Panasonic RX-1490/A - Dial Threading; Dial Cord Routing Diagram; Measurements and Adjustments; Alignment Procedure and Instructions

RX-1490/A RX-1490/A
@ ALIGNMENT POINTS
@ DIAL THREADING
Pointer
®Turn tuning Capacitor to fully
counterclockwise direction
eTurn drum to fully
clockwise direction
Fig. 6.
MEASUREMENTS AND ADJUSTMENTS
@ ALIGNMENT INSTRUCTION
READ CAREFULLY BEFORE ATTEMPTING ALIGNMENT
1. Set volume control to maximum.
2. Set tone control to treble.
3. Selector switch to AM or FM.
@ AM AND FM ALIGNMENT
SWEEP GENERATOR RADIO DIAL
BAND SETTING
Fashion loop of
several turns of 455 kHz
wire and radiate 30% Mod.
signal into loop of at 400 Hz
receiver.
4. Set power source voltage to 7.5 V DC.
5. Output of signal generator should be no higher than
necessary to obtain an output reading.
INDICATOR
VOCIMEILE. | ADJUSTMENT REMARKS
or SCOPE)
AM-IF ALIGNMENT
Point of non-
interference. (on/
about 600 kHz)
Output meter T3 (AM 1st IFT) Adjust for maximum
across voice coil. | T4 (AM 2nd IFT) output.
AM-RF ALIGNMENT
525 kHz Tuning capacitor 6(AM OSC) Adjust for aximum
fully closed. Coil) =
1 et kHz | Tuning capacitor CT4 (AM OSC
|, nae open. Trimmer)
moving coil bobbin
550 kHz Tune to signal. (*1) L5 (AM
ANT Coil)
along ferrite core.
Adjust for maximum
1,500 kHz CT3 (AM ANT output.
Trimmer) Repeat steps
(2)~(5).
(*1) Cement antenna bobbin with wax after completing alignment.
FM-IF ALIGNMENT
ae for maximum
output. Adjust L5 by
High side thru. Connect vert.
(6) FM 0.001 uF to test 10.7 MHz Point of non- amp. of scope Adjust for maximum
point W . Negative (SWP.) interference. (on/ totest point YW. | 71 (FM 1stiIFT) amplitude.
av to test point about 90 MHz) Negative y to (Refer to fig. 8.)
test point W
Adjust for maximum
T2 (FM 2nd IFT) amplitude.
(Refer to fig. 9.)
FM-RF ALIGNMENT
W through FM dummy
antenna. Negative
side to test point 8.
Variable Output meter L4 (FM OSC (*2) Adjust for maxi-
(8) FM 86.2 MHz capacitor across Coil) mum output.
Connect to test point fully closed. voice coil.
9) FM
Lad
109.3 MHz | Variable capacitor CT2 (FM OSC
fully open. Trimmer)
106 MHz CT1 (FM ANT
Trimmer)
(*2) Three output responses will be present; proper tuning is the center frequency.
(#2) Adjust for maxi-
mum output.
Repeat steps
(8)~(10).
(10) FM
109.3MHz
Fig. 8
FM 2nd
10.7MHz
|
Fig. 9
Fig. 10
<RADIO>D
Telescopic ANT
IC |
FM RF AMP/CONV
FM IF/DET &
AM RF/CONV/IF/DET
B+
(A)
< RECORD >
»
C-MIC
|
5
VRI-VR2
VOLUME TONE
0 3 Jl
| EXT SP
—— ° SPEAKER
J2 o oO ] WOOFER
l2cm (4 23/45" )
3N
a f|SPEAKER
ee Otweerer
0
O
3
REC
3cm
(1
3/16")
4nN
R/P
»
LO
HEAD
<PLAYBACK>
S2-5
S2-3
VRI-VR2
-
VOLUME
TONE
T
|
EXT
SP
:
WOOFER
P
z=
l2écm(4
23/30
)
R/P
3N
HEAD
SPEAKER
SOP Weeren
3cm (1 3/16') 40
Fig. 11