LPD433

LPD433 (low power device 433 MHz) is a UHF band in which licence free communication devices are allowed to operate. The frequencies correspond with the ITU region 1 ISM band of 433.050 MHz to 434.790 MHz, and operation is mainly limited to CEPT countries. The frequencies used are within the 70-centimeter band, which is traditionally reserved for higher power amateur radio operations in most nations worldwide.

LPD hand-held radios are authorized for licence-free voice communications use in most of Europe using analog frequency modulation (FM) as part of short range device regulations, with 25 kHz channel spacing, for a total of 69 channels. In some countries, LPD devices may only be used with an integral and non-removable antenna with a maximum legal power output of 10 mW.

Voice communication in LPD band was introduced to reduce the burden on the eight PMR446 channels over shorter ranges (less than 1 km) . In some EU countries voice is not allowed over LPD.

LPD is also used by wireless instruments and digital devices such as car keylocks.

ITU Region 1 (Europe)

United Kingdom

In the UK, LPD433 equipment that meets the respective Ofcom Interface Requirement can be used for model control, analogue/digitised voice and remote keyless entry systems. There is significant scope for interference however, both on frequency and on adjacent frequencies, as the band is far from free. The frequencies from 430 to 440 MHz are allocated on a secondary basis to licensed radio amateurs who are allowed to use up to 40 W (16 dBW) between 430 and 432 MHz and 400 W (26 dBW) between 432 and 440 MHz. Channels 1 to 14 are UK amateur repeater outputs and channels 62 to 69 are UK amateur repeater inputs. This band is shared on a secondary basis for both licensed and licence exempt users, with the primary user being the Ministry of Defence.

...
Wikipedia