Crestron electronic QUICK MEDIA DISTRIBUTION CENTER QM-MD4X2 - Manual (Page 15)

Crestron QM-MD4x2 QuickMedia Distribution System
CRESCAT-QM Cable
NOTE: Do not untwist the two wires in a single pair for more than 1/3-1/2” (0.84 –
1.27 cm) when making a connection. The twists are critical to canceling out
interference between the wires.
The QM transport mechanism (receiver) uses frequency compensation on each
twisted pair video input to maintain high resolutions (1600 x 1200) with CRESCAT-
QM cable (which contains both Cresnet and CAT5E wiring) and most good quality
CAT5E and CAT6 cables (where skew rating is ≤ 15 ns / 100 meters). The total
accumulated length of the cable determines the actual skew. For example, when
connecting the QM-WMC to a QM-MD4x2 and then to the QM-RMCRX, the total
accumulated skew must not exceed 15 ns and the total cable length cannot exceed
300 feet.
NOTE: The length of CAT5/5E/6 cable that can be used can vary. However, the
total skew must be ≤ 15 ns.
NOTE: Longer lengths of cable may experience eventual loss of bandwidth when
viewing higher resolution sources.
The following diagram illustrates how composite, S-video, and RGB video signals
are transmitted over the CAT5E wire.
Quick Media Video Signals on CAT5E
NOTE: When transmitting S-video or composite video, luminance uses the green
video pathway, chrominance uses the red video pathway, and composite uses the
blue video pathway.
Operations Guide - DOC. 6278 QuickMedia Distribution System: QM-MD4x2 • 11