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Waltham TV transmitter
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, we think...... Information on radiation patterns can be difficult to come across, and I cannot for the life of me understand why it is not more widely publicised.
For details of the transmitting arrays see :
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-
External Links
Waltham transmitter Page at MB21
Waltham transmitter Page at The Big Tower
Waltham transmitter Page on Wikipedia
Digital UK Waltham transmitter
Digital UK details of Central transmitters
Waltham`s channels* in relation to the UHF TV band and the gain curves of the aerials
we recommend for it. DM Log Log40 DY14WB XB22WB
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.
* There may be a few retune events (temporary MUX reallocations) just before and after DSO which are not shown on this graph.

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.
Waltham Transmitter OS Grid Ref SK 809 233
Note, as work takes place on various digital transmitters (to prepare for the DSO) you may
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.
DSO occurred at Waltham between the 17 Aug and the 31 Aug 2011.
Note the huge increase in power after the switchover.
Waltham`s MUXES 4 to 6 will suffer a slight reduction in error correction data from the 4 Apr 12
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 though).
There are two interleaved spectrum channels allocated to Waltham, CH 55 and CH 59. In addition there is a possibility of 2 or 3 more MUXES being transmitted between CHs 31 and 37, all of these possible channels will be receivable on the same wideband aerial as the basic 6 MUXES. Back to the top

For Waltham we recommend the DM log for strong signal areas,
the Log 40 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.