Heathkit HP-23A - Troubleshooting and Problem Solving; General Troubleshooting Information

Page 14
() Connect the power cable from the Power
Supply to your equipment.
()
Connect
the
line
cord
plug
to
an
electrical
outlet
supplying
the
voltage
for
which
the
Power
Supply
was
wired
(120
VAC
or
240
VAC),
(_
)
Select
the
desired
low
B+
voltage
by
moving
the
AC
OFF
switch
tothe
right
for
350
VDC,
or
to
the
left
for
275
VDC,
If
your
equipment
does
not
have
provisions
for
remote
control
of
the
Power
Supply,
this
will
turn
the
Power
Supply
ON,
(Plate
and
filament
voltages
are
always
turned
on
and
off
simultaneously.)
(_)
If
your
equipment
has
provisions
for
remote
control
of
the
Power
Supply,
turn
the
equip-
ment
off-on
switch
to
ON,
() If you are using the adjustable bias, adjust
the bias voltage as necessary with the BIAS
ADJUST control,
()
The
Power
Supply
may
be
turned
off
by
the
AC
OFF
switch
onthe
chassis,
or
by
the
off-
‘on
switch
on
your
equipment,
provided
that
it
was
wired
for
remote
control,
IN
CASE
OF
DIFFICULTY
‘This
section
of
the
Manual
is
divided
into
two
parts,
The
first
part,
titled
General
Trouble-
shooting
Information,
describes
what
todo
about
any
difficulties
that
may
occur
right
after
the
Power
Supply
is
assembled,
‘The
second
part,
a
Troubleshooting
Chart,
is
provided
to
assist
in
servicing
ifthe
General
In-
formation
does
not
clear
up
the
problem,
or
if
difficulties
occur
after
the
Power
Supply
has
been
in
operation
for
some
time,
This
Chart
lists
some
difficulties
which
could
arise,
and
several
possi-
ble
causes,
GENERAL
TROUBLESHOOTING
INFORMATION
1,
Recheck
the
wiring,
Trace
each
leadincol-
ored
pencil
on
the
Pictorial
as
itis
checked,
It
is
frequently
helpful
tohave
a
friend
check
your
work,
Someone
whois
not
familiar
with
the
unit
may
notice
something
consistently
overlooked
by
the
builder.
2,
About
90%
of
the
kits
that
are
returned
to
Heath
Company
for
repair
do
not
function
properly
due
to
poor
connections
and
solder-
ing.
Therefore,
many
troubles
can
be
elimi-
nated
by
reheating
all
connections
to
make
sure
that
they
are
soldered
as
described
in
the
soldering
section
of
the
Kit
Builders
Guide.
3.
Check
the
values
of
the
parts,
Be
sure
that
the
proper
part
has
been
wired
intothe
cir-
cuit,
as
shown
in
the
Pictorial
diagrams
and
as
called
out
in
the
wiring
instructions,
4,
Check
for
bits
of
solder,
wire
ends
or
other
foreign
matter
which
may
be
lodged
in
the
wiring,
5,
If,
after
careful
checks
the
trouble
is
still
not
located,
check
voltage
readings
against
those
on
the
Schematic,
NOTE:
All
voltage
readings
were
taken
with
an
11
megohm
input
voltmeter,
Voltages
shown
are
with
no
load
on
the
output,
6.
A
review
of
the
Circuit
Description,
and
a
study
of
the
Schematic
Diagram
will
help
you
locate
a
difficulty
in
the
Power
Supply.
7.
Check
for
loose
hardware,
Be
especially
careful
that
metal
capacitor
mounting
wa-
fers
and
terminal
strip
mounting
feet
are
well
grounded,
NOTE:
Inan
extreme
case
where
you
are
unable
to
resolve
a
difficulty,
refer
to
the
Service
and
Warranty
sections
of
the
"Kit
Builders
Guide",
andtothe
"Factory
Repair
Service"
information
on
the
fold-out
from
Page
18
of
this
Manual.