Burst Electronics SG-8 - Manual (Page 5)

into it’s case.
When any of the first three switches are Open,
the micro controller will test the associated input
pins for valid signals. When a switch is closed,
the test for that signal will be skipped. All enabled
tests must pass consecutively before input “A” is
considered good.
If SW1-#1 is Open, the sync tip level test is
enabled. This test detects the presence of sync
tip. The trigger point for this test can be modified
by the adjustment of R5. Burst Electronics sets
this trigger point for –20 IRE (-6 dB). If –20 IRE or
less is obtained, this test will cause the SG-8 to
switch to internal Color Bars.
If SW1-#2 is Open, the vertical sync test is
enabled. This test will detect the presence of
white noise (snow) and cause the SG-8 to switch.
If SW1-#3 is Open, the frame test is enabled.
Progressive scan video signals (VCR Blue
Screen) and VCR search/scan and pause modes
will be detected as bad video and cause the SG-8
to switch.
Detection time will increase in relation with how
many signal tests are enabled. Detect time will
substantially increase if SW1-#4 is Open. This
switch will resample the video several times, the
delay is approximately 4 seconds.
SG-8 Loss of Signal, Audio/Video, ID Inserter 5