Tektronix 485 User Manual

Operating Information—485/R485 Service
SCALE ILLUM
Controls illumination of internal
Control
CRT graticule.
BEAM FINDER
Compresses trace within graticule
Pushbutton area, regardless of position control VARIABLE volts/div
settings or amplitude of signal Control, CH 1 and
applied.
CH 2
BW LIMIT Limits to approximately 20 MHz
Pushbutton the bandwidth of the vertical ampli
fier system and of the INTernal
TRIGger signal.
GAIN Adjustment,
20 MHz Indicator Lights when bandwidth of vertical
CH 1 and CH 2
amplifier is being limited.
A EXT TRIG
VERT MODE
Pushbutton Selector
Pushbutton
(momentary not on
485-1 and 485-2)
CH 1 Displays Channel 1 only.
1 MS2/50 SI Switch,
ALT Dual trace display by switching
CH 1 and CH 2
between channels at the end of A
(485-2 has RESET-
sweep.
PUSH)
CHOP
Dual trace display by switching
between channels every 0.5 ps (1
MHz chopped display).
ADD Algebraically adds CH 1 and CH 2
input signals.
RESET Indicator
X-Y
Permits X-Y operation. Displays CH
1 signal on the vertical (Y) axis and
the CH 2 signal on the horizontal
(X) axis, with a 4 MHz phase-
compensated bandwidth.
Input Selector Switch,
CH 1 and CH 2
CH 2
Displays CH 2 only.
AC
INTTRIG
Pushbutton Selector
GND
NORM
The signal being displayed is the
internal trigger source.
CH 1
Selects CH 1 as the internal trigger
source.
DC
CH 2
Selects CH 2 as the internal trigger
source.
Input CH 1 or Y
VOLTS/DIV Switch,
Selects IX calibrated deflection
Connector and CH 2
CH 1 and CH 2 factors from 5 mV/div to 5 V/div in
or X Connector
ten steps (1-2-5 sequence). Attenu
ating probe tip deflection factors
for X I0 and X I00 coded probes are
POSITION Controls,
automatically indicated by the
three readout lamps at the circum
ference of this knob. All three
lamps are off when the channel is
CH 1 and CH 2
not selected for display by the
VERT MODE selector, or when
using probe IDENTify.
Provide continuously variable
deflection factors between calibra
ted steps. Maximum deflection
facto r range is extended to
1 2.5 V /div. Push-away control
provides calibrated deflection fac
tor in the CAL IN position.
Screwdriver adjustment allows cali
bration of vertical deflection factor.
Overrides other vertical controls to
display the external signal being
used for A sweep triggering.
Illuminated push-push selection for
input impedance. Is also used to
reset 50 SI overload condition
(1 MS2/50 SI switch must be pushed
twice to return to 50 SI input
impedance). 485-2 is non-
illuminated momentary switch for
RESET only.
When maximum input power is
exceeded in the 50 SI mode causing
the overload disconnect to operate,
the RESET indicator is illuminated,
and the 1 M J2/50 SI lamp is turned
off.
Capacitively couples input signal to
vertical amplifier.
Grounds the amplifier input and
permits precharging the AC input
coupling capacitor. 50 SI termina
tion disconnected in the 50 SI
mode.
Signal is directly coupled to the
vertical amplifier.
BNC connectors for applying exter
nal signals. Included are concentric
coding rings for probes with scale
factor and identify switching.
Vertically positions the display. In
X-Y mode, CH 1 controls positions
in the Y (vertical) axis and the CH
2 control positions in the X (hori
zontal) axis.
2-2

Tektronix 485 Specifications

General

Brand	Tektronix
Model	485
Category	Test Equipment
Language	English