70-centimeter band
70 -centimeter band refers to the frequency range of 400 MHz to 460 MHz. The name is derived from the approximate wavelength of this frequency range.
This frequency range is used by commercial radio, bad radio and amateur radio service ( primary use 430-440 MHz) used. In this frequency range, often hand-held radios are used. To achieve a large area with low power, the relay stations may be used.
Propagation conditions
Radio waves these (and higher ) frequencies propagate quasi- optically. This means that only a few obstacles between the transmitter and receivers can affect the connection strong. Therefore, the maximum ranges in everyday life are rarely accessible.
70 -centimeter amateur band
The European 70 -cm amateur band uses the frequency range 430-440 MHz. In other countries, the frequency range 420-450 MHz is allocated to the amateur radio. It is the lowest frequency band, is permitted in the Amateur Television. A large area of the 70 -cm band is approved for operation on amateur radio satellites, this area is kept free of the band plan for 70 cm.
Band Plan
- Relay stations
- Packet Radio
- E.g. the amateur radio and television
- Relay stations
- SSTV 433.400 MHz
- RTTY 433.300 MHz
- Digital Mobile Radio 433.450 MHz
- Relay stations
- Packet Radio
- 439.9875 MHz paging ( POCSAG )
70 - centimeter -BOS - band
This tape is often used as a microwave link of simulcast radio systems or DAU.
Other users
The range of 433.05 to 434.79 MHz is used as the ISM band (secondary use), eg for wireless thermometer, wireless switch (car key with keyless go, electric outlets, LPD and similar. ). This SRD have a maximum power of 10 mW and 69 channels and are free of charge. The range is 0.3 km ( city) up to max. 2.5 km ( open area ). This frequency range is also used by amateur radio service. Interference by the amateur service must be accepted.
The area 446.00625 to 446.09375 MHz is provided with 8 channels and a maximum power of 500 mW ( ERP) for PMR. The ranges are slightly better than LPD devices due to the higher performance with 0.5 up to 5 km in an open area. In this area even newer baby monitors work.