More Information

For Trade only

How to interpret the Trade view of the Postcode Checker

The Trade view provides comprehensive details of television reception options for an address or postcode based on the nearest prediction point to the address or postcode centroid. The DTT predictions are those which are being used to plan the DTT network, and assume a representative receiving system in good condition. Predictions can vary significantly over a short distance due to the effects of terrain and interference, so they should be treated as a guide to the likely situation on the ground.

The checker does not include information about self-help transmitters.

Analogue Transmitters

Information relating to the analogue transmitters which could potentially be in use at the address are listed:

• The 'most likely' transmitter to be in use, derived from a complex algorithm. Note that this may not be the transmitter in use, and it is not always possible to identify a most likely transmitter.
• The distance to and bearing of the transmitter from the address
• The transmission channels, listed in the order BBC One, BBC Two, ITV1, C4/S4C and C5.
• The analogue aerial group and polarisation

Digital Transmitters

Information relating to the digital transmitters which are, or are likely to be, receivable at the search address:

• The 'most likely' transmitter to be in use. This will be the same as the 'most likely' analogue transmitter, providing that transmitter provides coverage after switchover.
• The distance to and bearing of the transmitter from the address
• The published switchover date
• The digital aerial group and polarisation a) now b) after switchover

Prediction

The Prediction section details the transmission channels and a multiplex-by-multiplex coverage prediction for each transmitter that is predicted to provide a usable signal (i.e. a prediction of at least 50) on at least one multiplex at the address or postcode centroid at any time during the switchover process. The prediction is repeated for each step where coverage changes significantly.

Two predictions are provided:

1. where the signal meets the planning standard
2. where the signal may be subject to periodic interference, but may still be usable

The higher the prediction figure, the better the reception margin.

Example:

Mux 1, Mux 2, Mux B, Mux C and Mux D are flagged as green because they provide a good quality service with planning standard predictions in excess of the threshold of 70. The predictions at the periodic interference level are irrelevant in this situation, but will always be the same as, or higher than, the planning standard predictions.

Mux A is flagged as amber. This is because the coverage prediction of 57 at the planning standard does not meet the threshold of 70, and so the address is officially unserved by this multiplex. In this situation, the predictions at the periodic interference level become useful. Mux A has a coverage prediction of 99 at the periodic interference level which indicates that there is sufficient signal to receive the service, but it is likely to be subject to periodic interference. A decision can be made as to whether this reduced quality of service will be acceptable.

Other platforms

Information relating to the current availability of other digital television platforms in the postcode, as provided to Digital UK by the relevant platform provider. Note that in general, predictions of future coverage are not available. The limitations of cable and DSL network coverage means that availability to a specific address needs to be confirmed with the relevant platform provider.

Planning Standard

The prediction is made at the centre of a 100m x 100m tile. Based on the use of a representative antenna of the correct type and in good condition at 10m above ground level, the signal is predicted to be receivable without interference from co-channel transmissions for at least 99% of the time to the proportion of the tile indicated, measured in %. The UK planning standard is met where at least 70% of the tile is served in this way, i.e. for values between 70 and 100.

Periodic Interference

The prediction is made at the centre of a 100m x 100m tile. Based on the use of a representative antenna of the correct type and in good condition at 10m above ground level, the signal is predicted to be receivable without interference from co-channel transmissions for between 50% and 99% of the time to the proportion of the tile indicated, measured in %. While this does not meet the UK planning standard for service reliability, the level signal may be usable and the level of service acceptable to a consumer.

Channel

The radio frequency channel number currently allocated to this multiplex. Note that the digital spectrum plan is still being developed and both channel numbers and the way they are allocated to specific multiplexes are liable to change, particularly for regions which are later in the switchover programme.