Hi Bill (and any other RF enthusiasts out there),

In the Mendip area we've a nasty situation at present:

- In the good ole' analogue days it was Group A.

- After the analogue switch-off (ASO), it'll be Group A
   again (allegedly).

- Meanwhile it's "Group W" and the silly arrangements
   mean the MUXes are so widely spaced so that you can't
   easily pre-empt the switch-off (I think!).

My analysis is that Mendip users in fringe areas needing aerial 
replacements will have to pay twice: Wideband now and Group A
after switch-off. This is on the basis that the unused spectrum will
be flogged off and thus they'll get sommat else heading at them down 
their "W" aerials, if they don't change them after ASO.

For us it's a right PITA. We're in a fringe area, not quite 
line-of-sight to Mendip because of the brow of a hill, but I used to get 
decent diffracted signal with my old Group A Antiference Xtra gain (9 
X-directors, I think). Digital is variable, but generally c**p, and the 
reception isn't good either.

I need to ascend to change the downlead (il a pleut ici, beacoup) , and 
I was going to fit a 12-director Gp. A aerial (same Antiference series, 
only bigger) at the same time, to improve the front-back ratio (radar 
interference from Filton is a nuisance). I'm guessing I prolly can't do 
this coz of the high MUXes, or perhaps I can and just accept the poor RX 
until after ASO. I have a nasty suspicion that the digital RF waveform 
places more constraints on aerial choice than analogue did, so the "fit 
gp. A and add gain" may not hack it.

There appears to be little consensus amongst the 'pros' in the area, and 
unsurprisingly, I don't exactly trust any of 'em. I'll send you some 
pics, but in our nearby roads you'll find UHF Yagis pointing at 
practically all points of the compass, with correspondingly interesting 
polarity and design. There's even a log-periodic that's popped up in the 
last fortnight, sort-of pointing at Kings Weston (but it's not even 
straight!). The poseurs Televes one across the road fell off recently 
(been up for less than a year), which was predictable, and the 
replacement's due to descend any day now (judging by the state of the 
lashing). Thus there is ample evidence of cowboys in the area, but well 
trained cavalry are harder to spot!

What thinkest Thou, O great and learned erector of reception apparatus?

Regards,

Simonm.

PS: We're BS9 4EX if you want to see the contours.
PPS: being really cheeky, do you know of a trustworthy chap in the area who
might visit the roof with an analyser etc.?

-- 
simonm|at|muircom|dot|demon|.|c|oh|dot|u|kay
SIMON MUIR, BRISTOL UK
EUROPEANS AGAINST THE EU                   http://www.eurofaq.freeuk.com/
GT250A'76  R80/RT'86  110CSW TDi'88  www.kc3ltd.co.uk/profile/eurofollie/

"SpamTrapSeeSig"  wrote in message 
news:ypmiBMBsNdmHFwjz@tigger.muircom.demon.co.uk...
> Hi Bill (and any other RF enthusiasts out there),
>
> In the Mendip area we've a nasty situation at present:
>
> - In the good ole' analogue days it was Group A.
>
> - After the analogue switch-off (ASO), it'll be Group A
>   again (allegedly).
>
> - Meanwhile it's "Group W" and the silly arrangements
>   mean the MUXes are so widely spaced so that you can't
>   easily pre-empt the switch-off (I think!).
>
> My analysis is that Mendip users in fringe areas needing aerial 
> replacements will have to pay twice: Wideband now and Group A
> after switch-off. This is on the basis that the unused spectrum will
> be flogged off and thus they'll get sommat else heading at them down their 
> "W" aerials, if they don't change them after ASO.
>
> For us it's a right PITA. We're in a fringe area, not quite line-of-sight 
> to Mendip because of the brow of a hill, but I used to get decent 
> diffracted signal with my old Group A Antiference Xtra gain (9 
> X-directors, I think). Digital is variable, but generally c**p, and the 
> reception isn't good either.
>
> I need to ascend to change the downlead (il a pleut ici, beacoup) , and I 
> was going to fit a 12-director Gp. A aerial (same Antiference series, only 
> bigger) at the same time, to improve the front-back ratio (radar 
> interference from Filton is a nuisance). I'm guessing I prolly can't do 
> this coz of the high MUXes, or perhaps I can and just accept the poor RX 
> until after ASO. I have a nasty suspicion that the digital RF waveform 
> places more constraints on aerial choice than analogue did, so the "fit 
> gp. A and add gain" may not hack it.
>
> There appears to be little consensus amongst the 'pros' in the area, and 
> unsurprisingly, I don't exactly trust any of 'em. I'll send you some pics, 
> but in our nearby roads you'll find UHF Yagis pointing at practically all 
> points of the compass, with correspondingly interesting polarity and 
> design. There's even a log-periodic that's popped up in the last 
> fortnight, sort-of pointing at Kings Weston (but it's not even straight!). 
> The poseurs Televes one across the road fell off recently (been up for 
> less than a year), which was predictable, and the replacement's due to 
> descend any day now (judging by the state of the lashing). Thus there is 
> ample evidence of cowboys in the area, but well trained cavalry are harder 
> to spot!
>
> What thinkest Thou, O great and learned erector of reception apparatus?
>
> Regards,
>
> Simonm.


