Hillsborough
Sheffield
S6 2LL
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experience problems, e.g. with certain MUXES disappearing. First try rescanning your
TV / set top box (do it manually if possible), but if this fails to work check on Transmitter work
or call the reception advice phone numbers. Also see basic digital fault finding.
Oughtibridge television transmitter was opened in 1980 and broadcasts into the Upper
Don valley. It is necessary due to Emley, Belmont and Crosspool TX`s being hidden by the
hills. It is a relay of Emley Moor and is a Vertically polarised C/D group of 39W.
Only the basic four television channels are transmitted, i.e. no C5 or Digital TV, though
this is due to change in September 2011 when the DSO occurs.
Note that only the three basic PSB MUXES will be transmitted from Oughtibridge, not all
six of them. Post DSO all three PSB MUXES will be within the Oughtibridge transmitter`s
original C/D group.
In this area we would put customers on Emley where ever possible (for C5 and Digital) but
as one drops down into the valley this becomes more problematic. However, if one
examines the topography map some people have a view NNW up the Don valley and so
can still get onto Emley even if they live on the valley floor. The mast is quite well hidden
behind Wharncliffe Woods but if one looks closely one can just see the transmitting array
of log periodics above the tree line. The Channel Allocation Guide reveals that all 4
programme channels are transmitted on the same frequencies as both Wincobank and
Dronfield repeaters, though one would not normally get any co-
A single track stub of the ex Great Central Railway (which originally linked Sheffield to
Manchester via the Woodhead tunnel) runs in the valley below. These days it only sees
one train a day running from the steel works at Aldwarke to the plant at Stocksbridge.
How the mighty have fallen, back in the 1840s this railway was one of the first main lines
built in this country and it was electrified at great expense (and six men`s lives....) in 1954.
Con trails over Oughtibridge / Wharncliffe repeater transmitter. Picture Justin Smith (ATV)
Oughtibridge TV transmitter against the setting sun. Picture Justin Smith (ATV)
Graphic showing the use of a repeater / relay transmitter to improve coverage in a valley which lacks the all important “line of sight” from the main transmitter.
Note that the Emley Moor transmissions are shown in yellow (B group) and the
Oughtibridge transmissions in green, for C/D group !
Nearly all repeaters will transmit digital within the same group as their
analogue broadcasts, i.e. your existing aerial will probably work fine.
This is Oughtibridge and it is a good example of a smaller repeater.
A repeater (or relay) is a transmitter which receives a signal
from a main TV transmitter, remodulates it onto a different
set of frequencies and then rebroadcasts it again.
There are about 1105 * of these in the UK , of which 30 are
larger repeaters (like Sheffield). A full list can be found here.
Repeaters are used to transmit into areas which are unable to
receive good signals from the main transmitter. Although most repeaters only broadcast to a relatively small number of people the larger ones can have significant coverage with a tens of thousands of houses receiving from them.
In the case of Oughtibridge the repeater retransmits into the low lying areas of the Don valley around Wharncliffe and Oughtibridge, hence the name. The signal is received from Emley Moor (situated to the NW) using the log periodic at the bottom of the picture and then rebroadcast via the Log array at
the top of the mast into the valley to the South and West.
Repeaters are usually vertically polarised, but about 70 are
horizontal (e.g. Dronfield). Although this represents around 7%
of all repeaters the larger ones (which transmit to far higher
numbers of people) are all vertical, thus probably 99% of people
on repeater transmitters would have aerials vertically polarised.
At DSO (Digital Switchover) the plan is that these smaller
repeaters will only broadcast the three PSB MUXES, not all six of
the MUXES. That will still give all the five channels which are
presently transmitted on analogue, plus a load of others, plus
three or four HDTV channels. But you won`t get all of the
available transmissions.
I wouldn`t worry about it though, most of the extra channels
are rubbish (or repeats) anyway.....
* Source Ofcom Nov 2008 (excludes “self help” transmitters).
Note the broadcast authorities use of Log Periodic aerials (see
close up below). They use them wherever possible, we use
them wherever possible, and so should everyone else !
These aerials are of BBC
design but manufactured by Chelton electronics.
They are 48" long by 13" wide, with 30 elements and a gain
of 6 to 8dBd.
These must be the most ruggedly constructed aerials around and are generally used for broadcasting but also by the military.
They should be well made because they weigh nearly 3kg and cost over £500 each ! ? !
Details N Savin 2009
BBC research department pdfs : Use of Log Periodics for transmitting.
"Ruggedised" Log Periodic (see above).
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