modern amp
whilst the others need a masthead amp is so small that I don't think
I've ever encountered it.
Modern amps have a lot of headroom, not that it's needed for that scenario.
It's always important to use a masthead with enough gain, but not too
much. In-band muxes aren't the problem; it's things like mobile phone
base stations.


cables may introduce loss, but not much noise.

So I still say that masthead amps have had their day. Only place for
an amp is to feed multiple aerials but that's a distribution amp

+1

Even then you need to be in a very bad signal area not to be able to get
away with a passive splitter. Modern TV tuners are very sensitive now.


Not a 'very bad' signal area. A 'mediocre' signal area.
Emley Moor, and a village near Retford. Emley is the best tx because of
hills in the way of Belmont. Everyone uses Emley without many problems.
There are no big aerials or other signs of weak reception. Levels are
dBmV (average across Gp B muxes)
Output of a log periodic on the chimney -8
cables loss 3dB so -11
wallplate and flylead loss 2dB so -13.
That's OK because it's still 7db above threshold.
But cut the downlead in the loft and add a splitter to feed a bedroom
and the living room telly is down to -17. That's only just above
threshold. Reception will be unreliable.

Bill

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 18:08, Andrew wrote:
The new Humax Aura is said to be less sensitive than expected.

Thirty years ago Sxxx came out with some tellys that needed masthead
amps even in medium signal areas.

Bill

Question about TV aerials (Bill Wright?)
 

On 26/01/2021 09:38, Martin Brown wrote:
Reading what you say above, why do you believe that an amplifier can
correct signal loss caused by sharing the signal between several
outlets but it can't correct signal loss caused by cable length?

I'm with TNP on this one. Modern sets have such sensitive receivers that
the problem is more with their ability to pick up remote transmitters in
a sidelobe instead of the wanted stations in the direct beam.

Just answer my question: "Why do you believe that an amplifier can
correct signal loss caused by sharing the signal between several
outlets but it can't correct signal loss caused by cable length?"

Regarding your statement: "Modern sets have such sensitive receivers
that the problem is more with their ability to pick up remote
transmitters in a sidelobe instead of the wanted stations in the direct
beam" why would increased receiver sensitivity make that more of a
problem? Two possible meanings of what you say:
1. You mean that the remote signals would be co-channel with the local
ones so would cause interference. But the receiver sensitivity would
have no effect on the signal/noise ratio.
2. You mean that the set would tune to incorrect transmissions. Most
sets allow regional selection. Otherwise it's down to the installation.
It isn't reasonable to blame better sensitivity for this 'problem'.

Incidentally, modern sets are not 'more sensitive'. They have better
decoders, and front ends with lower thermal noise and better protection
against out-of-band signals.

Bill

Question about TV aerials (Bill Wright?)
 

On 25/01/2021 18:13, Andrew wrote:


I'm quite surprised you can get C55 on a group A
aerial at that distance.

A Gp A on those channels will have zero gain over a bit of wire.

Bill

Question about TV aerials (Bill Wright?)
 

In article ,
williamwright wrote:
On 25/01/2021 18:08, Andrew wrote:
The new Humax Aura is said to be less sensitive than expected.

Thirty years ago Sxxx came out with some tellys that needed masthead
amps even in medium signal areas.

Bill


prior to that they had a model that would overload with 12 uhf channels
spread across the band. You couldn't get noise free signals on any chaannel.

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

Question about TV aerials (Bill Wright?)
 

On 26/01/2021 14:31, williamwright wrote:
On 26/01/2021 09:38, Martin Brown wrote:
Reading what you say above, why do you believe that an amplifier can
correct signal loss caused by sharing the signal between several
outlets but it can't correct signal loss caused by cable length?

I'm with TNP on this one. Modern sets have such sensitive receivers
that the problem is more with their ability to pick up remote
transmitters in a sidelobe instead of the wanted stations in the
direct beam.

Just answer my question: "Why do you believe that an amplifier can
correct signal loss caused by sharing the signal between several
outlets but it can't correct signal loss caused by cable length?"

It can provided that the mast head amplifier isn't swamped by other
strong local RF interference. Mast head amplifiers of old almost
invariably have too much gain for their own good. A sharing amplifier is
also much more modest gain and acting more like a low gain buffer.

Regarding your statement: "Modern sets have such sensitive receivers
that the problem is more with their ability to pick up remote
transmitters in a sidelobe instead of the wanted stations in the direct
beam" why would increased receiver sensitivity make that more of a
problem? Two possible meanings of what you say:
1. You mean that the remote signals would be co-channel with the local
ones so would cause interference. But the receiver sensitivity would
have no effect on the signal/noise ratio.

2. You mean that the set would tune to incorrect transmissions. Most
sets allow regional selection. Otherwise it's down to the installation.
It isn't reasonable to blame better sensitivity for this 'problem'.

#2. Particularly in Manchester after digital day the Welsh channels in
the sidelobe of an antenna pointed at Winter Hill were strong enough and
found first to become the defaults on some older Panasonic sets.

You had to unplug the coax while it scanned past the low end.