Mendip land was always group C/D surely?

SpamTrapSeeSig wrote:

> Hi Bill (and any other RF enthusiasts out there),
> 
> In the Mendip area we've a nasty situation at present:
> 
> - In the good ole' analogue days it was Group A.
> 
> - After the analogue switch-off (ASO), it'll be Group A
>   again (allegedly).
> 
> - Meanwhile it's "Group W" and the silly arrangements
>   mean the MUXes are so widely spaced so that you can't
>   easily pre-empt the switch-off (I think!).


If your watching analogue TV in group A, then this isn't
Mendip as that is a group C/D station., suspect it will
be one of its relays which cover Bristol.

Mendip is still a group C/D after ASO.

SpamTrapSeeSig wrote:
> Hi Bill (and any other RF enthusiasts out there),
>
> In the Mendip area we've a nasty situation at present:

<snip>

> PS: We're BS9 4EX if you want to see the contours.

I'm surprised you can't get a good clean signal from Mendip up there
near the Downs. But if you want to keep everything in band now and
after ASO, can you 'see' Ilchester Crescent? B-vertical then, now, and
for ever ;-) .

André Coutanche

Your area is served by Mendip that is group C/D horizontally polarised now, 
and will remain so after the digital switchover. No doubt the aerials 
pointing in all sorts of directions have been erected by cowboys or others 
with no idea. Of course there may be freak reception from relays but you 
correctly say you need an analyzer to get good results in a fringe area. 
When he gets home from work BW may be able to suggest someone reliable  to 
use.

Peter Crosland

In article , m.t6 
<?@?.?.invalid> writes
>SpamTrapSeeSig wrote:
>
>> Hi Bill (and any other RF enthusiasts out there),
>>
>> In the Mendip area we've a nasty situation at present:
>>
>> - In the good ole' analogue days it was Group A.
>>
>> - After the analogue switch-off (ASO), it'll be Group A
>>   again (allegedly).
>>
>> - Meanwhile it's "Group W" and the silly arrangements
>>   mean the MUXes are so widely spaced so that you can't
>>   easily pre-empt the switch-off (I think!).
>
>
>If your watching analogue TV in group A, then this isn't
>Mendip as that is a group C/D station., suspect it will
>be one of its relays which cover Bristol.
>
>Mendip is still a group C/D after ASO.

Sorry, yes, you're right - C/D.

Given that C5 analogue is horrid anyway, it's no loss really (the disty 
chain reduces the quantization levels nastily, it seems):

Currently:
---------
*C37    C54     C55     C56     C58     C59
*C5     C4      Mx2     MxC     BBC1    Mx1

C61     C62     C64     C65     C67
ITV1    Mx A    BBC2    Mx B    Mx D

*strictly-speaking out of band for C/D

After ASO:
---------
C48     C52     C54     C56     C58     C61
C4      C5      P2      C6      P3      P1

Muxes: C="COM" P="PSB"

So I can probably get away with a C/D aerial for now...

Regards,

Simonm.

-- 
simonm|at|muircom|dot|demon|.|c|oh|dot|u|kay
SIMON MUIR, BRISTOL UK
EUROPEANS AGAINST THE EU                   http://www.eurofaq.freeuk.com/
GT250A'76  R80/RT'86  110CSW TDi'88  www.kc3ltd.co.uk/profile/eurofollie/

In article , Peter Crosland 
 writes
>Your area is served by Mendip that is group C/D horizontally polarised now,

You're right (brainstorm on my part - see other post), but C5 throws it 
out (officially W), and it's on half the ERP of t'other analogue 
channels, to complicate things.

