Heathkit HW-9 User Manual

Heathkit
Page
79
VFO ALIGNMENT
( )
Refer
to
Pictorial 5-2
(Illustration
Booklet,
Page
34)
and
use the
blade
of
the shorter
align-
ment
tool
to turn
the
trimmer
of
main
tuning
capacitor
(Cl)
clockwise
until
it
is
just snug.
Then
turn
the
trimmer
counterclockwise
one
full
turn.
(
)
Position
all
wires
in the
area
of the
VFO
circuit
away
from
coil L118
and
the
VFO
tuning
capacitor.
(
)
Connect
your
frequency
counter
to
test
point
TP102.
NOTE:
The
coil
that
you will
adjust
in
the
next
step
has been
preset
close
to its
correct
setting
at
the fac-
tory.
When
you
adjust
this
coil,
be sure
the slug
re-
mains
in
the lower
half
of the
coil.
(
)
Set the
Transceiver
TUNING
DIAL
at the
250
mark
and
adjust
L118
for a
reading
of 5.7493
MHz.
( )
Turn
the
dial
to the
zero
mark
and
adjust
the
trimmer
of
tuning
capacitor
(Cl)
for
a reading
of
5.9993
MHz.
TRANSMIT
RETURN
ADJUSTMENT
( )
Set
your
VTVM
or DVM
to a 15
volt
range
and
connect
its
positive
(
+
) test lead
to
the
lead
of
33
kn
resistor
R127
nearest
TRANSMIT
RE-
TURN
control
R131.
(
)
Make
sure
the
CW LEVEL
control
(on
the front
panel)
is
fully
counterclockwise,
and the
RIT
control
is
in
the
detent
at the
center
of rotation.
Then
note
the voltage
indication
on your
meter.
( )
Key
the
transmitter
by
shorting
the
KEY
input
on the
rear
panel,
or by
holding
down
a regular
key
connected
to
the KEY
input.
( )
Adjust
TRANSMIT
RETURN
control
R131
until
the
transmit
voltage
equals
the
voltage
you
observed
in
the
receive
mode.
Then
dis-
connect
your
meter.
This
completes
the VFO
alignment
and
Transmit
Re-
turn
adjustment.
Proceed
to
"BFO
Alignment."
( )
Repeat
the
previous
two
steps
until
your fre-
quency
counter
indicates
exactly
5.7493
MHz
with
the
dial
at
250, and
5.9993
MHz
at zero.
Then
disconnect
your
frequency
counter.
BFO
ALIGNMENT
Refer
to
Pictorial
5-3
(Illustration
Booklet,
Page
35)
for
the
location
of
the
test
point
and
adjustment
used
in
the
BFO
alignment.
(
)
Connect
your
frequency
counter
to TP
104
on
the
upper
right-hand
side
of the
BFO
shield.
( )
Insert
your
alignment
tool
through
the L135
access
hole
in
the
top
of
the
BFO
shield
and
into
the core
of L135.
( )
Key
the
transmitter
and
adjust
LI
35
for a
fre-
quency
counter
indication
of 8.8307
MHz.
( )
Unkey
the
transmitter
and
the frequency
indi-
cation
should
be
about
8.8314
MHz.
Discon-
nect
the
frequency
counter
from
TP104
and
remove
the
alignment
tool.

Heathkit HW-9 Specifications

General

Brand	Heathkit
Model	HW-9
Category	Transceiver
Language	English