Technalogix TXF-500, Руководство по эксплуатации

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Frequency: With the exciter being agile, the user can change frequency
from the front touch screen. The step size is 100 kHz. At the
lower and upper frequency limits of the FM band, the
frequency will wrap back around.
Pre-Emphasis:
Pre-emphasis adds a boost to high frequencies in the FM
signal to increase the signal above the noise floor. The FM
signal then is de-emphasized at the radio receiver end.
Users can change the amount of pre-emphasis to suit their
location and receivers. A lower pre-emphasis, say 50 us
versus 75 us, is a lighter boost, but also increases high
frequency headroom. Setting the pre-emphasis to 0 us turn
off the pre-emphasis. Standard North American pre-
emphasis is set to 75 us on the transmitter side, while most
of the rest of the world incorporates 50 us.