Tektronix 2235 User Manual

In the Χ - Υ mo
de of operation, the Channel
1 signal from

signal from
the Cho p Oscillator circuit b
lanks the crt d isplay
the Internal Trigger
circuitry passes through t he
Χ - Υ Amplifi-

while
switching b etween the vertical
channels .
e r to the Horizontal
Preamplifier . In this
operating mode, the
Channel 1 Internal
Trigger signal su p plies
the h orizontal de-
flection to the crt,
and the M iller Sweep
circuit is disabled to

The Dc
R estorer circuit applies the output
voltage of the
inhibit sweep
generation .

Ζ -Axis Amplifier
between the cathode and grid
of the crt .
High do potentials on
these elements p
rohibit d irect coupling
to the crt .
The Alternate Β Sweep
circuitry controls the
Alt and
Β Horizontal mode displays
and includes the Β M iller Sweep
Generator and Β Sweep
Logic circuitry . In addition to p
ro-

The Power
Supply p rovides the n ecessary
operating
viding the Β Sweep
sawtooth waveform, signals are
gener-

voltages for the
instrument . Operating p otentials
are ob-
ated which control the
d isplay switching b etween the Α and

tained from α
circuit composed of the Preregulator,
Inverter
Β displays .

and

Transformer,

and

Rectifiers

and

F ilters .

The
Preregulator
produces approximately +43
V do from the ac
p ower
line which is used to drive the 20
kHz Inverter stage .
The intensity levels of
both t he Α and Β Sweeps
are set

The
transformer secondary windings p rovide
various ac lev-
by the front-panel
Α and Β I NTENSITY controls .
These con-

els that are
rectified and filtered to produce
the op erating
trols, along with
signals from the Α and Β Sweep
Logic

voltages .
Α h igh-voltage multiplier
circuit produces the ac-
circuits, determine the
drive level to the Ζ -Axis
Amplifier .

celerating, focus,
and cathode potentials re q
uired by the crt .
The Ζ -Axis drive from both
t he Α Sweep L ogic circuit
and

Α front-panel
PROBE ADJUST output is p rovided
for use
the Alternate Β Sweep
circuit is applied to the Ζ -Axis
Ampli-

in

adjusting

probe
compensation .

The voltage

at
the
fier . The output signal
from the Ζ -Axis Amplifier circuit sets

PROBE ADJUST
connector is α negative-going
square
the crt intensity . When using Chop
V ertical mode, α b lanking

wave that h as α p
eak-to- p eak am p litude of
approximately
0 .5 V and α repetition
rate of approximately
1 kHz .
DETAILED
CIRCUIT
DESCRIPTION
VER TICA L ATT
ENU ATO RS

I np ut Cou p
ling
Theory of
Operation-2235 Service
The signal applied
to the CH 1 OR Χ i nput
connector can
The Channel 1 and Channel 2 Attenuator
circuits, shown

be ac cou p le d , do
coupled, or disconnected from the
input of
on
Diagram 1, are identical
with t he exception of the addi-

the
High-Impedance
Input Attenuator circuit .
Signals applied
tional Invert circuitry in the Channel
2 Paraphase Amplifier .

to the CH
1 OR Χ in p ut connector are routed
through resis-
Therefore, only the Channel 1 Attenuator
will b e described

for R 9100
to Input Coupling switch S1 .
When S1 is set for
and
the Invert circuitry of Channel
2 will be d iscussed

do
coupling, the Channel 1 signal is applied directly to
the
sep
arately .

input of the
High-Impedance Attenuator stage .
When ac
coupled, the
input signal passes through dc-blocking
capac-
itor C2 . The b
locking capacitor prevents the d o com
ponent
The Attenuator
circuit (see F igure 3-1) p
rovides control of

of the input
signal from being app lied to the
Attenuator cir-
input
coupling, vertical d eflection factor, and
variable volts-

cuit . When
switched into the signal p ath, attenuators
ΑΤ 1
p er-division
gain . Input signals for crt
vertical deflection may

and ΑΤ 2 attenuate
the in p ut signal by factors of 100 and
10
be
connected to the CH 1 OR Χ and the
CH 2 OR Υ input

res p ectively . When
S1 is set to GND, the direct
signal p ath
connectors . In the Χ - Υ mode of operation, the
signal applied

is openedand the
input of the B uffer Amplifier is
connected
to the
CH 1 OR Χ connector p rovides
h orizontal (X-Axis)

to ground .
This
p
rovides α ground reference
without the
deflection
for the display, and the
signal applied to the CH 2

need to
disconnect the applied signal from the
input connec-
OR
Υ connector provides the vertical
(Y-Axis) deflection for

tor .
The coupling capacitor precharges
through R4 to p re-
the
dis p lay .

vent
large trace shifts when switching from GND to
AC .

Tektronix 2235 Specifications

General

Brand	Tektronix
Model	2235
Category	Test Equipment
Language	English