Standard frequency and time transmissions, Boundaries of sea areas and UK CB radio.

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Standard frequency and time transmissions

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Standard frequency formats

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Boundaries of sea areas

As used in BBC and BT weather forecasts

Stations whose latest reports are broadcast in the 5 minute forecasts on Radio 2 (200 kHz) at 0033, 0633 and 1755 (daily), 1155 (Sundays) and 1355 (weekdays).

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The SINPFEMO code

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The SINPO code

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The SIO code

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BBC AM radio stations

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UK CB radio

27 MHz band: 27-60125 to 27-99125 MHz.
40 channels at 10 kHz spacing.
Max. e.r.p. 2W; max. transmitter output 4W.
Aerial: single rod or wire, l-5m overall length, base loaded. If mounted higher than 7m, transmitter output to be reduced at least lOdB.
Modulation: F.M. only, deviation ± 2-5 kHz max.
934 MHz band: 934 025 to 934-975 MHz.
20 channels at 50kHz (may be reduced to 25 kHz later). If synthesizer used spacing may be 25 kHz on precise channel frequencies specified.
Max. e.r.p. 25 W; max. transmitter output 8W; if aerial integral, max. e.r.p. 3 W.
Aerial: may have up to four elements, none exceeding 17cm. If mounted higher than 10m, transmitter output to be reduced at least lOdB.
Modulation: FM only, deviation ± 5 0kHz max.
Spurious emissions: For both bands, not exceeding 0·25ìë¥, except for specified frequency bands where the limit is 50nW.
For full specifications see publication MPT 1320 (27 MHz) and MPT 1321 (934 MHz) from HMSO.

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