Bad reception on BBC Mux only
Mike_Scollan
even display the picture). However, this is only on the BBC mux (Ch
52), All other Channels seem fine.
Why, when the signal comes from the same transmitter, do I get all the
channels bar one? I have only just moved to the Area (S75 Postcode)
so have no idea whether I need to upgrade the ariel. Everything
seemed fine for a couple of days after we moved in but getting
problems now.
Can anyone help/advise please?
Dave Brown
wrote:
It may be the transmitter. This evening I'm having great difficulty
getting anything at all on the ITV1 Mux from Sheffield Cross Pool - it
was fine at lunch time. All the other muxes are working as per usual.
--
Dave
Sheffield, England, UK
da...@gnudawn.co.uk
http://www.gnudawn.co.uk/
John Porcella
"Mike_Scollan" <mikes...@hotmail.com> wrote in message
news:734a446d.03122...@posting.google.com...
> I am getting bad reception (to the point that the digibox does not
> even display the picture). However, this is only on the BBC mux (Ch
> 52), All other Channels seem fine.
>
> Why, when the signal comes from the same transmitter, do I get all the
> channels bar one?
Different power levels could be the reason, or the position on the
transmitting mast of the transmitter.
I have only just moved to the Area (S75 Postcode)
> so have no idea whether I need to upgrade the ariel.
What does a leading brand of washing powder have to do with TV reception?
Everything
> seemed fine for a couple of days after we moved in but getting
> problems now.
It could be weather related, or maybe your aerial has moved.
--
MESSAGE ENDS.
John Porcella
Bill
>even display the picture). However, this is only on the BBC mux (Ch
>52), All other Channels seem fine.
>
You are on Emley of course, and despite being close to that Tx there are plenty
of places in S75 where reception is difficult. It is quite likely that ch52
will drop out first because it is the highest frequency in use and it is
outside the old Group B, which was 39 to 51.
Bill
". . it is impossible to standardise . . the installation of television aerials
without recourse to preliminary tests of a practical nature."
Practical Television 1950
Or as we say in this vulgar age, 'Suck it and see'.
Woody
"Bill" <wrights...@aol.com.co> wrote in message
news:20031223193304...@mb-m14.aol.com...
> >I am getting bad reception (to the point that the digibox does not
> >even display the picture). However, this is only on the BBC mux (Ch
> >52), All other Channels seem fine.
> >
>
> You are on Emley of course, and despite being close to that Tx there are
plenty
> of places in S75 where reception is difficult. It is quite likely that
ch52
> will drop out first because it is the highest frequency in use and it is
> outside the old Group B, which was 39 to 51.
>
> Bill
>
>
Come on Bill, that sounds like a sales pitch being he is in your patch!
The old group B might have been 39-51, but aerials don't just stop receiving
when they get to their limits as you well know. The gain might drop off to
near nothing, but more likely I would suggest it could just conceivably be
causing a very slight ghost, and we all know what effect ghosting has on
DTTV!
Happy New Boxing Day to one and ll.
--
Woody
Mike_Scollan
> >I am getting bad reception (to the point that the digibox does not
> >even display the picture). However, this is only on the BBC mux (Ch
> >52), All other Channels seem fine.
> >
>
> You are on Emley of course, and despite being close to that Tx there are plenty
> of places in S75 where reception is difficult. It is quite likely that ch52
> will drop out first because it is the highest frequency in use and it is
> outside the old Group B, which was 39 to 51.
>
> Bill
Thanks Bill,
Would a wide band aerial remedy this? I'm looking at a Labgear 52
Element High Gain TV aerial. Do you think this might help?
Regards,
Mike
Bill
>plenty
>> of places in S75 where reception is difficult. It is quite likely that
>ch52
>> will drop out first because it is the highest frequency in use and it is
>> outside the old Group B, which was 39 to 51.
>>
>> Bill
>>
>>
>
>
>Come on Bill, that sounds like a sales pitch being he is in your patch!
>
>The old group B might have been 39-51, but aerials don't just stop receiving
>when they get to their limits as you well know. The gain might drop off to
>near nothing, but more likely I would suggest it could just conceivably be
>causing a very slight ghost, and we all know what effect ghosting has on
>DTTV!
>
The response of yagis drops off sharply above the highest design frequency, and
in fact starts to drop off several channels below the highest desgn frequency.
Given that the original poster obviousy has marginal reception conditions it is
quite likely that the 1 or 2dB deficit on channel 52 would be enough to make
that mux misbehave whilst the others continued unscathed. My major point
however was that ch52 is the highest frequency in use, not that it might be
outside the passband of the aerial. The former is more significant.
However, if you tried to receive the ch55 mux from Sutton Coldfield on a Gp B
35 to 53 aerial you would be astonished at the poor response of the aerial. I'm
talking 10dB down here! A lot of people in the West Midlands simply don't
receive that mux. If you compare an Antiference TC18B with a TC18E (35 to 68)
the physical difference is scarecely visible, but the response above ch53 is
dramatically different. This is a good demonstration of how critical element
lengths can be.
