JBL SG520 - Harmonic Distortion

Step 2. Connect the harmonic distortion analyzer and 10,000-ohm, 4-watt carbon load resist-
or to the OUTPUT TO POWER AMPLIFIER jack of the SG520.
Step
3.
Both
the
oscillator
and
the
distortion
analyzer
should
be
“floated’’
or
isolated
from
the
power
line
grounding
the
system.
This
can
be
done
by
using
a
two-blade
power
plug
adaptor
which
disconnects
the
instrument's
power
cable
ground
pin.
If
the
Hewlett-Packard
oscillator
is
used,
the
output
tragsformer
is
floated
from
the
instrument
chassis
ground.
Do
not
connect
a
common
ground
between
the
oscillator
and
analyzer.
Hewlett-
!
ae
Ne
a
te
ee
el
i
Packard
000
6000
0
60
1
|
Hewlett-Packard
000
0000
0
00
i
|
j
Model 333
Figure 2-1 HARMONIC DISTORTION
2.2.1.2 intermodulation Distortion.—In this procedure, the connection of the Audio Instrument Com-
pany Model 168 Analyzer is described because this unit is easier to use. However, the HP equip-
ment can be used in an equivalent setup.
Step 1. Connect the OSCILLATOR OUT terminals of the intermodulation analyzer to the TUNER
1 jack with a standard shielded cable.
Step 2. Connect a 10,000-ohm carbon load resistor to the OUTPUT TO POWER AMPLIFIER
jack of the SG520.
Step 3. Connect the hot ANALYZER INPUT terminal to the center output terminal of the
SG520.
Make
no
connection
between
the
analyzer
ground
terminal
and
the
common
output
ter-
minal
of
the
SG520.
This
precaution
avoids
the
ground
loop
that
would
be
completed
through
the analyzer common input-output connection.
Audio Inst
Analyzer
Model 168
1900 6000 0 00
|000 0000 0 00
Ilosc OUT ANAL ‘IN
FIGURE 2-2 INTERMOCULATION DISTORTION