19
Subject to change without notice
None of these will appear in the readout in undelayed time
base operation.
When
”SEA”
,
”DEL”
or
”DTR”
mode is effective, pressing
and holding the button switches over to undelayed time
base.
Provided that neither
”SEA”
nor
”DEL”
resp.
”DTR”
are
active, the following description assumes that:
1.X-MAG. x10 is switched off,
2.the trace starts on the left vertical graticule line and
3.the part of signal to be expanded must be displayed
within the (horizontal) range 2 up to 6 divisions after
trace start position.
SEA
In
SEA. (SEARCH)
mode, the hold off time is automatically
set to minimum and for the first few divisions the trace
is blanked. The trace will then be unblanked. The point at
which the trace starts can be varied with DEL.POS (fine
adjustment) from about 2 to 6 divisions. The blanked
section serves as a guide to the delay time. The delay time
is based on the current time deflection coefficient setting
and can also be coarsely set with the TIME/DIV control
(range: 20ms to 100ns).
DEL
Pressing the button briefly switches over from
”SEA”
to
”DEL”
(DELAY) mode. Now the trace starts at the left
vertical graticule line, beginning with that part of the
signal that was previously unblanked first when
”SEA”
was active. From that position, the signal display can be
expanded in the X-direction by rotating the
TIME/DIV
control clockwise and thus decreasing the time deflection
coefficient. If a part of the signal of interest goes beyond
the right edge, it can be brought within the screen and
made visible by
DEL.POS
knob. Increasing the time
deflection coefficient beyond that used in the
”SEA”
(SEARCH)
mode is not possible.
In the untriggered
”DEL” (DELAY)
mode, a trigger event
does not start the trace at once but only starts the delay
time. After the delay time has elapsed the trace is started.
DTR
In triggered
DELAY
mode
(DTR)
, to start the sweep, a
signal suitable for triggering must appear after the delay
time. The trace will be started if the instrument settings
(e.g. LEVEL setting) enable a triggering. See DEL.TRIG.
- VAR. (30).
(30) DEL.TRIG. - VAR.
- Pushbutton with two functions
The pushbutton is operative only in analog mode.
In the case of untriggered
”DEL” (DELAY)
mode
(29)
,
briefly pressing the button switches over to
”DTR”
(triggered DELAY mode). Thereby, the previously active
settings,
Automatic/normal
triggering
(15)
, trigger
LEVEL (17)
,
trigger slope (15)
and
trigger coupling
(26)
will be stored.
The instrument will be automatically switched to normal
triggering
(NM)
and
DC
trigger coupling in
”DTR”
mode.
Subsequently the trigger
LEVEL
setting and the trigger
slope should be so adjusted that the signal for delayed
trigger can trigger the time base. Without triggering the
screen will remain blank.
Briefly pressing the button again switches back to
(untriggered)
DEL.
operation.
VAR.
Pressing and holding the pushbutton changes the function
of the
TIME/DIV.
knob.
The
TIME/DIV.
knob
(28)
can function as a time deflection
coefficient switch (1-2-5 sequence) or as a time vernier
(fine adjustment). The current function is indicated by the
VAR-LED.
The
TIME/DIV.
knob functions as a vernier
when the VAR-LED is switched on, but the time base
setting remains calibrated until the (vernier) knob is
operated. The readout now indicates
”T>...”
instead of
”T:...”.
Rotating further anticlockwise increases the time
deflection coefficient (uncalibrated) until the maximum is
reached indicated by a beep. Rotating the knob clockwise
has the opposite effect. Now, the vernier is again in the
calibrated position and the symbol
” >”
will be replaced
by symbol
” :”
.
The function of the knob can be switched back to normal
(calibrated) time base, pressing and holding the button.
Underneath the front panel sector described above, the
BNC sockets and four pushbuttons are located.
(31) INPUT CH I - (HOR. INP. (X))
- BNC socket.
This BNC socket is the signal input for channel I
(INPUT
CH I)
. In XY mode, signals at this input are used for the X-
deflection. The outer (ground) connection is galvanically
connected to the instrument ground and consequently to
the safety earth contact of the line/mains plug.
(32) AC / DC
- Pushbutton with two functions.
Input coupling:
Briefly pressing this pushbutton switches over from
AC
(
~
symbol) to
DC
(
=
symbol) input coupling and vice versa,
if the input is not switched to
GD (33)
. The
AC/DC
setting
is displayed in the readout with the deflection coefficient.
Probe factor:
Pressing and holding the pushbutton selects the indicated
deflection coefficient of channel I displayed in the readout,
between 1:1 and 10:1. In condition 10:1 the probe factor
is thus indicated by a probe symbol displayed by the
readout in front the channel information (e.g.
“probe
symbol”
,
Y1...
). In the case of cursor voltage measu-
rement, the probe factor is automatically included.
Controls and readout
