Operating Instructions—T y p e 3 2 4
tical center; selects negative (—)
slope triggering level when the
knob's indicator spot is to the right
of vertical center. The indicator
spot and the plus and minus wave
form slopes (which appear along
side the TR IG G E R knob) indicate
the approximate point on the wave
form at which triggering occurs.
When the control is at the counter
clockwise (+ AU TO ) or clockwise
(— A U TO ) limit, a baseline is auto
matically provided during the ab
sence of triggering signals. Input sig
nals whose frequencies are higher
than that of the automatic base line
generator provide a stable triggered
display.
Top Panel
FOCUS
IN T E N S IT Y
Left Side Panel
Trig/Horiz Coup-
Four position level switch. Selects
ling Switch
the source and type of triggering.
Also selects E X T H O R IZ INPUT
coupling mode.
E X T T R IG OR
H O R IZ
A TTE N
I N T T R IG
Selects Internal AC triggering sig-
ACLF REJ
nal; the triggering circuit is de
sensitized to signals below about 15
kHz.
AC
Selects Internal AC triggering sig
nal.
INPUT
EXT T R IG
OR H O R IZ
AC
DC
Refers to External Horizontal input
coupling when T IM E /D IV is in
E X T H O R IZ position; refers to Ex
ternal Trigger coupling mode in all
o th e r p o s itio n s of T IM E /D IV
switch.
Selects external AC triggering sig
nal.
Provides direct coupling of an ex
ternal triggering signal. Autom ati
cally reverts to AC coupling during
A U TO trigger operation.
E X T BLANK
V E R T INPUT
Thumbwheel accessible through top
panel. Adjusts CRT electron beam
for optimum display sharpness.
Thumbwheel accessible through top
panel. Controls the brightness of
the CRT display.
IMPORTANT
Battery operating time varies
inversely with CRT trace in
tensity. Use the minimum
brightness necessary for good
viewing.
Two position slide switch. When in
10X position it attenuates the E X T
T R IG OR H O R IZ IN PU T signal by
a factor of 10.
BNC connector with 62 pF input
capacitance. Has 1
input resist
ance whenever the Trig/Horiz coup
ling switch is at DC or when the
E X T T R IG OR H O R IZ A TTE N
switch is at 10X. Maximum allow
able input is 500 V DC + peak AC.
Banana jack; input is DC coupled to
the unblanking circuits. Positive sig
nals between 5 and 20 volts cause
blanking of CRT trace. 150 V DC +
peak AC maximum allowable input
signal.
BNC connector with 1 M fi and 47
pF input impedance. 500 V DC +
peak AC maximum allowable input.
IMPORTANT
NOTE
The T rig /H o riz Coupling
switch must be in an EXT
TRIG OR HO RIZ position
when E X T H O R IZ operation
is selected by the TIM E /D IV
switch. Leaving it in either of
the I N T TRIG positions when
E X T HO RIZ operation is se
lected applies the vertical sig
nal to both the vertical and
horizontal axis.
Battery operating time varies
inversely with input signal
frequency and the display
amplitude.
CAL O U T
Banana jack which makes the verti
cal amplifier 0.5 volt square wave
signal available for monitoring or
external use, such as probe calibra
tion. Has approximately
10 kft
source impedance. External load
will decrease its output in propor
tion to the load.
2-7