29
Subject to change without notice
Short instruction for HM304
Switching on and initial setting
Case, chassis and all measuring terminals are connected to the safety earth conductor (Safety Class I).
Connect instrument to power outlet, depress red
POWER
button. LED‘s indicating operating condition.
Instrument is set as it was before switching off.
Adjust trace intensity for medium brightness.
If no trace is visible, depress
AUTO SET
to switch to Yt mode.
Focus trace using
FOCUS
.
Vertical amplifier mode
Channel I
: If no LED lit on the
CH I VOLTS/DIV
scale, depress pushbutton
CH I.
If a LED on the
CH II
VOLTS/DIV.
is lit too, depress pushbutton
CH II
to switch it off.
Channel II
: If no LED lit on the
CH II VOLTS/DIV
scale, depress pushbutto
n CH II.
If a LED on the
CH I
VOLTS/DIV.
is lit too, depress pushbutton
CH I
to switch it off.
DUAL
(channel I and channel II): Depress the
CH I
or
CH II
pushbutton so that a LED is lit on both channel I and
II VOLT/DIV scales.
Addition (
ADD
): Depress both
CH I
and
CH II
pushbuttons simultaneously until the
ADD LED
lights.
Addition (sum): With both input signals in phase switch both
INV LED‘s
on or both off.
Addition (difference): With both input signals in phase switch only one
INV LED
on.
Addition mode can be exited by depressing both
CH I
and
CH II
pushbuttons simultaneously until the ADD LED is dark.
Triggering mode
Select trigger mode by depressing both
NORM
pushbuttons simultaneously:
NM LED
dark = automatic peak (value) triggering < 20 Hz - 100 MHz.
TRIG. LEVEL
active.
NM LED
lit = normal triggering.
TRIG. LEVEL
active.
Trigger edge direction: select with ± pushbutton. -
LED
lit = falling slope, dark = rising slope.
Internal triggering: In
CH I
and
CH II
mode automatically set and indicated by
TR I
and
TR II LED‘s
.
In
DUAL
and
ADD
mode briefly depress the
TRIG.
pushbutton for switching over.
Internal alternate triggering:
IN DUAL
mode depress and hold the
TRIG.
pushbutton until both
TR I
and
TR II
are lit.
Switch off this mode by briefly depressing the
TRIG.
pushbutton.
External triggering: Depress the
EXT
pushbutton next to the TRIG. INP. BNC socket to light the
EXT LED
.
Trigger Signal 0.3Vpp - 3Vpp at
TRIG. INP.
Return to internal triggering by depressing the
EXT.
pushbutton again (EXT LED dark).
Line triggering: Select the
~
symbol on the trigger coupling scale depressing one of the NORM pushbuttons (up / down).
Trigger coupling: Choose
AC/DC/HF/LF/TV-L/TV-F
by depressing one of the
NORM
pushbuttons.
Frequency ranges:
AC
10Hz - 100MHz;
DC
0Hz - 100MHz;
HF
1.5kHz - 100MHz;
LF
0Hz - 1.5 kHz.
TV-L to trigger on line sync. pulses;
TV-F
to trigger on separated frame sync. pulses. Select
± (SLOPE)
for the
leading slope. Sync pulse above picture content =
+
( - LED dark ), below =
-
( - LED lit ).
Pay attention to trigger indicator:
LED
above
TRIG.
Measurements
Apply test signal(s) to the vertical input connectors of
CH I
and/or
CH II
.
Before use, compensate attenuator probe with built-in square wave generator
CAL
.
Depress
AUTO SET
for automatic instrument set up or:
Select
AC
or
DC
(LED lit) input coupling (GD LED dark).
Adjust signal to desired display height with
< >
arrow pushbutton(s) in
VOLTS/DIV.
sector.
Amplitude measurement with Y fine control (
VAR. 2.5:1
) at right stop.
Adjust signal to desired number of displayed periods with
< >
arrow pushbutton(s) in
TIME/DIV.
sector.
Time measurement with time fine control (
VAR. 2.5:1
) at right stop.
Time expansion with
x10 LED
lit.
Set trigger point with
TRIG. LEVEL
knob in automatic peak (value) and normal (
NM LED
lit) triggering.
Select automatic peak (value) or normal triggering by depressing both NORM pushbuttons simultaneously.
Improve complex or aperiodic signal stability with longer
HOLD OFF-
time or in
DELAY
mode (
DEL
or DTR).
For the expansion of signal portions, use delay (
DEL
) or after delay trigger mode (
DTR
) with reduced
time coefficient (
TIME/DIV
).
Normal undelayed mode = no
DELAY LED (SEA/DEL/DTR)
lights.
Depress
DELAY
pushbutton once (SEA - search - LED lights) and adjust the timebase start position using
DEL. POS.
knob and
TIME/DIV < >
pushbutton(s).
Brief depress
DELAY
pushbutton to switch over to delay mode (
DEL
lights). Now the timebase starts (DEL lit)
with the selected start point and the trace length has full length. For start point and expansion rate corrections use
DEL. POS.
and
TIME/DIV
settings.
Depressing the
DELAY
pushbutton once again switches over to triggered delay mode (
DTR
lights) and
automatically to
DC
trigger coupling (
DC LED
on
TRIG
scale lights) and normal triggering (
NM LED
lights).
± (SLOPE)
and
TRIG. LEVEL
are active and set in their priviously used settings.
Depress the
DELAY
pushbutton again to switch to normal mode. Then all LED‘s on the
DELAY
scale are dark.
SEA
and
DEL
can be exited without stepping through the modes by depressing and holding the
DELAY
pushbutton until all LED‘s are dark.
Component tester mode
Depress
COMP. TESTER
pushbutton.
COMP. TESTER
mode is active if all LED‘s are dark (exception X
MAG. x10
).
In-circuit-test: Circuit under test must be disconnected from battery or power (pull out power plug), signals and
ground (earth). Remove all signal connections to the instrument (cable, probe), then start testing.
