Heathkit HD-1250 - Circuit Board Checkout

16
START
)
S21.
Pushbutton switch.
Be
sure
to
push the switch
firmly, all
the way
down onto the circuit board. Then
solder its six lugs
to
the foil.
( )
C21A, C21B.
Tuning
capacitor.
Mount the capacitor to the circuit
board
with three
6-32 x
3/16"
screws
and three #6
flat washers
as
shown below. Be
sure
to
place the
flat washers
between the capacitor
and the circuit board.
m,
FLAT
WEI
CUT GROUND
TERMINAL TO
5/8"
3
V*
%
3
/a
1 (INCHES) 2
I 1/B .
3/8 I 5/8
7/8
I . I
ImM"^
1
'i
1
1
1
i
1
1
i
CONTINUE
(
)
Cut the ground lug to
5/8"
from the
corner of the
tuning capacitor
frame.
(
)
Refer
to
Detail 1-3A and form the
ground lug as
shown.
CIRCUIT BOARD
CHECKOUT
Carefully
inspect the
circuit board
for the
following
conditions.
(
)
Unsoldered connections.
NOTE: Do
n« solder
tuning capacitor
lug 1
.
(
)
"Cold" solder
connections.
(
)
Solder
bridges
between foil patterns.
( )
Protruding leads
which could touch
together.
{
)
Transistor
for the
proper installation.
(
)
Diodes
for the correct
position
of
the|
banded end.
(
)
Be
sure the case
of transistor Q21 does
not
touch tuning
capacitor lug 1
.
NOTE: At this time, there are two
small
unused holes in the circuit
board.
Set the circuit board aside
temporarily.