>and will remain so after the digital switchover. No doubt the aerials
>pointing in all sorts of directions have been erected by cowboys or others
>with no idea. Of course there may be freak reception from relays but you
>correctly say you need an analyzer to get good results in a fringe area.

That's my thinking - I need to find a good local specialist really!


Regards,

Simonm.

-- 
simonm|at|muircom|dot|demon|.|c|oh|dot|u|kay
SIMON MUIR, BRISTOL UK
EUROPEANS AGAINST THE EU                   http://www.eurofaq.freeuk.com/
GT250A'76  R80/RT'86  110CSW TDi'88  www.kc3ltd.co.uk/profile/eurofollie/

In article , André Coutanche 
 writes
>SpamTrapSeeSig wrote:
>> Hi Bill (and any other RF enthusiasts out there),
>>
>> In the Mendip area we've a nasty situation at present:
>
><snip>
>
>> PS: We're BS9 4EX if you want to see the contours.
>
>I'm surprised you can't get a good clean signal from Mendip up there
>near the Downs. But if you want to keep everything in band now and
>after ASO, can you 'see' Ilchester Crescent? B-vertical then, now, and
>for ever ;-) .

Sadly no - it's too low down, and ISTR the polar pattern is biased 
towards the
shadow of the Mendips i.e. firing predominantly southwards. We can see 
Kingsweston (line-of-sight, only about 2 miles away), but the same 
applies - predominantly firing the opposite way :(.


Regards,

Simonm.

-- 
simonm|at|muircom|dot|demon|.|c|oh|dot|u|kay
SIMON MUIR, BRISTOL UK
EUROPEANS AGAINST THE EU                   http://www.eurofaq.freeuk.com/
GT250A'76  R80/RT'86  110CSW TDi'88  www.kc3ltd.co.uk/profile/eurofollie/

On Jan 25, 12:24 pm, SpamTrapSeeSig  wrote:
> Hi Bill (and any other RF enthusiasts out there),
>
> In the Mendip area we've a nasty situation at present:
>
> - In the good ole' analogue days it was Group A.
>
> - After the analogue switch-off (ASO), it'll be Group A
>    again (allegedly).

As many others have said, it was Group C/D pre-1997, and will be again
after DSO.

http://www.ofcom.org.uk/tv/ifi/tech/dsodetails/westreg.pdf

In article , SpamTrapSeeSig
 scribeth thus
>Hi Bill (and any other RF enthusiasts out there),

Http://www.freesat.co.uk

Job done:)
-- 
Tony Sayer

On Fri, 25 Jan 2008 14:08:54 +0000, tony sayer 
wrote:

>In article , SpamTrapSeeSig
> scribeth thus
>>Hi Bill (and any other RF enthusiasts out there),
>
>Http://www.freesat.co.uk
>
>Job done:)

Freesat is the cowards way out.  Picking out terrestrial signals from
the ether is far more rewarding :-)  Bunging a dish up & pointing it
at a satellite, where's the skill in that?

Marky P.

SpamTrapSeeSig wrote:

> That's my thinking - I need to find a good local specialist really!
> 
> 
> Regards,
> 
> Simonm.
> 

Word of mouth, talk to the neighbours?  which.co.uk local? If you're a 
which member.

Or Local Councils tend to have a "reputable" traders page on their 
websites nowadays.

Richard

In article <xAl$euD21emHFwRx@bancom.co.uk>,
	tony sayer wrote:
> In article , SpamTrapSeeSig
>  scribeth thus
>>Hi Bill (and any other RF enthusiasts out there),

> Http://www.freesat.co.uk

"freesat is broadcast via satellite so it will have brilliant reception
almost everywhere in the UK - only 2% of UK homes are unable to receive
a satellite signal."

2% is a huge number.

-- 
Paul Martin

In article , Paul Martin
 scribeth thus
>In article <xAl$euD21emHFwRx@bancom.co.uk>,
>       tony sayer wrote:
>> In article , SpamTrapSeeSig
>>  scribeth thus
>>>Hi Bill (and any other RF enthusiasts out there),
>
>> Http://www.freesat.co.uk
>
>"freesat is broadcast via satellite so it will have brilliant reception
>almost everywhere in the UK - only 2% of UK homes are unable to receive
>a satellite signal."
>
>2% is a huge number.
>

And that 2% is places where they won't allow dishes...

