Harman Kardon 75+ - Installation and Setup; Ventilation and Speaker Placement; Power Requirements and Fusing; Speaker Connection and Impedance

AM ALIGNMENT PROCEDURE
INSTRUMENTS: SSG, modulated with 400Hz at 30%, V.T.V.M., AM IF Sweep Generator, and Oscilloscope.
NOTE: Set FUNCTION selector to AM.
Connect signal source to a loop placed to radiate signals into AM ANT LOOP STICK.
SIGNAL SOURCE
CONNECT OUTPUT
Step
OUTPUT
METER TO
DIAL SETTING
ADJUST
ADJUST FOR
1 455kHz of sweep
V.T.V.M. & oscillo-
Quiet point near T162 (Black)
Maximum and
-
generator
scope to TAPE OUT 1600kHz
symmetrical
2
T161, input side
pattern on SCOPE
~
3
T161, output side
4
Repeat step 1 through 3 for best sensitivity and symmetrical pattern on oscilloscope.
5
525kHz of S.S.G.
V.T.V.M. to TAPE Gang fully closed L 162 ( Black)
OUT 1 and distortion
meter together with
Maximum output
6
1700kHz of S.S.G.
oscilloscope to Gang fully opened AM oscillator
speaker out
trimmer
7 Repeat step 5 and 6 for best sensitivity
8 600kHz of S.S.G.
600kHz
AM ANT LOOP
Same as above STICK
Same as above
9
1400kHz of S.S.G.
1400kHz
AM ANT trimmer
10 Repeat step 8 and 9 for best sensitivity.
SIDE CHAIN ALIGNMENT FOR MUTING & STEREO THRESHOLD
Step SIGNAL SOURCE
OUTPUT METER 11
ADJUST
ADJUST FOR
14 Repeat 1, 2 and 3 for optimum setting.
15
STEREO THRESHOLD
1.50V on DC voltmeter
VR012.
~
Connect SSG to FM ANT D.C. Voltmeter
16 terminal. from ground to L101 and SSG output.
Maximum on DC voltmeter;
Quiet point near 98MHz.
R141.
keep DC voltage to 1.50V
SSG set on CW
by adjusting SSG output.
TUNING indicator, M101
must indicate zero center
all times.
17 Same as above, but set
MUTING ADJUSTER,
Finally, audio output must
SSG output to 26dB.
VR 101.
drop by 3dB with FM
(or 20 µV)
MUTING switch ON.
18 Check again zero center on TUNING INDICATOR, M101 with no signal.
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