Marantz 3800 - Page 19

to their normal settings upon completion of the
functional tests both channels.
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(1)
(2)
2-4
For low level (Phono or Mic) input tests,
apply a 1 kHz, 10 mV audio signal to
PHONO INPUT |. Depress PHONO |
Switch.
Set Distortion Analyzer controls for AC
VTVM and monitor output at SCOPE or
TAPE OUTPUT Jack. Output should be
approximately 1 V rms.
Repeat at PHONO INPUT 2, depress
PHONO 2/MIC Switch.
Without changing oscillator output level,
disconnect from PHONO INPUT 2 and
reconnect in front at MICROPHONE Jack.
Output should remain at approximately
1 Vrms.
For high level (Tuner, Aux, or Tape) in-
puts, turn preamp power off, set oscilla-
tor to 1 kHz, 300 mV rms output.
Connect to TUNER INPUT Jack. Re-
connect Distortion Analyzer to PREAMP-
LIFIER (PREAMP) OUTPUT Jack.
Turn preamp power on, turn VOLUME
Control to maximum, depress TUNER
Switch. Output should be approximately
3 V rms.
Without
changing
any
connections
other
than
inputs,
check
AUX,
TAPE
1,
and
TAPE
2
OUTPUTS
as
described
in
Step
(6).
Output
level
should
remain
at
approximately
3
V
rms.
MAXIMUM
VOLTAGE
OUTPUT
Depress
AUX
Switch.
Connect
oscillator
to
AUX
INPUT
Jack.
Monitor
signal
at
PREAMP
OUTPUT
Jack
with
oscilloscope
and
distortion
analyzer
controls
set
for
AC
VTVM.
Turn
VOLUME
to
maximum.
Set oscillator frequency to 1 kHz and
increase oscillator output to the point of
just below clipping. VTVM should indi-
cate at least 9 V rms.
(1)
(2)
H.
TOTAL HARMONIC DISTORTION (THD)
With
preamp
VOLUME
Control
turned
to
maximum,
check
THD
at
AUX
INPUT
Jack
at
20
Hz,
2
kHz,
and
20
kHz
(3
V
rms
output).
THD
should
be
less
than
0.025
percent.
Change input to PHONO Jack and depress
PHONO Switch. Adjust oscillator for
3 Vrms at TAPE OUTPUT Jack. Check
THD at 20 Hz, 2 kHz, and 20 kHz. THD
should be less than 0.025 percent.
HUM AND NOISE
Insert
phono
shorting
plug
into
each
PHONO
and
AUX
INPUT
Jack.
Switch
in
bandpass
filter
control.
Turn VOLUME Control to maximum and
depress PHONO Switch. Noise output
should indicate less than 780 microvolts
measured at PREAMP OUTPUT Jack.
Depress
AUX
Switch.
Noise
output
should
indicate
less
than
30
microvolts
measured
at
PREAMP
OUTPUT
Jack.
FREQUENCY
RESPONSE
(PHONO/MIC)
—
Refer
to
Figure
2-3
RIAA
Equalization
Curve
and
Standards
to
verify
unit
conformance.
(1)
(2)
For
Phono
frequency
response
apply
a
1
kHz
signal
to
PHONO
INPUT
Jack.
Connect
AC
VTVM
to
PREAMP
OUTPUT
Jack.
Set
oscillator
output
for
0
dB
indication
on
VTVM.
Check
output
level
at
the
following
fre-
quencies
+
0.5
dB:
PONAE
8
ep
ce
alg
athe
aia
¥
+19.30
dB
TOOTS
lace
te
wted
wee
ae
+13.11
dB
BOO
IAT:
wiseaisieie:
2
deatawede
nets
+3.81
dB
2
KRE
So
Seun
heey
kG
to
-2.61
dB
TOUR
Ze
soe
rsse
eae
ataalt
anaes
-13.75
dB
COKE
2
aan
ca
a
da
vee
as
-19.60
dB
For
Mic
frequency
response
appiy
a
1
kHz
signal
to
MICROPHONE
Jack
(front
panel).
Depress
2/MIC
Switch.
Set
oscillator
output
to
0
dB
as
measy
sed
at
PREAMP
OUTPUT
Jack.