Heathkit HD-1250 - Page 30

Page
28
Refer
to
Pictorial
4-3
for the following steps.
(
)
Position the chassis
assembly top-side-down.
( )
Cut two
3/4"
lengths
of bare wire.
NOTE: Do
not overheat
the connections in the
next
two steps.
{
)
Connect
a
3/4"
bare wire
from tuning capacitor lug 3 (NS) to
coil socket
G
lug
2
(S-1 ). Keep this wire as short as
possible.
( )
Connect the other
3/4"
bare wire from
tuning capacitor lug
2 (NS) to
coil
socket
G lug 1 (S-1). Keep this wire as
short
as
possible.
(
)
Locate the remaining
capacitor lead you saved from the circuit board
assembly.
Cut
a
3/4"
length of this lead. Connect this wire from
the
positive (+) meter lug
(S-1) to
pushbutton
switch
lug
6 (S-2).
NOTE: In the following
steps, the oscillator circuit board will be temporarily
mounted outside the chassis assembly.
This will enable you to
perform
the
"Initial
Tests"
before the small
board is
mounted into
the chassis behind other
components.
( )
Position the oscillator
circuit board
to the right of the chassis, foil-side
toward
you, so the two free
capacitor leads are toward the left
as
shown.
(
)
Place the leads of the two 47 pF mica capacitors through tuning capacitor
lugs
2
and 3 as
shown in the Pictorial.
Temporarily
(lightly) solder these
leads
and
the bare wires to the
tuning
capacitor
lugs.
( )
Apply
a
small amount of solder
to
the indicated corners of the
detector
circuit board. Temporarily (lightly) solder the
upper
and lower lengths
of
braid coming from the oscillator circuit
board to the
corners of
the
detector
circuit
board.
IMPORTANT NOTE: In the next
two steps,
do
not
bend the meter
lugs; this
could permanently damage the meter movement.
( )
Press the small loop
of
wire connected
to
control
R1 lug 3
upward until it
touches the underside of the negative (-)
meter lug as shown
(S-1).
( )
Temporarily (lightly) solder the free end of the blue wire coming from
the
oscillator circuit board
to
control R1 lug
2 (S-1).
This completes
the
initial assembly of your kit. Carefully inspect all connections
for
loose
wires or unsoldered connections. Remove any wire clippings or
solder
splashes. Then proceed
to
the "Initial Test."
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