I realise that your dig about a 'sales pitch' was meant in fun, but actually it
made me groan because we simply cannot keep up with the work at the moment.
January is pretty well booked up. I don't suppose there's anyone in S. Yorks
with a vehicle and public liabitity insurance who could take on a bit of
installation work, is there?
Merry Christmas
Bill
Bill
Disclaimer
Please note that any message posted by me between 24th December 2003 and 2nd
January 2004 is almost certainly a load of drunken bollocks. This does not
imply that messages posted outside of those dates are not loads of drunken
bollocks.
Bill
>Element High Gain TV aerial. Do you think this might help?
No I definitely wouldn't use a wideband aerial for Emley Moor since all the
muxes are within Gp B, as it now is. Tell me where you are (by email if you
like) and I might be able to help you. I used to do a lot of work for DER in
your postcode area and I know most of the bad spots.
Richard
Bill , just love your disclaimer! keep on telling us like it is !
Richard
Mike_Scollan
Thanks again Bill,
Could nearby Overhead power lines (400Kv) cause a signal blackspot?
About 10 metres (horezontal and ?? vertical) from the aerial?
Street is Medina Way if you know the area.
I thought you said in an earlier post that the BBC Mux (Ch52) was just
outside the 'B' band? If no remedy I may have to go for Sky or Cable
to get decent picture :(
What do you charge for a survey to determine if I would be able to get
an aerial that would correct my problems?
Bill
>About 10 metres (horezontal and ?? vertical) from the aerial?
though. Arcing on the insulators in damp weather seems to affect MF and
sometimes VHF FM, but rarely UHF.
>Street is Medina Way if you know the area.
>
That was a field in my Barnsley DER days! A look at the OS suggests that you
should have absolutely no problem. There's a hill to your west, but isn't the
view towards Emley clear? Can you in fact see Emley from high(ish) ground near
your house, or from anywhere where buildings don't obstruct the view?
>I thought you said in an earlier post that the BBC Mux (Ch52) was just
>outside the 'B' band?
Only for the old aerials. They altered it years ago.
>
>What do you charge for a survey to determine if I would be able to get
>an aerial that would correct my problems?
>
Quite honestly I'd be astonished if you had any problem with DTT. The only
snags with analogue in your area are ghosting in screened locations. Field
strength is ginormous if you can see Emley. I don't suppose you need an
attenuator to reduce the signal? Ch 52 is adjacent to analogue ch51 and it
could be giving your receiver indigestion.
You wouldn't want to pay us to just climb on your roof and do a survey. While
we're there we might as well supply and fit a proper aerial. About £110 + VAT
all in.
Mike_Scollan
> Quite honestly I'd be astonished if you had any problem with DTT. The only
> snags with analogue in your area are ghosting in screened locations. Field
> strength is ginormous if you can see Emley. I don't suppose you need an
> attenuator to reduce the signal? Ch 52 is adjacent to analogue ch51 and it
> could be giving your receiver indigestion.
except for BBC CH52 Mux which is at a 4 ! Could be that the previous
owners had an attenuator put in for terrestrial and I haven't traced
it. (I went into the loft last night and to be honest the cable is a
mess. At least 2 (poor) joints and about 5 metres too long. One joint
just after the cable enters the house through an air brick. This is
putting tension on the cable leading to the aeriel (so I may have a
bad connection at the aeriel). One more joint just before the drop
down the cavity wall to the socket. I might just replace all the
cable first (I didn't know it was so poor when I first posted), and
see how far that gets me. Its only a single story drop (house is a
Bungalow) so I should be able to drag the new cable through to the
aeriel socket with the old cable. Suggestions as to cable
specification?
> You wouldn't want to pay us to just climb on your roof and do a survey. While
> we're there we might as well supply and fit a proper aerial. About £110 + VAT
> all in.
first and I'll let you know how I get on.
>
> Bill
Bill
>first and I'll let you know how I get on.
Ideally change the whole length of the cable.
Use CT100 or HF109 or QC100 copper on copper not that shite they sell as
'satellite cable' with silver foil in it.
Mike_Scollan
>
> Ideally change the whole length of the cable.
> Use CT100 or HF109 or QC100 copper on copper not that shite they sell as
> 'satellite cable' with silver foil in it.
>
> Bill
Got round to replacing cable yesterday.
Replaced whole length from socket output to aerial.
There were 4 joints in the old cable (all with connecttors not cable
to cable direct).
The connection onto the aerial was one of the worst connections
possible. The central sheath had been cut right back so that stray
strands of the shielding were in contact with the central core.
Dropped aerial to roof level to make the connections and wife called
out immediately after I connected (ie before I raised or aligned the
aerial) to say that signal strength was upto a 7! After raising the
aerial and aligning (by sight to about the same as other aerials
around), got signal strength up to steady 8 (accasional fick to 9).
Thanks to all for help
Mike