Circuit
Description
—
Type
3B5
Fig.
3-10. Trigger level current for Manual
Mode triggering (non-auto).
the
base
of
Q54
is
pulled
toward
—12.2
volts
by
the
Manual
Power
applied
as
previously
discussed.
The
Trigger
Latch
Circuit
turns
on
and
forward
biases
D52
and
reverse
biases
D9.
When
D9 is
reverse
biased,
manual
level
current
from
the
LEVEL
control,
R25A,
is
connected
to
the emitter
of
Q14
through
DIO.
Fig.
3-10 shows
the
condition
of
the
logic
diodes
for
manual
level
operation.
The
output
of
the
Trigger
Latch
Circuit
rises
to about
zero volts
and
this
level
is
con
nected
to
the cathode
of
D46
through
D52
and
SW50. D46
remains
reverse
biased
and
no
current
flows
through
either
K3
or
K4.
K3-1
remains
in
the
internal
position
and
K4-1
remains
in
the
AC
position.
The
positive
level
at
the
cathode
of
D46
reverse
biases
D43.
However,
the
external
program
level
current
is still
shunted from
Q
1
4 by
D41
due
to
the
Seek/Manual
power
applied
to
it.
Q44
is also
biased
into
conduction
and
its
collector
goes
negative
to
turn
off the
Auto Trigger
light.
With
the
collector
of
Q44 negative,
D37
is
forward
biased
and
the
auto
trigger
level current
is
shunted.
In
the
EXT-AC position
of
SW50,
the
zero-volt
output
of
the
Trigger Latch
Circuit
is
applied
to the
anode
of D46.
D45 remains
reverse
biased
and
current does
not
flow
through
K4.
However,
current
does
flow
through
K3
and
K3-1
switches from
the
internal source
to
the external.
D46
is
forward
biased
and
the base
of
Q44
rises
positive
to
forward bias
it.
The
remainder
of
the
circuit
operates
as
described
for
INT-AC.
In
the EXT-DC
position
of SW50,
the
near-ground
potential
at
the
collector
of
Q54
is
connected
to
the
anode
of
D45.
Current
flows
through
K4
and
K4-1
closes
to
provide
D
C
coupling
of
the
signal
to
the
Input
Emitter
Follower.
Also,
D45
is
forward
biased
and
current
flows
through
K3
to
switch
K3-1
to
the external
trigger
source.
Q44
is
turned
on
through
D46
to
lock
out
the
auto
trigger
level current.
The
remainder
of
the
circuit
operates
as
described
for
INT-AC.
Seek
Mode.
In
the
Seek
Mode,
operation
is determined
by
the
setting
of
the
LEVEL
control, Trigger Function
switch
and
the
presence
(or
absence) of
a
trigger
signal.
As
described
in
the Trigger
Latch Circuit
description,
Q54
is
momentarily
turned
on each
time
a
seek
command
is received
(except in INT-AUTO).
Then,
Q54
remains
on
if
the
unit
is
correctly
triggered
and
operation
is
the same
as
described
for
Manual
Mode (not
auto
triggering).
However,
if
the
unit
is
not
correctly
triggered
or
SW50
is
set
to
INT-AUTO, Q54
turns
off
and
the
instrument
switches
to
auto
triggering.
Then,
operation
is
the
same
as
described
for
auto
triggering
under
Manual
Mode.
If
for
some
reason
the
trigger
circuit
is
no longer
triggered
because,
for
example,
the
level
of
the
trigger signal
has
changed
after
normal
triggering
has
been
established,
the
output
of
the
Trigger
Latch
Circuit
goes
negative.
Manual
trigger
level
current
is
disconnected
and
the
Trigger
Mode
Logic
circuit
reverts
to
auto
triggering.
External
Mode.
In
the
External
Mode
of
operation, the
output
of
the
Trigger
Latch
Circuit
is
negative
as
determined
by
External
Power
applied
to
the
circuit
(see
Trigger Latch
Circuit
discussion).
D9
is
forward
biased
to
shunt the
manual
3-14
Содержание 3B5
Страница 4: ...Fig 1 1 Type 3B5 Automatic Programmable Time Base unit Type 3B5...
Страница 15: ...Operating Instructions Type 3B5 TYPE 3B5 CONTROL SET UP CHART Fig 2 2 Control set up chart 2 7...
Страница 48: ...CO I o Fig 3 13 Delay and Timing Circuit logic block diagram Circuit Description Type 3B5...
Страница 61: ...GO i GO GO Fig 3 22 Seek Ciicuit Logic block diagram Circuit Description Type 3B5...
Страница 70: ...u k KJ Fig 3 29 Circuit conditions for Manual Mode operation Circuit Description Type 3B5...
Страница 71: ...w K w Fig 3 30 Circuit conditions for Seek Mode operation Circuit Description Type 3B5...
Страница 72: ...w I u U Fig 3 31 Circuit condition for External Mode operation Circuit Description Type 3B5...
Страница 88: ...Maintenance Type 3B5 Fig 4 9 Location of components on Logic Card 4 14...
Страница 89: ...u Oi Fig 4 10 Location of components on Counter Card Maintenance Type 3B5...
Страница 92: ...NOTES I...
Страница 104: ...NOTES...
Страница 106: ...Calibration Type 3B5 Fig 6 1 Recommended calibration equipment...
Страница 160: ......
Страница 176: ...J400 RtADOUT BOARD 3B5 PLUG IN A READOUT...
Страница 182: ...397 R E A D O U T B O A R D 10 6b READOUT BOARD...
Страница 184: ...FIG 1 FRONT SWITCHES TYPE 3B5 AUTOMATIC PROGRAMMABLE TIME BASE...
Страница 185: ...FIG 2 CHASSIS REAR 3 GS to TYPE 3B5 AUTOMATIC PROGRAMMABLE TIME BASE...
Страница 186: ...OPTIONAL ACCESSORIES...