What I can never understand apart from the odd snobbery we have in the
UK, is why is it OK for a fecking great lump of Thelves bling but a
minidish is a no-no?..

And of course Terrestrial DTV is going to have 98% coverage?..
-- 
Tony Sayer

tony sayer wrote:

> And that 2% is places where they won't allow dishes...
> 
> What I can never understand apart from the odd snobbery we have in the
> UK, is why is it OK for a fecking great lump of Thelves bling but a
> minidish is a no-no?..
> 
> And of course Terrestrial DTV is going to have 98% coverage?..

98.5% apparently ;-)

http://www.ofcom.org.uk/media/news/2005/06/nr_20050601

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

On Fri, 25 Jan 2008 18:13:08 +0000, tony sayer 
wrote:

>And that 2% is places where they won't allow dishes...

...or are shielded by structures or terrain.
-- 
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

In article <+dVsZuF0aimHFwwv@bancom.co.uk>,
   tony sayer  wrote:
> In article , Paul Martin
>  scribeth thus
> >In article <xAl$euD21emHFwRx@bancom.co.uk>,
> >       tony sayer wrote:
> >> In article , SpamTrapSeeSig
> >>  scribeth thus
> >>>Hi Bill (and any other RF enthusiasts out there),
> >
> >> Http://www.freesat.co.uk
> >
> >"freesat is broadcast via satellite so it will have brilliant reception
> >almost everywhere in the UK - only 2% of UK homes are unable to receive
> >a satellite signal."
> >
> >2% is a huge number.
> >

> And that 2% is places where they won't allow dishes...

When these statistics were produced, no-on even thought of that.  The
reason is either terrain or large building screening.


> What I can never understand apart from the odd snobbery we have in the
> UK, is why is it OK for a fecking great lump of Thelves bling but a
> minidish is a no-no?..

> And of course Terrestrial DTV is going to have 98% coverage?..

but not the same 2%

-- 
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11

The message <+dVsZuF0aimHFwwv@bancom.co.uk>
from tony sayer  contains these words:

> In article , Paul Martin
>  scribeth thus
> >In article <xAl$euD21emHFwRx@bancom.co.uk>,
> >       tony sayer wrote:
> >> In article , SpamTrapSeeSig
> >>  scribeth thus
> >>>Hi Bill (and any other RF enthusiasts out there),
> >
> >> Http://www.freesat.co.uk
> >
> >"freesat is broadcast via satellite so it will have brilliant reception
> >almost everywhere in the UK - only 2% of UK homes are unable to receive
> >a satellite signal."
> >
> >2% is a huge number.
> >

> And that 2% is places where they won't allow dishes...

> What I can never understand apart from the odd snobbery we have in the
> UK, is why is it OK for a fecking great lump of Thelves bling but a
> minidish is a no-no?..

I suspect that it is partly because Sky have brainwashed people into
thinking that satellite TV means Sky and many don't want to be
associated with Sky / Murdoch.  

I don't have a dish because I just can't be bothered.

MB

In article , Alan White
 scribeth thus
>On Fri, 25 Jan 2008 18:13:08 +0000, tony sayer 
>wrote:
>
>>And that 2% is places where they won't allow dishes...
>
>...or are shielded by structures or terrain.

Can't think of that many places where you couldn't get round that
problem if required....
-- 
Tony Sayer

In article ,
   tony sayer  wrote:
> In article , Alan White
>  scribeth thus
> >On Fri, 25 Jan 2008 18:13:08 +0000, tony sayer 
> >wrote:
> >
> >>And that 2% is places where they won't allow dishes...
> >
> >...or are shielded by structures or terrain.

> Can't think of that many places where you couldn't get round that
> problem if required....

indeed, "plastique" can be quite useful at times.

-- 
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11

"SpamTrapSeeSig"  wrote in message 
news:ypmiBMBsNdmHFwjz@tigger.muircom.demon.co.uk...
> Hi Bill (and any other RF enthusiasts out there),
>
> In the Mendip area we've a nasty situation at present:

It's a problem, balancing the requirement now with the situation post-ASO. I 
tend to be biased towards present requirements for a number of reasons:
1. The customer/end user wants results now.
2. The period left before ASO here is still a significant portion of an 
aerial's lifespan.
3. The situation re post-ASO frequency use of the channels that the govt. is 
going to steal is still unclear.

