UNBLANKIMG
PULSE
V/&2A
+GATE
R.I4O
4
al
BLOCK
DIAGRAM DESCRIPTION
The block
diagram
shows
the
interconnection
of
the
functional
parts
of
the
oscilloscope,
except
the
power
supplies.
Functions
of
the
switches
are
shown
instead
of
their actual
connections. This diagram,
as
well
as
the
ones
which
follow,
is
designed
to
fold
out
so
that
the
diagram
can
be
studied
along with
the
text without
turning
any
pages.
The
vertical
amplifier
has
a
sensitivity of
.05
volt
per
centimeter
(.1 volt
per
centimeter
S/N
101-1000)
and
provides
push-pull
output
to
drive
the
deflection
plates.
The
balanced
delay
line is connected
between
the
output
amplifier
and
the
deflection
plates.
The
trigger
cathode
follower
applies
a sample
of
the
vertical
signal
to
the
trigger-amplifier
stage
to
provide
internal
triggering.
The
trigger
amplifier
and
shaper
provide
a
sharp
trigger
pulse
which
triggers
the
multi
vibrator.
The
multivibrator
gates
the
time
base
generator and
is prevented
from
recycling
by
the
holdoff
cathode
follower
until
the
generator
has had
time
to
run up
and
return.
The
time-base generator
is
a
Miller
run-up
type
and
provides
a
150-volt sawtooth for
the
horizontal amplifier.
The
horizontal
amplifier converts
the
time
base
sawtooth
for
push-pull
applications
to
the
deflection
plates.
The
unblanking
cathode
follower
applies a
positive
gate
to
the
crt
grid
via
the high-
voltage
power
supply.
It
also
supplies
a
gate
to
the
gate-out
cathode
follower
which provides
a
positive
gate
at
a front-panel
binding
post.
SECTION
3
CIRCUIT
DESCRIPTION
The
calibrator
provides
a
square
wave
of
known
amplitude
for
checking
the
gain
of
the
oscilloscope
amplifiers
and
auxiliary equipment.
VERTICAL-DEFLECTION SYSTEM
General
The
Type
515/515A
vertical
amplifier
has
a
maximum
sensitivity
of
.05
volt
per centimeter
(.1 volt
per
centimeter
S/N
101-1000),
ac
or
de.
The
circuit consists
of
two
stages of
amplification,
each
stage preceded
by
cathode
followers.
Input
Connectors
There
are
two
input
connectors
which can
be
switched
into the input
circuits by
SW
301,
the
INPUT
SELECTOR
switch.
This
switch
is
wired
physically so
as
to
reduce
coupling
between
inputs
to
a
minimum. Blocking
capacitor
C301
is
shorted
out
in
the
DC
positions
of
the
selector
switch.
I
nput
Attenuators
The
VOLTS/CM
switch
inserts
frequency-
compensated
attenuators
into
the
input
circuit.
Four
attenuators
are used
singly
or
in
tandem
pairs
to
produce
nine
fixed
sensitivities.
DC
Balance
The
DC BAL
control, R338,
provides
an
adjustable,
de
grid
voltage
for
V340
so
that
the
cathode
of
V360
is at
the same
potential
as
the
cathode
of
V350.
When
this
control
is
properly
set,
no
change
in
vertical
position
ing
will
result
when
the
VARIABLE
position
is
rotated.
AA
Circuit
Description
- Type
515/515A
3-1
