Tektronix 7834

Operating Instructions-7834
Readout Operation With Storage . Each of the storage
modes modify the operation of the Readout System,
to
some extent . With
the READOUT
GATED or FREE RUN
switch set to FREE RUN the Readout System operates as
follows :
BISTABLE AND VAR PERSIST
.
In the
BISTABLE
and VAR PERSIST positions, of the
Storage
Mode switch,
the readout display is turned off during the storage erase
cycle ; otherwise, the Readout System operates as previously
described under READOUT MODES .
FAST BISTABLE AND
FAST VAR PERSIST .
In
the
FAST BISTABLE and FAST VAR PERSIST positions,
of
the storage mode switch, the Readout System turns off at
the beginning of an erase cycle or when the single-sweep
time-base mode is reset and remains off until the end of the
storage transfer cycle . In addition, the Readout System is
held off whenever the MULTI TRACE DLY control is in
operation (out of its detent position) and the displayed
time-base unit is in a repetitive sweep mode .
With the READOUT GATED or FREE RUN switch set to
GATED the
Readout System operates as follows :
BISTABLE . In the BISTABLE storage mode, the read-
out display
runs
continuously (as in the free run mode) ;
however, the
readout system turns off when the storage
erase cycle begins and remains off until the end of the first
displayed sweep .
VAR PERSIST . In the VAR PERSIST storage mode
one complete frame of readout is displayed after the
displayed time-base unit completes each sweep ; however,
there is no readout display during
a storage erase cycle .
FAST BISTABLE . In the FAST BISTABLE storage
mode the readout display runs continuously (as in the Free
Run mode) ; however, the
readout system turns off at the
beginning of each erase cycle
or when the single sweep
time-base mode is reset and remains
off until the end of the
storage transfer cycle . In addition,
the readout system is
held off whenever the MULTI TRACE DLY control is in
operation (out of its detent position) and the displayed
time-base unit is in a repetitive sweep mode .
FAST
VAR
PERSIST
.
In the FAST VAR PERSIST
storage
mode,
one complete frame of readout is displayed
after the completion
of the storage transfer cycle . However,
there is
no
readout during
a storage erase cycle and there is
no readout when
the MULTI TRACE DLY control is out of
detent
position and the displayed time-base unit is in a
repetitive
sweep mode .
2- 1 4
STORAGE SAVE READOUT MODES .
When the
storage system enters the SAVE mode, the operation of
the
readout system changes from that previously described
under
FREE
RUN and GATED READOUT
modes for the
BISTABLE, VAR PERSIST, FAST BISTABLE, and FAST
VAR PERSIST positions of
the
Storage mode switch
.
(Refer to the SAVE mode discussion, in this manual, for
information on the SAVE mode operation .)
Save With Free Run Readout . With the READOUT
GATED or FREE RUN switch set to
FREE
RUN and the
Storage mode switch set to any one of the storage modes,
the
readout system turns off approximately 1 second after
the storage system enters the SAVE mode .
Save With Gated Readout . With the READOUT
GATED or FREE RUN switch set to GATED and the
Storage
mode
switch set to BISTABLE or
FAST
BISTABLE, the
readout is displayed
for approximately
1 second after the storage system enters the SAVE mode,
then it turns off ; with the READOUT mode switch set to
GATED and the Storage mode switch set to VAR PERSIST,
1 complete frame of readout is displayed at the end of the
displayed sweep ; with the READOUT mode switch set to
GATED and the Storage mode switch set to FAST VAR
PERSIST, 1 frame of readout is displayed at the end of the
storage transfer cycle, or whenever the storage system
enters the save mode and the MULTI TRACE IDLY control
is out of its detent position .
Reduced Scan Mode
The Reduced Scan mode increases the stored writing speed
(in centimeters/microsecond) . The calibrated graticule
division size changes from
0 .9
centimeters in the Full
Scan
mode to 0 .45 centimeters in the Reduced Scan mode .
Calibrated measurements are confined to the inner half-size
8 x 10 graticule area . The operation of the instrument
controls do not change from their operation in the Full
Scan mode .
Storage Display
The 7834 Storage
Oscilloscope has four selectable storage
modes . Listed in order of increasing writing
speed, they are :
BISTABLE, VARIABLE PERSISTENCE, FAST
BISTABLE, and FAST VARIABLE PERSISTENCE . In
each mode the viewed image is stored on the storage target
located in the front of the crt .
In
the BISTABLE mode the luminance of any point on the
storage target will take on one of two discrete
levels,
either
written or unwritten . In this mode, only the A or B
INTENSITY controls affect the stored writing speed ;
writing
speed is quite low but the stored view time is
indefinitely long .