R.V.R. Electronica discovery, Руководство пользователя

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DISCOVERY
7 / 44 User Manual Rev. 2.1 - 27/11/03
4. General Description
The Discovery control unit is an appliance that allows providing for audio black
outs.
If positioned in series with the transmitting appliance, it allows automatically
selecting the alternate audio in case of failures or damages to the main signal.
This appliance is extremely useful for those systems where one or more satellite
receivers combined with an already existing terrestrial backbone are used. The
reception by satellite offers excellent technical advantages, but is vulnerable during
summer storms. When these meteorological conditions occur, the high flow of rain
screens the radio carrier coming from the satellite, making the audio signal
unavailable, and the blackout time changes from five to twenty minutes on average.
Discovery allows automatically changing over, according to the priorities entered,
up to four audio channels, two of which are composite (MPX) and two stereo.
The automatism is based on the detection of the selected channel functionality.
Operation times for the several detection modes and reset times may be
programmed. In case of analog detection, operation thresholds may be programmed
as well.
All operative parameters of Discovery may be downloaded/loaded by PC or
changed by display and keyboard installed on the appliance front panel. It is possible
to lock the operative configuration of Discovery by means of the software from
PC; in such situation, data may only be examined, but not changed.
The monitoring circuit of Discovery was designed with the always-present "Fault
tolerance" concept; therefore, if the network fuse breaks down, the channel defined
as primary channel does not cuts off. Other solutions have been adopted and will
be described further on, in this manual.