Extron Electronics VN-QUANTUM User Guide - Manual (Page 61)

VN-QUANTUM User Guide Section 3: Functional Overview
I455GB issue 8 Page 61
Auto-detection of Source Types
Full auto-detection is provided on each input, allowing a wide range of standard source types to be
connected without the need for any further configuration. However, VN-COMMANDER provides the
means to create fixed or custom input modes.
NOTE: PAL 60 format is not supported. PAL 60 is commonly output by European VCRs when playing
back an NTSC tape.
Automatic gain control (AGC) ensures optimum source display with signals as low as 20% of normal
amplitude.
NOTE: Due to the dynamic nature of AGC an identical source fed to different inputs may not display
with identical results.
Timebase Correction (Frame Synchronization)
Incoming sources are digitized and then synchronized internally to a specified clock signal derived
from either:
The refresh rate of the display outputs; or
The refresh rate of a designated video source input.
This ensures clean switching between sources without the need for any external source
synchronization.
NOTE: If frame-accurate synchronization is required between some or all sources, these will need to
be synchronized externally.
Macrovision-encoded Sources
Many pre-recorded videos and DVD’s are copy-protected by a system called Macrovision®. It works
by inserting variable intensity signals into the non-visible region of the source signal. These ‘false’
signals ‘confuse’ the AGC circuit of conventional recording devices, preventing the source from being
copied satisfactorily.
Typically more than 90% of Macrovision-encoded sources can be viewed successfully. However,
certain sources may suffer some visual disturbance or fail to achieve full signal lock.