Daystrom Heathkit IG-72 Assembly Manual page 19

Paee
16
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(\ )
Arstaff the five
lorot
s
on
the shaJts of the panel controls vrith the pointers at the extreme
counterclockwise marking
on
the panel,
and
tighten the setscrews.
(
) InstaU
the
3
watt
115
volt
candelabra lamp
and
the
6X4, 6AU6, and
6CL6 tubes in
their
proper sockets.
See
tr'igure
14,
(
)
Instau
the handle on the cabinet with 10-24 screws.
(
) Molmt
tfle
lour
rubber
feet
with
6-32
x
1/2"
screws,
#8
flat
washers, #6
lockwashers, and 6-32 nuts as shown in Figure
16.
Figure
16
INITIAL
TEST AND
ADJUSTMENT
Plug the Iine
cord
into a
105-125
volt
50-60
cycle
outlet.
Do
not
plug into
an ouuet
of
higher
voltage
or
Iowerfrequency,
o,
a DC
outtet,
as an
incorrect power source
will
damagethe
trans-
Turn powerswitch
on
andobserve tubes
and
pilot
tampas they
light up.
IJ
they donot Iight, turn
power off
and investigate Iilament
circuit
\?iring.
Set
OSCILLATOR
and
METER controls
about
midway.
Set
precision
(0-100) CYCLEswitchtol0 ormore
and advance OUTPUT
control.
This
should show a reading on the meter.
Calibrate the
meter.
NOTE: IJ in
the loLlowing
test
the OUTPUT control
is teft
oIf or
fuUy
counterclockwise,
it will
be
severly damaged. Prcceed
as
Io[ows:
Turn both CYCLE switches
to
0.
Turn the OUTPUT control to maximum clockwise. Turn
the ATTENUATOR to maximum
clockwise (10
volt or
+20
db).
Connect a
wire
between
the red
output binding postand one of the
pilot light terminals
on
the meter terminai
board.
Use the
terminal that gives a meter indica-
tion.
Turn
the
METEF control to
produce a meter
reading
of
6.3
volts
on
the O-10 scaLe (a
Iit-
tle
over halJ-way
up
the
scale).
Now remove the wire.
II
an accurate AC
voltmeter of
adequate
sensitivity
(at least
500 O
per volt
on
the
10
volt
range
for
instance)
is available,
it
should be used in preference to the above ptocedure.
In that case:
select
a suitable frequency (between 50 and 3000 cycles,
depending on the AC meter
used)
with
the CYCLE
and
MULTIPLIER switches and connect
the
meter to
the output
oI the generator.
Adiust
the
METER control to produce
equal readings on the two meter6.
Adjust the OSCILLATOR control
as
follow6:
No
connections to the output
terminats.
OUTPUT
control
at
maximum.
CYCLE switches and MULTIPLIER to
10 cycles
or
more.
Turn
OSCIL-
LATOR
control
to
give just over lull
scale reading
on
the
meter.
Select
various
frequencies
between 10 cycles
and
100
kc and
iI
the
output drops below fuII scale, readjust
OSCILLATOR
control for full
acale.
Do
not adjust
OSCILLATOR
controt higherthan necessary as higher
than
nominaL
distortion wiII result.
This completes
the adiustment oI
the
instrument. Install the generator
in
the cabinet
anal
lasten
wlth the two
#6
sheet metal screws
throwh
the
rear
of the cabinet into the chassis.
ro