Filter
Top Products
Introduction
For
ease
in
understanding,
this
description
r
efersto the
schemat
i
cs
located
in
t
he
pullout
p
ages
at
the
r
ear
of
this
m
anual
.
Also
r
efer
to the
b
lock
diagram
located
in
t
he
pullout
pages
and
t
he
timing
diagram
in
Fig
.
3-1
.
E
ach
block
in
t
he
b
lock
diagram
is
outlined
on
t
he
schematics
.
The
TM
5006
uses α
pulse
width
modulated
switching
su
p
ply
for
do
voltages
.
Α
60
Hz
t
ransformer provides
the
ac
voltages
n
ecessary
for
plug-in
operation
.
Connections
to
the
six
plug-in
compartments
as
well
the se
ιί
es
p
ass
transistors
are
shown
on
schematic
3s
.
Line
Selector
and
60
Hk
Transformer
R
ectifiers
and
Filters
0
T
HE
O
R
Y
O
F
O
PER
ATIO
N
Ac
power
is
appl
i
ed
to
the
voltage
select
terminals
through
FL500
and
α
d
i
screte
line
filter
composed
of
Τ
1050,
L
1030
and
L1020
.
L
ine
transients
a
re
filtered
to
ground
t
hrough
C1120
and
C1140
.
The
two
primary
windings
on
Τ
500
are
connected
in
p
arallel
for
115
V
o
peration
or in series
for
230
V
opera-
tion
.
W
inding
taps are
provided
for
various
line
voltages
around
t
he
n
ominal
values
.
T
he
secondaries
provide ac
voltages
to
the
various
plug-in
compartments
.
The
ac
line
voltage
is
applied
t
hrough
negative
te
m
perature
coefficient
ι
esistances
R
T1000
and
RT1200
to the
r
ectifier
d
iodes
.
4s
these
r
esistances
are
h
ighest
when
cold,
the
surge
currents,
charging
the
h
igh
voltage
capacitors
when
line
voltage
is
applied,
are
limited,
thus
preventing
component
failure
.
T
hese
r
esistors
then
self
heat to α
low
resistance
.
In
220
V
o
peration
t
hefour
diodes
function
as
α
bridge
r
ectifier
.
See
F
ig
.
3-2
When
t
he
voltage-select-circuit
is
set
for
110
V
operation,
onlythetwoseriesd
iodes
operate
.
The
circuit
then
becomes
avoltage
doubler
with
an
o
utput
of
approximately
350
V
dc
.
The
neon
bulb
in
t
his
circuit
flashes
to
indicate
when
do
voltage
is
present
.
T
he
rectified
a
nd
filtered
do
is
applied
t
hrough
L1320
and
C1240,
α
low
pass
filter,
and
passes
t
hroug
h
81430
and
C
R1540,
to
the
collector
of
01640
.
20
kHz
Output
Stage
The
output
stage
is
α
h
alf
b
ridge
type
with
proportional
b
ase
drive
.
The
turns
r
atios
and
phasing
of
T1
740
ares
uch
t
h
at
only
α
s
mall
amount
of
b
ase
drive
power
is
n
eeded
to
start
conduction
in either
01640
or
01650
.
P
ositive
feedback
f
rom
Τ
1740
s
upplies
b
ase
current
for
t
he
remainder
of
the
p
ower
cycle
.
When
both base
d
rive
tra
n
sistors,
01730
and
01731,
(shown
on
schematic
are
saturated,
Τ
1740
is
essentially
shorted,
te
ι -
mi
λ
(ating
b
ase
current
for either
output
transistor
.
Output
transistors
01640
and
01650
alte
r
nately
conduct
at
α
20
kHz
rate
.
Their
on
a
nd
off
times
are adjusted by the
r
egulation
circuitry
.
Diodes
CR1550
and
C
R1551
prevent
b
ase
to
collector
c
urrent
flow
i
η
01640
and
01650
at
turn
off
.
The
b
ase
switching action
of
these
transistors
is
improved
by
networks
C1530
and
81530
for
01640,
and
C1560
and
R1460
for
01650
.
Α
series
r
esonant
filter
between
t
he
transistors
and
t
he
output
transformer,
Τ
1710,
is
composed
of
C1430
and
L1440
.
During
01640
and
01650
off
time,
the
tank
current
generated
by
L
1440
and
C1430
passes
through
C
R1541
and
C
R
1551
.
The
20
kHz
output
voltage
is
stepped
down
to
t
he
correct
levels
b
y
Τ
1710
.
T
hree
sets of
full
wave
d
iode
rectifiers
a
re
provided
for
each
of
the
three
d
o
voltage
outputs
.
Schottky
d
iodes
are
u
sed
in
t
he
+8
V
s
upply
for
reduced
forward
voltage
drop
.
All
filters
are
L
-C
p
i-sections
.
Bleeder
resistors
are
provided
for
all
filter
capacitors
.
Co
n
trol L
ogic
and
D
rivers
Section
3-TM
5006
U
1840E
a
nd
U1840F
are
inverting
amplifiers
.
Their
outputs
control
the
b
ase
drive
transistors
01730
and
01731
.
Collector
voltage
for
t
hese
transistors
is
applied
f
rom
t
he 10
V
bus
through
α
center
tapped
winding
on
the
b
ase
drive
transformer
(
Τ
1740)
.
R
everse
p
olarities
across
01730
or
01731
are
prevented
b
y
CR1730
and
CR1731
.
When
either
one
or
b
oth
of
these
transistors
(01730,
01731)
are
on,
either
o
ne
or
both
of
the
output
transistors
(01640
;
01650)
are
off
.
The
b
ases
of
ο
1
730and
01731
are
also
controlled,
through
R1832
and
81950,
b
y
the
collec-
tor
of
02240
.
During
p
ower
up
or
p
ower
down,
the
collector
of
02240
goes
p
ositive
.
This
action
t
urns
01730
and
01731
on
to
turn
t
he
output
transistors
off
.
This
is
n
ecessary as
t
h
e
control
circuitry
state
is
undefined
during
power
up
o
r
power
d
own
.