Incidentally, modern sets are not 'more sensitive'. They have better
decoders, and front ends with lower thermal noise and better protection
against out-of-band signals.

The UHF front end is much more sensitive and lower noise now than any
tuner circuit that would have ever been on a classical analogue set.

--
Regards,
Martin Brown

Question about TV aerials (Bill Wright?)
 

On 26/01/2021 14:43, charles wrote:
In article ,
williamwright wrote:
On 25/01/2021 18:08, Andrew wrote:
The new Humax Aura is said to be less sensitive than expected.

Thirty years ago Sxxx came out with some tellys that needed masthead
amps even in medium signal areas.

Bill


prior to that they had a model that would overload with 12 uhf channels
spread across the band. You couldn't get noise free signals on any chaannel.


I built a system for Reuters when they moved into 200 Grays Inn Road
that had every channel occupied from 40MHz to 860. Then they moved in
with an assortment of tellys...

Years later my systems in prisons that had a lot of channels revealed
that some of the very cheap LG 14" sets coped better than the more
expensive makes in the staff offices.

Bill

Question about TV aerials (Bill Wright?)
 

On 26/01/2021 16:17, Martin Brown wrote:

Just answer my question: "Why do you believe that an amplifier can
correct signal loss caused by sharing the signal between several
outlets but it can't correct signal loss caused by cable length?"

It can provided that the mast head amplifier isn't swamped by other
strong local RF interference.
Well yes, but it's down the the installer to check the spectrum.

Mast head amplifiers of old almost
invariably have too much gain for their own good.
They often still do, because ignorant installers and DIYers think 'the
more gain the better'. Nowadays most MHAs have variable gain. When that
idea came out some had a variable attenuator on the input! Nowadays it's
usually interstage. Still not as good as using a single stage amp of course.


A sharing amplifier is
also much more modest gain and acting more like a low gain buffer.
You'd be surprised. Most don't use efficient splitting. A typical
example currently on sale has gain of about 26dB feeding a stripline
thing, sort of like a printed directional tap-off unit, to feed each
output. The loss is 15dB to each port, then most of the power is dumped
in a terminating resistor!


Regarding your statement: "Modern sets have such sensitive receivers
that the problem is more with their ability to pick up remote
transmitters in a sidelobe instead of the wanted stations in the
direct beam" why would increased receiver sensitivity make that more
of a problem? Two possible meanings of what you say:
1. You mean that the remote signals would be co-channel with the local
ones so would cause interference. But the receiver sensitivity would
have no effect on the signal/noise ratio.

2. You mean that the set would tune to incorrect transmissions. Most
sets allow regional selection. Otherwise it's down to the
installation. It isn't reasonable to blame better sensitivity for this
'problem'.

#2. Particularly in Manchester after digital day the Welsh channels in
the sidelobe of an antenna pointed at Winter Hill were strong enough and
found first to become the defaults on some older Panasonic sets.

Yes, this was a notorious problem. We had the same here. Most of S Yorks
has strong Belmont and Bilsdale, and some areas have Crosspool, all were
Gp A, so to tune Emley you had to pull the aerial out for the first half
of the scan. Some sets insisted on autoscanning in the night and I was
selling a lot of in-line Gp B filters (which sometimes killed Channel 5
on 37.)

Bill

Question about TV aerials (Bill Wright?)
 

Peter Able wrote:

Won't a group A aerial - particularly a big one - cripple the COM7
multiplex?

How long will CH55 be around for? 700MHz auction taking place in March?

Question about TV aerials (Bill Wright?)
 

On 28/01/2021 12:22, Andy Burns wrote:
Peter Able wrote:

Won't a group A aerial - particularly a big one - cripple the COM7
multiplex?

How long will CH55 be around for?Â* 700MHz auction taking place in March?

It's on Death Row, Ofcom licence expires next June. Arqiva can pull it
at very short notice before then (as they did with COM 8)
BTW COM 8 licence is still active, also until 30/6/22, not that Arqiva
will ever bring it back

Question about TV aerials (Bill Wright?)
 

On 28/01/2021 12:52, Mark Carver wrote:
On 28/01/2021 12:22, Andy Burns wrote:
Peter Able wrote:

Won't a group A aerial - particularly a big one - cripple the COM7
multiplex?

How long will CH55 be around for?Â* 700MHz auction taking place in March?

It's on Death Row, Ofcom licence expires next June. Arqiva can pull it
at very short notice before then (as they did with COM 8)
BTW COM 8 licence is still active, also until 30/6/22, not that Arqiva
will ever bring it back

So where will BBC4 HD, News HD etc go ?. Presumably at some
point most people will (or should/could) be watching BBC1,2,
ITV, C4 and C5 in HD, making Freeview 1,2,3,4,5 redundant ?

Question about TV aerials (Bill Wright?)
 

On 28/01/2021 12:52, Mark Carver wrote:
On 28/01/2021 12:22, Andy Burns wrote:
Peter Able wrote:

Won't a group A aerial - particularly a big one - cripple the COM7
multiplex?

How long will CH55 be around for?Â* 700MHz auction taking place in March?

