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FM-531HD / May 2013
F M - 5 3 1 H D G U R U G U I
Pilot Injection
The Pilot Injection control adjusts
the 19kHz stereo pilot level and is
adjustable from 0 (Off, to cause the
station transmit in Mono) to 20% of
the main composite signal amplitude,
in 0.1% steps.
Emphasis
This control sets the desired pre‑
emphasis curve to apply, 50 or 75 mi‑
croseconds, depending on the part of
the world where the FM‑531HD is being used. The pre‑emphasis may also be switched
off (FLAT) for testing or other purposes.
SCA-1 and SCA-2 Inputs
Input signals such as SCA and RDS applied to the SCA connectors are digitized
at 192kHz. Prior to being digitized the signals are high pass filtered to reduce hum
and then low-pass filtered at 94kHz. This control can be set to OFF or to levels from
‑79.95dB to +10.0dB in 0.05dB steps.
TX-1 and TX-2 Outputs
These controls adjust the output amplitude of the signals appearing at the rear
panel BNC and XLR connectors when the Output Mode is set to MPX in the Output
Configuration
screen. The TX‑1 and TX‑2 controls also adjust the modulation levels
of the Baseband192 output. Currently only the TX‑1 signal is supported by transmit‑
ter manufacturers.
These controls can be set from ‑79.95dB to +6.00dB in 0.05dB steps. Note that the
audio levels at the balanced XLR connectors are always 6dB higher than the levels at
the unbalanced BNC connectors.
There is a 0.5dB resolution available around the control’s zero setting to allow small
adjustments in actual MPX Power to compensate for unusual processing settings and how
they affect MPX Power.
IMPORTANT!
The MPX Power Controller’s sole purpose is to reduce loudness and program density.
If you are not required to use the BS412 Controller it should be left in the OFF position
because turning it on can cause up to a 5dB loudness loss when the control is set to its
“0dB” position. If your station is not required to comply with a Multiplex Power standard
where it is licensed to operate the BS412 control should remain in its OFF position!
Summary of Contents for FM-531 HD
Page 2: ...Technical Manual Wheatstone Corporation May 2013 FM HD Digital Audio Processor FM 531hd...
Page 122: ...page A 2 FM 531HD May 2013 A P P E N D I C E S Appendix A General Specifications A 3 Contents...
Page 128: ...page A 8 FM 531HD May 2013 A P P E N D I C E S Appendix B FM 531HD GPI Interface A 9 Contents...
