Dmpx; Μmpx Composite Over Ip (Optional); Wordclock/10 Mhz Sync Reference - Orban OPTIMOD 5750 Operating Manual

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Installation
As shipped from the factory, the second SCA connector emits a stereo pilot tone
reference for RDS or RBDS subcarrier generators. If you wish to reconfigure it to accept an SCA signal,
move the link on jumper J6 (on the Composite/SCA daughter-
board) from pins 3 and 4 to pins 1 and 2.
•
To access J6, remove the 5750's top cover according to the instructions in step 1 on page 4-2. The schematic
showing J6 is on page XXX.
Connect your subcarrier generator(s) to the 5750's subcarrier input(s) with coaxial cable terminated with BNC
connectors.
•
The subcarrier inputs have greater than 600 load impedance and are unbalanced. The sensitivity of both inputs
is user-adjustable from <100 mV p-p to >10 V p-p to produce 10% injection with respect to 100% modulation =
4V p-p at the 5750's composite outputs. (The factory setting is 4 V p-p to produce 10% injection.)
•
VR1 and VR2 on the Composite/SCA daughterboard set the sensitivity of SCA1 IN and SCA2 IN respectively and
are accessible on the rear panel, You can use the 19 kHz reference control in the setup to determine whether
the 19 kHz pilot reference output will be in-phase (0 DEG) with the pilot tone present in the composite output
or will lead it by 90 degrees (90 DEG). 0 DEG is correct for most installations. Use 90 DEG only if your RDS/RBDS
generator's 19 kHz reference input specifically requires this phase relationship.

DMPX

When Digital Output 2 is set for DMPX, the digital output XLR jack on the rear of the 5750 carries an AES over MPX
digital composite signal that is compatible with exciters designed to ingest a digital composite signal. The benefits
of using the DMPX signal is the elimination of the D-A and A-D converters found in the analog composite output.
WARNING: You should check with your exciter manufacturer to make sure your equipment has the capability to
ingest the DMPX standard before using this option. Interfacing the 5750 with DMPX into a non-compatible exciter
µMPX Composite over IP (optional)
The optional µMPX mode of composite transport is a specialized codec that can carry the composite payload
(including RDS) over an internet connection of at least 320kbps. This is another option to placing the 5750 at the
studio. While revolutionary in theory, there are some tradeoffs with µMPX such as an elevated noise floor. In most
cases, this won't be an issue as the noise floor remains below acceptable standards.

Wordclock/10 MHz Sync Reference

The sync reference input accepts a 1x 5V p-p squarewave wordclock signal or a10 MHz sinewave or squarewave
signal, 0.5 to 5 V peak. A menu item allows you to synchronize the output sample frequency to the frequency present
at the sync. The connector is a female BNC with the shell grounded to chassis.
will cause unwanted results.