Promax GV-698, Инструкция по эксплуатации

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Group G.-
Focus control, geometry and matt supply.
- G1 100% white
Verification of the limiter circuit for the beam current, modulation adjustment
on videotapes, measurements of the signal/noise ratio.
- G2 black
Clamping check, measurements of the signal/noise ratio, adjustment of the
level of black.
- G3 50 Hz rectangular
Clamping circuits check.
- G4 MAT
Very High Tension source control.
Group H.
- H1 Cross and rectangle
Aspect, geometry and centrality ratio.
- H2 Framed grid
Centered adjustment of the picture and overscanning.
- H3 Grill
Static and dynamic convergence adjustment, interline check.
- H4 Points
Picture suitable for the adjustment of the focus voltage.
4.3 Function buttons which modify the composite video signal
Their effect may be observed at the outputs at which a composite video signal
is present (VIDEO output [24], EURO–AV Euroconnector [36] pin 19 and Y–C
output [38], and in the RF modulated signal (RF connector [11]).
- BURST OFF [22]: press this button to suppress the burst of the composite
video signal and enable the correct operation of the colour killer in the
receivers to be checked. In a correctly adjusted TV receiver no colour
appears on the screen if the burst is cancelled. Anomalous colorations may
be due to high gain in the amplifiers and some deficiency is likely to have
appeared at this stage.
When the SECAM system is selected, pressing this button eliminates the
line identification signal.
- OFF [21] (Chrominance): press this button to disable the chrominance.
It enables suppression of the colour subcarrier in the video signal in order
to analyze the luminance of the colour charts.
- CIRC. [20] (Electronic circle): press this button to activate the circle which
may be inserted in any chart and is particularly useful in geometric
adjustments.
NOTE: the insertion of the circle in the multiburst chart is not perfect, since
this signal does not pass through circuits which would limit its bandwidth. As
the circle in this chart does not provide any information of interest, it is
preferable not to insert it during definition studies.
05/96 GV-698