Marantz 3600 - Times Ten (X10) Amplifier; Tone Control;Turnover Network; Time Delay Relay; Tests and Adjustments

B. TIMES TEN (X10) AMPLIFIER
The X10 Amplifier increases the signal level to
that required to drive power amplifiers. The
output of the X10 Amplifier is applied to an
Active Filter Network comprised of three filter
circuits (30 Hz, 5 kHz, and 9 KHz) and a Filter
Amplifier stage. The Active Filter Network
sharply reduces low- and/or high-frequency noise
that may originate at the program source. The
output of the filter amplifier is applied to the
Tone Control/Turnover Network comprised of
the Bass, Mid, and Treble Tone-Control circuits,
the 250 Hz and 4 KHz Turnover circuits, and a
Tone Amplifier stage. The output of the Filter
Amplifier is also applied to the Tone Switch.
C. TONE CONTROL/TURNOVER NETWORK
The Tone Control/Turnover Network performs a
dual function. The tone control portion of the
network boosts or attenuates low, middle, and
high frequencies. The turnover portion of the
network decreases (in frequency) the low/middle-
frequency locus (turnover) point at which the
bass control becomes effective and/or increases
(in frequency) the middle/high-frequency turn-
over point at which the treble control becomes
effective. The Tone Switch selects either the
flat output of the Filter Amplifier (bypassing
the tone controls) or the. tone-control-altered
output of the Tone Amplifier. From the Tone
Switch, the signal is applied to the Time Delay
Relay.
D. TIME DELAY RELAY
The circuit associated with the Time Delay Relay
causes the relay contacts to remain open for
approximately five seconds after power is applied.
During the five-second interval, the power supply
circuits stabilize and the relay contacts close.
Audible "pops’’ from power supply transients
are hereby eliminated.
From the contacts of the Time Delay Relay, the
signal is applied to the preamplifier outputs to
drive an external power amplifier. The power
amplifier outputs are applied to the Speaker
Switching Inputs and the signal is applied to the
2
stereo Phono jack. The power amplifier signal
is also applied to the Main and/or Remote
Speaker terminals by the corresponding Speaker
switch.
TESTS AND ADJUSTMENTS
A. TEST EQUIPMENT
Tests and adjustments in the following paragraphs
are
based
on
the
use
of
the
Recommended
Test
Equipment
listed
in
Table
1
or
their
equivalent.
A.C.
Power
Control!
Box
and
Test
Equipment
Connection
Diagrams
are
shown
in
Figures
4
and
5 respectively.
B. PRELIMINARY PROCEDURE
1.
Set
controls
on
A.C.
Power
Contro!
Box
as follows:
Line Switch .........0000-c eee OFF
Phase Switch.............. NORMAL
Wattmeter Switch................ IN
Autotransformer .. Minimum (Full CCW)
2. Set Model 3600 controls to the ’’Normal”
condition (any variation of these settings
in this section will be so noted):
Program Selector ............. Tuner
Mode ............0. bd Shao Stereo
Volume ....... Minimum (Full CCW)
Balance 1... ... cece cee eee Mid
Tone Switch .............000, Out
Tape Monitor .............. Source
Turnover Switches ............. Out
Filter Switches ..............00. Out
Loudness Switch ............00. Out
Tone Switch ............. 0002 ae Out
Tone Controls ...........00000. Mid
3.
Install
shorting
plugs
in
Aux
Input
jacks.