Burst Electronics SG-8 - Manual (Page 4)

amplitude is set to a trigger point of –20 IRE or –6
dB. This, most strict setting, will only pass
program video with near RS-170A quality. If you
would like to accept less than perfect video, such
as a VCR in Pause mode or Non-interlaced
video, then follo w the table listed below titled DIP
Switch Function.
The composite sync tip trigger threshold may be
adjusted from the factory preset of –20 IRE (-6
dB). To facilitate this adjustment, you will need a
small non-conductive screwdriver, a stable
source of video, a waveform monitor, and an
attenuator. Remove the printed circuit board from
it’s case. Input your stable source of video into
the attenuator and from the attenuator to the
video input of the SG-8. Run the video output of
the SG-8 to your waveform monitor and terminate
the monitor’s loop-out. Apply power to the SG-8.
Change DIP switch SW1-#1 to Closed. Use the
attenuator to reduce the amplitude of the
incoming video signal to the your desired trigger
level. Adjust R5 fully clockwise. Flip DIP switch
SW1-#1 to Open. Now, adjust R5 Counter
Clockwise until the SG-8 switches to it’s internal
SMPTE Bar generator (you will hear a relay
click). Remove -1 dB of attenuation, this should
be detected by the SG-8 as good video and
switch back to your stable video source. If it
doesn’t, slowly adjust R5 clockwise until your
stable video source triggers the SG-8. Confirm
that the difference of 1 dB is enough to trigger the
SG-8. Replace the SG-8 main/piggy back board
SG-8 Loss of Signal, Audio/Video, ID Inserter 4