Waltham`s pre DSO transmitting array. Note how the MUX 5/6 antennas were almost hidden on the NW face of the mast so as not to broadcast in the direction of Sandy (which is SSE), which would have caused co channel interference with Sandy`s pre DSO transmissions. Post switchover this isn`t a problem, so now Waltham`s transmissions are omnidirectional. I think information on radiation patterns is far too difficult to get hold of, it`s bleedin` ridiculous.
Picture showing the feeder cables which carry the Digital signals up to the transmitters. These feeders are about 6” in diameter and and over 300m long they are very expensive (tens of thousands of pounds each) and there are four of them, two each for the main transmitters and two for the reserve antennas. All the main constituent parts of any main transmitter are duplicated at (great cost one might add) so there is always a back up ready to use. Don`t forget these things provide TV pictures for huge numbers of people, around 1.5 million depend on Waltham.
The biggest transmitters (in terms of approximate population coverage * over 1 million) :
Crystal Palace (London) 11 million
Winter Hill (NW of Manchester) 7 million
Sutton Coldfield (N of Birmingham) 5 million
Emley Moor (NW of Sheffield) 4 million
Black Hill (E of Glasgow) 2.5 million
Pontop Pike (SW of Newcastle) 2 million
Sandy (E of Bedford) 2 million
Rowridge (Isle of Wight) 1.75 million
Belmont (ENE of Lincoln) 1.5 million
Mendip (S of Bristol) 1.5 million
Sudbury (WSW of Ipswich) 1.5 million
Waltham (SE of Nottingham) 1.5 million
Bilsdale (S of Middlesborough) 1.0 million
Craigkelly (N of Edinburgh) 1.0 million
* Based on the BBC estimates from 1977, but I can`t imagine they`re that far out. The last time I looked all the major towns and cities were in the same place as they were in 1977...
For Waltham`s frequencies see its channel allocation guide. This also includes the same data for some of the other major transmitters also receivable within Waltham`s coverage area, namely Sutton Coldfield, Oxford, Sandy, Tacolneston, Belmont, Emley, Chesterfield, Nottingham and Fenton.
The Channel Allocation Guides can be very useful in the diagnosis of co-
Waltham TV Transmitter`s Frequencies/Channel Allocations* (above)
Note the gaps in the table below for channels 31 to 37 and 61 to 68, they`re reserved for “other uses”........
The frequencies given are for (most) digital MUXES, for analogue deduct 3MHz.
* There are a few retune events (temporary MUX reallocations) which may not be shown on these tables.
Waltham`s channels in relation to the UHF TV band and the gain curves of the aerials
Note that MUX 4 is out of the original C/D group of the transmitter.
For Waltham`s frequencies see its channel allocation guide.
Also see other relevant Wideband curves.
Waltham television transmitter (TX) is a "guyed mast" structure 309m in height (see How
High is High ?) and is situated 18 miles SE of Nottingham. The mast is identical to Mendip and Bilsdale. It was built by British Insulated Callender`s Cables (or B.I.C.C) who were responsible for much of the infrastructure built in this country from 1945 up to the 1980s. The company is still going but now called Balfour Beatty. The mast is a tubular structure to the top and has in internal lift, though this is out of use partly due to the accident at Belmont.
The transmitter was originally owned by the BBC before being sold off to Crown Castle then to National Grid Wireless and finally to Arquiva (sic).
Waltham was erected in 1968, or to be more accurate the present structure was put up then. The original fell down in 1967 just before entering service !
Waltham broadcasts ITV Central and the relevant BBC Regional TV programmes from the East Midlands. Its population coverage is around 1.5 million people and many in Nottingham, Leicester, Peterborough, Lincoln, Derby and Mansfield are aligned onto it.
Waltham Transmitter OS Grid Ref SK 809 233
Also see basic digital fault finding.
Switchover occurred at Waltham in Aug 2011.
A 4G clearance retune event is due at Waltham on the 29 May 13
Note the huge increase in power after the switchover.
Being a main transmitter Waltham is horizontally polarised and puts out (up to) 50kW. Originally, for analogue, it was a C/D group but since the advent of digital television it is now (unfortunately) a wideband. However, of the six MUXES only MUX 4 is out of the C/D group and even that may well be receivable in decent signal areas (although this is less likely to apply for some cheap crappy Contract aerials).
There is one interleaved spectrum channel allocated to Waltham, CH26, which may be used for a local Nottingham TV station.
Also, the gap between CHs 31 and 37 may (or may not....) be used at some time in the future for more TV channels, all of these possible channels will be receivable on the same wideband aerial as the basic 6 MUXES.
For Waltham we recommend the DM log for strong signal areas, the Log36 for medium signal areas, the DY14WB for poor signal areas, and the XB22WB for those with the most marginal signals. The dimensions and test performance of the aerials can be found on the relevant tables. If requiring a “high gain aerial” in the loft we recommend the DY14WB over the XB22 because of the former aerial`s smaller size.
We are more than willing to give advice to those actually purchasing from us. Could those only seeking information please just find the answer somewhere on this site, or ring an aerial installer local to them, or call the reception advice phone numbers.
If you`ve found this site informative and, hopefully, interesting as well,