Have a look
http://www.fridgeshop.net/
And
Introduction of five
The ITC (successor to the ITA/IBA) was instructed by the government to create a fifth terrestrial TV channel, fitting it in where possible within the existing four-channel system. With the crowding of the spectrum, it was decided to make channels 35 and 37 available, in addition to some spare frequencies in other areas. To coincide with this, manufacturers began re-grouping their aerials. The trend is towards the following:
Group A (red) 21 to 37
Group B (yellow) 35 to 53
Group E (brown) 35 to 68
An additional group covering 34 to 40 also exists, as do some very narrow band aerials designed to receive just a few channels, with good gain and good directivity.
Other aerials remained unchanged. Old aerials of groups A, B and E may just manage to receive channels 35 and 37. I have even seen one old Group B aerial that performs adequately on channels 37 to 55.
NTL (successor to the ITA/IBA technical division) won the transmitter contract. In order to save money, some transmitters previously used only for radio and the discontinued band III TV service were used for the transmission of five.
five became available on satellite a few weeks after it was launched, and cable operators were generally quick on the uptake.
Channels 35 and 37 were within the area allocated for non-broadcast purposes, including video recorders and satellite TV decoders. These units had to be adjusted (retuned) to avoid the interference problems which would have resulted. In areas where interference was a possible problem, five themselves commissioned a retuning service, which started in late 1996 and remained available in affected areas for three months after the local transmitter entered programme service. There are, of course, problems with retuning:
In some areas, there is congestion in the band. This is a particular problem in Lichfield's overlap areas with the Wrekin and Waltham, among others. It can be difficult to find a clear channel, especially if there is more than one unit in the aerial lead, and even more so if the retuning range is limited.
If your equipment has been retuned, whether by Channel 5, your dealer or yourself, and you move to a new area, you may find a channel (not necessarily Channel 5) stuck in the way of your equipment, and you will have to retune again.
Many older pieces of equipment have a limited range of retuning, usually covering only channels between 30 and 40. This limits the number of channels available to you for the equipment.
However, there is good news:
Recent video recorders and satellite receivers have an unlimited range of retuning. This is usually done by front panel or remote controls, and a clear channel can usually be found quickly.
Some cable receivers also block signals. These remove the need for retuning.
Some cable companies supply receivers set to a guaranteed clear channel, and all such units are rented, so there is never a problem with retuning.
five themselves at least used to supply signal blockers for any channel on which they transmitted, though in my experience they were usually ineffective.
If you connect your equipment using SCART cables, with the use of some aerial splitters, you need not use the RF output at all, but the insertion of a splitter can cause a signal reduction of 3dB or more. Alternatively, some equipment allows you to turn off the modulator.