It's on Death Row, Ofcom licence expires next June. Arqiva can pull it
at very short notice before then (as they did with COM 8)
BTW COM 8 licence is still active, also until 30/6/22, not that Arqiva
will ever bring it back

Thanks for that, both. I'd no idea - but have tried to bone up and, is
this right?

All of the re-works have to happen simultaneously for things not to go
wrong?

Using a full HD TV, we'll still get the current quality and quantity of
service?

It'll offer, to Crystal Palace users with a group A aerial, the benefit
of stuff moving from C55 to lower channel numbers?

What's to go wrong ;)

PA

Question about TV aerials (Bill Wright?)
 

On 28/01/2021 16:46, Peter Able wrote:
On 28/01/2021 12:52, Mark Carver wrote:
On 28/01/2021 12:22, Andy Burns wrote:
Peter Able wrote:

Won't a group A aerial - particularly a big one - cripple the COM7
multiplex?

How long will CH55 be around for?Â* 700MHz auction taking place in March?

It's on Death Row, Ofcom licence expires next June. Arqiva can pull it
at very short notice before then (as they did with COM 8)
BTW COM 8 licence is still active, also until 30/6/22, not that Arqiva
will ever bring it back

Thanks for that, both.Â* I'd no idea - but have tried to bone up and, is
this right?

All of the re-works have to happen simultaneously for things not to go
wrong?

Using a full HD TV, we'll still get the current quality and quantity of
service?

It'll offer, to Crystal Palace users with a group A aerial, the benefit
of stuff moving from C55 to lower channel numbers?

What's to go wrong ;)

PA


well from my crystal ball, I expect some of the following:

the conversion of DVB-T muxes to DVB-T2 (that being PSB1, PSB2 ARQ A,
ARB B and SDN. (PSB3 is already T2)

De-duplication of the DVB-T converted to DVB-T2 public service channels
on PSB 1 & PSB 2 muxes vs the public service DVB-T2 channels on PSB3 mux

Both of the above will increase mux data capacity to allow some Mux 7
channels to move to the remaining muxes.

WILDCARD No 1.

The ARQ A, ARQ B and SDN are made into 3 national SFN's (having proven
the concept of a SFN for Mux 7 and 8 on ch's 55 and 56 over the past few
years)

That could produce a new 600 MHz clearance for 5G or create opprtunities
for new Muxes (For the latter, OINK OINK, oh look, theres a jumbo jet of
pigs flying by! :-) )

WILDCARD No 2.


Teh national DTT/Freeview transmitter network gets closed down and
viewers moved to online streaming services (and even Freesat gets closed
too!

Question about TV aerials (Bill Wright?)
 

On 28/01/2021 17:06, S wrote:
On 28/01/2021 16:46, Peter Able wrote:
On 28/01/2021 12:52, Mark Carver wrote:
On 28/01/2021 12:22, Andy Burns wrote:
Peter Able wrote:

Won't a group A aerial - particularly a big one - cripple the COM7
multiplex?

How long will CH55 be around for?Â* 700MHz auction taking place in
March?

It's on Death Row, Ofcom licence expires next June. Arqiva can pull
it at very short notice before then (as they did with COM 8)
BTW COM 8 licence is still active, also until 30/6/22, not that
Arqiva will ever bring it back

Thanks for that, both.Â* I'd no idea - but have tried to bone up and,
is this right?

All of the re-works have to happen simultaneously for things not to go
wrong?

Using a full HD TV, we'll still get the current quality and quantity
of service?

It'll offer, to Crystal Palace users with a group A aerial, the
benefit of stuff moving from C55 to lower channel numbers?

What's to go wrong ;)

PA


well from my crystal ball, I expect some of the following:

the conversion of DVB-T muxes to DVB-T2 (that being PSB1, PSB2 ARQ A,
ARB B and SDN. (PSB3 is already T2)

De-duplication of the DVB-T converted to DVB-T2 public service channels
on PSB 1 & PSB 2 muxes vs the public service DVB-T2 channels on PSB3 mux

Both of the above will increase mux data capacity to allow some Mux 7
channels to move to the remaining muxes.

WILDCARD No 1.

The ARQ A, ARQ B and SDN are made into 3 national SFN's (having proven
the concept of a SFN for Mux 7 and 8 on ch's 55 and 56 over the past few
years)

That could produce a new 600 MHz clearance for 5G or create opprtunities
for new Muxes (For the latter, OINK OINK, oh look, theres a jumbo jet of
pigs flying by! :-) )

WILDCARD No 2.


Teh national DTT/Freeview transmitter network gets closed down and
viewers moved to online streaming services (and even Freesat gets closed
too!


Thanks. I boned up on some of that by reading

https://ukfree.tv/article/1107052554...from_2019_onwa

where they suggest your "some Mux 7 channels" will be six - somewhat
less than COM7 currently carries.

As for wildcard 2, after it has crashed and burned, will someone say
"Hey, let's build a new network based upon super-high-power wireless
beaming simultaneously to every home in the land!"

PA

Question about TV aerials (Bill Wright?)
 

Peter Able wrote:

I boned up on some of that by reading
https://ukfree.tv/

Are you buying salt in bulk?