Subcarrier Phase - DEVA Broadcast SmartGen Mini Maintenance And Operation Instruction Manual

SUBCARRIER PHASE

In the interest of maintaining optimum carrier modulation by the program signal, the 57kHz
RDS subcarrier should be in quadrature with the 19kHz stereo pilot. Both in-phase and quadrature
relationships are shown here in figures below, respectively. Note that a quadrature relationship
yields a slightly lower peak level, which allows the greatest carrier modulation by the program
audio signal.
Subcarrier in-Phase
The SmartGen Mini has the ability to smoothly adjust the phase of the generated RDS signal to
the PILOT tone. Although some stereo generators supply a pilot-sync reference for RDS (usually a
TTL-level squarewave), this reference may or may not be in exact phase with the actual stereo pilot
component of the composite/MPX signal. For this reason we recommend using the composite/
MPX signal for synchronization. In the sidechain mode, the SmartGen Mini simply bridges the
output of the stereo generator and does not load or otherwise compromise the composite/MPX
signal.
65 Aleksandar Stamboliyski Str., 8000 Bourgas, Bulgaria
Tel: +359 56 820027, Fax: +359 56 836700
E-mail: office@devabroadcast.com ,Web: www.devabroadcast.com
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Subcarrier in Quadrature