Circuit
Description
—Type
575
Fig.
3-4.
Modification
of
Fig.
3-3.
As
the
plate
voltage
of
VI
71
falls,
the
cathode
voltage
of
V163A
also
falls,
discharging
Cl77.
The
cathode of
V163A
is
prevented from going
below
ground
potential
by
conduc
tion
of
V152A.
Because
the
Miller tube grid is
clamped
at
ground
potential
by
V152B,
its
plate
voltage
will
quickly
reach
an
equilibrium
condition.
As
the
cathode
voltage of V163A falls,
so
do
the
voltages
at
the cathode
of
V143B
and
the
grid
of
V155A.
If
they
go
more
negative
than
—
58
volts,
V155A
will
be cutoff,
V155B
will
conduct,
V152B
will
no
longer
clamp
the
grid
of
the
Mil
ler
tube,
and
the
stepping
process
will
be
resumed.
Note
that
the
cathode
circuit
of
V143B
consists
of
a
resistor
shunted
by
a
capacitor.
If V143B
is
driven
below
cutoff,
the
rate
of
fall
of
the
cathode voltage
will
be
limited by
the
dis
charge
rate
of
Cl
86
through
R186.
This
time-delay
circuit
affects
only
relatively
fast
negative-going
signals;
positive
going
signals are
not
delayed.
Cl
80
emphasizes
rapid
changes
in the
output
signal
at
the grid of V143B,
and
tends
to
compensate for the
loading
effect
of
Cl
86
in
the
positive
direction.
The
time delay
in
the
negative
direction
is necessary
to
allow
Cl
77
to
be
discharged
to
the
point
where
the
output
voltage
of
the
Step
Amplifier
has
fallen
to
the
base
level
before
the
Schmitt trigger reverts and permits the
stepping
process
to be
resumed.
Single-Family
Triggering
On the circuit
diagram
of
the
Step
Generator, notice
the
section
of
switch
SW145 which is
shown
near
C143B.
In
the
OFF
position
of
SW145,
a
voltage
divider
formed by
R184
and
R186
fixes
the
grid
voltage
of
V155A
to
keep
it
in
con
duction.
As
a
result,
V155B
is
cutoff,
disabling
the
Staircase
Generator.
The
display
of
a single
family
of
curves
requires
that
the
Schmitt
trigger
change to
its
other conduction
state
long
enough
for
the
desired
number
of
steps
to be
generated,
then
revert
to
the
OFF position
condition. To
start
the
generation
of
one
stairstep
waveform,
the
top of
Cl
46
is
grounded
by
depressing
SW145
to
the
SINGLE
FAMILY
position.
This
drops
the
grid
of
V155A
about
50
volts,
causing
the trigger
circuit
to
change
to
its
other
state
(V155B
conducting).
When
V155B
conducts,
VI
71 is
no
longer
clamped
and
the
staircase
generator
is
ready
to
generate
a
series
of
voltage
steps.
When
the
desired number
of
steps
has
been
gener
ated,
V143B
acts
in
the usual
way
to
bring
V155A
into
con
duction
again.
Pulse
Generator
The
circuit
diagram
of
the step
Generator
shows
the
split
load
phase
inverters, V104A
and
V124A,
driven
by
sine
waves
at
the
power-line
frequency.
The
single
angle
be
tween
these
signals
is
adjusted
to
90
degrees
by
the
RC
net
works
R102/C102
and
R122/C122.
The
resulting
waveforms,
A
and
B,
are
shown
in
Fig.
3-6;
the
voltages
are
approxi
mate.
The output
of
each
phase
inverter
is
rectified to
pro
duce
a
pulsating de
waveform
(C)
(D)
at
a
frequency
of
120
cps.
The
rectified
outputs
of
the
phase
inverters
are
fed
into
two
pentodes (V104B and
V124B)
having
a
common
plate-
3-4
Содержание 175
Страница 4: ...VWTICM OINltAlO TRANSISTOR CUM TRACfR UB l COUlClO r hokizoniai VCKIJ O lUnK Hix M Type 575 z ...
Страница 6: ...NOTES ...
Страница 26: ...NOTES ...
Страница 48: ...NOTES ...
Страница 54: ...Recalibration Type 575 C706 Fig 5 3 Left Side View 5 6 ...
Страница 56: ...NOTES ...
Страница 61: ...O I Ui Fig 6 6 Simplified circuit diagram of Type 175 Transistor Curve Tracer High Current A dapter ...
Страница 100: ...INPUT AMPLIF1E ...
Страница 104: ...TYPE 575 TRANSISTOR CURVE TRACER ...
Страница 108: ...OSCILLATOR 4OOV UNREG TYPE 575 TRAN5I5TOR CURVE TRACER AB ...
Страница 114: ...234 VAC 117 VAC PRIMARY CONNECTIONS FOR 234VOLT OPERATION ___I TYPE 175 TRANSISTOR CURVE TRACER HIGH CURRENT ADAPTOR ...
Страница 115: ... 300 ...
Страница 117: ...TYPE 175 TENT S N 393 PARTS LIST CORRECTION CHANGE TO SW510 TRANSISTOR SELECTOR 260 636 M6983 664 ...
Страница 119: ...Type 175 Tent S N 570 PARTS LIST CORRECTION Change to Q233 151 0137 00 2N21U8 MIO 298 1165 ...
Страница 123: ...INSTRUCTIONS cont uu y uj r uu y P 2AO MJ i DfeZOC 4K cx zdd uu gn UJ bK uj bn T JU O Page 4 of 4 040 0223 00 ...
