Graymark 803 - HOW YOUR PROJECT WORKS; Transformer Circuit Function; Rectifier Circuit Function; Filter Circuit Function

HOW
YOUR
PROJECT WORKS
Your Model
803 solid-state
Power Supply
consists
of four
stages
of circuitry:
power
transformer circuit, rectifier
cir-
cuit, filter
circuit, and voltage
control circuit.
TRANSFORMER
CIRCUIT
Transformer T1 is
used to step
voltage
to the
voltage required
Por,ver
Supply.
dorvn the
110-12A VAC line
for
proper
operation of the
RECTIFIER CIRCUIT
Diocles
CRl
and
CR2
are rised as
rectifiers.
That is, they
are
used to change the alternating current
(AC)
frorn the trans-
former to
pulsating
direct current
(DC).
FILTER
CIRCUIT
The fiiter
circuit
cctr.rsists
of capacitors Cl and
C3,
and re-
sistor
R.l. The1,3re
used t9 srngttth
out the
pulsations
of the
DC,"'oltage
frorn the recifier
cliocles.
UUN IHOL
CIRCUIT
The
control c ircLr it
consisls of zener
diode CR3, resistor R2,
pote,ntiorneter
R-l
,
capacitor
C2, and transistor
Q1.
The
transistor acts as a i,ariable
resistor
to control the outpirt
i,oltage and
js,
in
turn, controlled
by the
potentiorneter.
20
LEARNING
EXPERIENCE
AND
SKILL DEVELOPMENT REVIEW
This
project
has
afforded
you
the opportunity
of expanding
your
knowledge
of electronics
and electrical
devices through
experiments
and
related
techni-
cal
informalion.
You will probably
be surprised at
the
number
of skills
you
have learned
and
the
amount
of
knowledge you
have
acquired from
building
this project,
such
AS:
o
ldentification
of
electronic components
.
What rectification
is
and does
o
ldentification
of schematic symbols
o
How transformers
function
.
How to
read resistor
color
codes
o
How
diodes function
.
How
to read
schematic
diagrams
o
Capacitance
filtering
.
How
to read block
diagrams
.
How
to
calculate
.
How
to
solder
properly
percent-of-ripple
.
use
of hand tools
o
safety
precautions
.
Use of
test
equipment