Promax GV-698, Instruction Manual

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By means of the POLARITY selector [39] its polarity (positive or negative) may
be inverted in order to adapt it to the requirements of the monitor examined.
5.4 Trigger oscilloscope
The trigger output for the oscilloscope is situated on the rear panel, through the
TRIG. SCOPE connector [31].
At this output horizontal synchronisms are mixed with vertical ones of a different
amplitude. It enables a perfectly synchronized TV picture to be obtained on an
oscilloscope, independently of the amplitudes of the observed signals and thus can be
used to analyze the different circuits of a television set. This output should therefore
be connected to the external synchronism input of the oscilloscope. If the oscilloscope
has an automatic TV filter connected to the time base switch (like all PROMAX
models), it is possible to pass from the horizontal frequency to the vertical without
losing the synchronism.
5.5 R-G-B outputs
The R-G-B outputs are situated on the rear panel, through three BNC sockets
[32], [33] and [34], respectively.
By means of the selector SYNC.G [37] it is possible to insert synchronisms in
the G output.
These signals serve for the testing of colour monitors with analogous R, G, B
inputs, special effects equipment, mixer desks, etc.
NOTE: these outputs cannot be used in "ANTI-PAL" chart analysis, since it is
a natural characteristic of this signal that it affects the colour subcarrier.
5.6 LF sound input
This is via the DIN41524 LF MODULATION socket [40] situated on the rear
panel.
External audio signal inputs which may be used to modulate TV signal sound
carriers.
Figure 13.- LF sound input socket.
05/96 GV-698