I have sometimes explained to customers/end users that unfortunately the 
installation done today will most likely need to be modified at ASO, and of 
course this will cost money. This is no-one's fault and it can't be helped.

I know that most of you reading this will be thinking about the aerial, but 
a much bigger problem will arise with channelised head-end equipment. This 
is going to present a lot of serious problems during the immediate pre- and 
post-ASO period.

Obviously if there's no strong reason for doing the job in a way that isn't 
compatible with assumed post-ASO requirements then I wouldn't do it that 
way. If field strength is adequate a log-periodic is often the safest 
choice.

I think we should remember that post-ASO DTT field strengths will be higher, 
and this will, in practice, allow all sorts of slightly incorrect 
installations to work just fine. Although I have an instinctive preference 
for things being 'right' I also take the pragmatic view that if something 
works then there's no point is spending money on it. Especially other 
people's money. This males me think of the phenomenon of 'vanity aerial 
rigging', which has been much on my mind of late.

I don't think though that we should get too carried away with the idea that 
post-ASO DTT field strengths will solve every problem. I'm expecting a whole 
host of new CCI problems, and of course it doesn't matter how high the field 
strength, long-delay multipath will have just the same effect.

> And that 2% is places where they won't allow dishes...
>
> What I can never understand apart from the odd snobbery we have in the
> UK, is why is it OK for a fecking great lump of Thelves bling but a
> minidish is a no-no?..
>
> And of course Terrestrial DTV is going to have 98% coverage?..
> -- 
> Tony Sayer
>

I think it's simpler than that Tony - multiple TV's and recorders in single 
properties.

Get Freeview via an aerial and distribute it to many rooms via a fairly 
cheap loftbox or masthead distributor. Buy a receiver for £25 or a DTTV for 
£150+
Get FreeSky and have to buy multiple receivers at far more than £25 each, 
and there's not much in the way of TV's and recorders with Sky built in - 
(any?)

FreeSat may become more viable after the demise of analogue terrestrial TV, 
but not many families could easily do without an aerial now without 
incurring some compromise.

"Marky P"  wrote in
message news:nnujp35kd6fe2qkkrdihactnvjrkop1ljs@4ax.com

[snip]

: : Freesat is the cowards way out.  Picking out
: : terrestrial signals from the ether is far more
: : rewarding :-)  Bunging a dish up & pointing it at a
: : satellite, where's the skill in that?

<rant>
Yeah, it's like all the internet linking that pervades amateur radio these 
days, every time I listen to my local 2m repeater I can hear a couple of 
idiots out in the boondocks of the good ol' US of A yakking to one another 
totally oblivious of the fact that they're stopping dozens of repeaters 
across the world from doing what repeaters are *supposed* to do, i.e. 
facilitate *mobile* communications.
</rant>

In article , Doctor D
 scribeth thus
>
>> And that 2% is places where they won't allow dishes...
>>
>> What I can never understand apart from the odd snobbery we have in the
>> UK, is why is it OK for a fecking great lump of Thelves bling but a
>> minidish is a no-no?..
>>
>> And of course Terrestrial DTV is going to have 98% coverage?..
>> -- 
>> Tony Sayer
>>
>
>I think it's simpler than that Tony - multiple TV's and recorders in single 
>properties.
>
>Get Freeview via an aerial and distribute it to many rooms via a fairly 
>cheap loftbox or masthead distributor. Buy a receiver for £25 or a DTTV for 
>£150+
>Get FreeSky and have to buy multiple receivers at far more than £25 each, 
>and there's not much in the way of TV's and recorders with Sky built in - 
>(any?)
>
>FreeSat may become more viable after the demise of analogue terrestrial TV, 
>but not many families could easily do without an aerial now without 
>incurring some compromise. 
>
>

Ok points taken its a pity that the introduction on digital TV has been
a real doggies din dins..

Here we have a situation where a good few national and public channels
could have been received off the Sky platform in proper HD less too many
compression artyfacts and we still aren't at that situation as yet..

So much rooftop bling in the meantime...
-- 
Tony Sayer