Hall Research HR-731-S - Manual (Page 6)

4
Model HR-731-S
4.0 Theory of Operation
The Sender HR-731-S provides an HDMI input with audio embedded in the
video on the same connector.
The video data is transmitted on only one multi-mode fiber. A multi-mode fiber
(rather than single mode) is required since the TMDS video data is transmitted
over a range of optical wavelengths to reduce bandwidth requirement at any
particular wavelength. The TMDS signals use LED lasers to drive the cable. For
safety reasons, these lasers are not turned on if no cable is plugged in at both the
Sender and Receiver.
Additional (non-video) hand-shake signals are also seamlessly connected
between the source and the sink device. These include:
• DDC Channel (SDAT and SCLK) for EDID and HDCP
• Hot Plug Detect (to detect remote monitor connection)
• Source Active +5vDDC (to indicate to sink there is a source)
In addition, the fiber-optic link provides a general purpose bi-directional data
lane that can be designated by the user to be either RS-232 pass-through or CEC
as defined by HDMI specifications. By default the HR-731 uses the data lane for
RS-232 control. Note that in CEC mode, the RS-232 connector on the Remote
does not serve any function but the RS-232 port on the Sender can still be used
for configuration changes.
5.0 Installation
HR-731 kit is comprised of a HR-731-S sender and a HR-733-R receiver.
The following block diagram depects an HR-733-S as a sender. The HR-731-S
only has one video input. The receiver is the same for both senders.
Figure 2 – Block Diagram (HR-731-S only has one HDMI video input)