Tektronix 7844, Инструкция по эксплуатации

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Raster Display
A raster-type display can be used to effectively increase the
apparent sweep length. For this type of display, the trace
is deflected both vertically and horizontally by sawtooth sig­
nals. One way of accomplishing this is by insta l l i ng a 78-
series time-base unit i n one of the horizontal compartments,
and a dual-trace 7 A-series amplifier unit in one of the verti­
cal compartments. A sawtooth signal must be externany
connected to one of the dual-trace amplifier inputs. Nor­
mally
I
the vertical unit should be swept slower than the
horizontal unit; the number of hori zontal traces in the ras­
ter depends upon the ratio of the two sweep rates. I nfor­
mation can be displayed on the raster using different met·
hods. To display information, a signal connected to the
unused input of the dual-trace amplifier unit can be added
to the vertical deflection. Using this method, the vertical
signal amplitude on the crt should not exceed the distance
between the horizontal l ines of the raster. Another method
of displaying information on the raster is to use the Z-AXIS
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Operating Instructions-7844/R7844 Operators
input to provide intensity modulation of the raster display.
With this system, a 7B-series time-base unit can be substi­
tuted for the external sawtooth generator and the dual-trace
amplifier unit. This type of raster display could be used to
provide a television-type display. Additional information
for using the Z-AX I S feature is given under Intensity Modu­
lation.
To provjde a stable raster display, both time-base units must
be correctly triggered. I ntE)fnal triggering is not provided for
the time-base units when they are used in the vertical com­
partments (external triggering must be used). Also, blanking
is not provided for the time-base units when they are in­
sta l l ed in the vertical compartment. To blank out the re­
trace portion from the time-base unit in the vertical compart­
ment, special connection must be made from the time-base
unit to the blanking network {for further information see
the time-base unit instruction manual } . ,
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