TJIONEEFI
CONDITIONSFREQUENTLYMISTAKENFORMALFUNCTION
N o i s e :T h e r e a r e a v a r i e t yo f n o i s e sr e l a t i n gt o t h e o p e r a t i o no f a h i - fi u n i t . T h e s ea r eg e n e r a l t yd i v i d e di n t o t w o t y p e s ;( 1 ) t h e u n i t is faulty (a transistor or part has deteriorated) and (2) an e x t e r n a ls o u r c e o f n o i s ei s a d d i n gn o i s e t o t h e u n i t .
W h e n a h i - f i u n i t p r o d u c e s a n u n p l e a s a n tn o a s e ,i t i s o f t e n a s s u m e dt h a t t h e u n i t i s f a u l t y , b u t s t a t i s t i c arle c o r d si n d i c a t e t h a t t h e m a i o r i t y o f n o i s e sp r o d u c e di n h i - fi a c o u s t i cu n a t sr e s u l t
f r o m e x t e r n a l s o u r c e s o f n o l s e . D u e t o t h e i n h e r e n t h i g h a m p l i fi e r a n d r e p r o d u c e se x t r a n e o u sn o i s e si n t o d e fi n i t e o u t p u t noise . lf your receivelproducesa noise,check according tothe f o l l o w i n g t a b l e a n d t r a c e o u t t h e s o u r c e o f n o i s e f o r t h e a p p r o p r i a t ec o r r e c t i v ea c t i o n .
SVmptom | SuspectedSourceof Noise |
C o n t i n u o u so r i n t e r m i t t e n | . S t a t i c ( l i g h t n i n g ) |
noiselike jjjjli or zzzzzz . | o Fluorescent lamp, motor, or thermostat |
| may be in use in house or in the vicinity |
| of the house . |
D i a g n o s ias n d R e m e d y
In manv cases, it is very diff icult to remove the source o f n o i s e . I n o r d e r t o m a k e t h e r a d i o i n p u t l a r g e r t h a n the noise level, set up a good outdoor antenna and m a k e a c o m p l e t e g r o u n d i n g
W h e n a s t a t i o n i s t u n e d i n ,
a h u m i s m i x e d i n t h e
o program .
E o
mH i s s i n gs o u n d n o i s ei n A M ( m e d i u m w a v e ) r e c e p t i o n .
o g
o |
|
|
' ? | S t a t i c n o i s e ( i n p a r t i c u l a r , | |
.J | ||
q | w h e na u t o m o b i l e sru n c l o s e | |
o | ||
! | t o t h e h o u s e ) . |
|
= |
| |
|
| |
| Reception of FM | stereo |
| program contains | more |
| noise than FM mono pro - | |
| g r a m . |
|
H u m o r b u z z . W h e n switchedto radio reception,
Ethe noisedisappears .
o E.
.o=
o
O u t p u t t o n e q u a l i t y i s p o o r a n d m i x e d w i t h n o i s e .
oT r e b l ei s n o t c l e a r .
=
rPoor fluorescent lamp, motor, or electric heater may be in use in houseor near the house .
IThe frequency of an adjacent station is interfering with that of the station being
t u n e d i n ( 1 0 k H zb e a t i n t e r f e r e n c e ) .
oT V s e t i s o n i n t h e s a m eh o u s ew i t h t h e receiver .
a White noise generated from automobile engines .
rRadio frequency sewing machine or weld - i n g m a c h i n eb e i n g u s e d n e a r y o u r h o u s e .
a Note that the servicearea coveredby an FM stereo broadcastis about 50% of that of a regularmono broadcast .
aP o o r c o n n e c t i o no f s h i e l d e dw i r e { a ) .
. J a c kc o n n e c t i o ni s l o o s e .( b )
o Line cord or f luorescentlamo is near the s h i e l d e dw i r e . ( c )
o P o o r g r o u n d i n g .( d )
aH a m t r a n s m i t t i n gs t a t i o no r T V t r a n s m i t - t i n g s t a t i o ni s n e a ry o u r h o u s e .( e )
. S t y l u si s w o r n o u t . ( a )
. R e c o r di s w o r n o u t . ( b )
a Dust adheresto stvlus . (c)
. S t y l u si s i m p r o p e r l ym o u n t e d .( d )
aStylus pressureis not proper . (e) r T h e T R E B L E l e v e li s t o o h i q h .
R e v e r s i n gth e l i n e p l u g m a y o c c a s i o n a l l ya l l e v i a t et h i s n o i s ep r o b l e m .U s u a l l yi t i s v e r y d i f f i c u l t t o e l i m i n a t e t n e n o r s e .
lmpossibleto removesuch interference .lf the causeof such noise is in the TV set . increasethe distance betweenthe TV set and receiver .
I n a n a r e a s u r r o u n d e db y h i l l s o r h i g h b u i l d i n g s ,t h e F M i n p u t s i g n a l sa r e v e r y w e a k .T h u s t h e n o i s el i m i t e r i n t h e c i r c u i t l o s e si t s f u n c t i o n .S e t u p a n o u t d o o r F M antennahavingmany reflector elements .
I n c r e a s i n gF M i n p u t s i g n a lm a y a l l e v i a t eth i s p r o b l e m . Use an exclusive FM outdoor antenna insteadof the indoor T - tvpe antenna .
C o r r e c rt h e c o n d i t i o n ss t a t e di n ( a ) , ( b ) . ( c ) o r ( d ) . l n caseof (e), report it to an ofJicialactivity .
Check (a) through (e) and correct the condation .
L o w e r t h e T R E B L E l e v e l .
Watch for the following conditions;theseare alsoapt to be mistakenfor malfunction .
S y m p t o m
Power is not turned on although the power switch r ss e t t o O N .
I n p l a y i n g a r e c o r d , i n - creasingthe volume causes h o w l i n g .
SuspectedSourceof Noise
o Fuseblows . (a)
. L i n e p l u g i s l o o s e .( b )
a Distance between the turntable and the soeakersis too short .
aT h e p l a c e o n w h i c h t h e t u r n t a b l eo r soeakersare set is unstable .
D i a g n o s i sa n d R e m e d y
C h e c k ( a ) a n d ( b ) a n d c o r r e c t t h e c o n d i t i o n .
Change the distance or rearrange the installataon i n c r e a s eo f t h e u n i t a n d s p e a k e r s .( l n s t a l l i n gt h e
t u r n t a b l e o n a f i r m , s o l i d s t a n d m a y a l l e v i a t et h i s o r o b l e m . )
Do not enhancethe BASS sound levelexcessavely .
TZ
