Remote Control Interface - Orban OPTIMOD-FM 5500 Operation Manual

1-10
INTRODUCTION

Remote Control Interface

V p-p to produce 10% injection). Thus both inputs accommodate subcarrier genera-
tors with output levels as low as 100 mV p-p.
The correct peak level of the stereo program applied to the stereo encoder some-
times depends on the number of subcarriers in use. Some regulatory authorities re-
quire that total baseband peak modulation be maintained within specified limits.
The 5500's remote control feature allows you to reduce the stereo main level by
connecting an on/off signal from your subcarrier generator (See page 2-7). You de-
fine the amount of reduction in percent using the procedure in step 21 on page 2-
21. See page 2-42 for information on programming the remote control.
A jumper (J6) on the circuit board can reconfigure the SCA 2 input to provide the
stereo pilot tone only, which can provide a pilot reference for an RDS subcarrier gen-
erator.
The Remote Control Interface is a set of eight optically-isolated GPI inputs on a DB-
25 connector, which can be activated by 5-12V DC. They can control various func-
tions of the 5500:

Recall any Factory Preset, User Preset, Test Mode state (Bypass or Tone), or exit
from a Test Mode to the previous processing preset.

Switch the stereo encoder to stereo, mono from left, mono from right, or mono
from sum audio input. This also determines the feed to the entire processing
chain so that facilities that do not use the 5500's stereo encoder can change ste-
reo/mono mode and select the source when in mono mode.

Switch the 5500 to use either the analog input or the digital input.

Mute any output configured to emit the low-delay monitor signal.

Independently activate and defeat the diversity delay applied to the analog,
digital, and composite outputs.

Reduce the stereo main and subchannel modulation to compensate for transmit-
ter overshoot and subcarrier inputs (SCAs).
The remote control of overshoot compensation and SCA modulation (see
page 2-42) is not latching. You must supply a continuous current to the
programmed remote input to hold the gain at its compensated level. Use
the status outputs of your transmitter and/or SCA generators to provide
the switching signal so the compensation will automatically follow the
transmitter and/or subcarrier generator on the air.

Reset the 5500's internal clock to the nearest hour or to midnight.
The tally outputs can be programmed to indicate the following:

Input: Analog: Indicates that the 5500 is processing audio from its analog input.
ORBAN MODEL 5500