OI
CONDITIONS
FREQUENTLY
MISTAKENFORTROUBLES
Noise:
Therear€
avarietyof noises
relatingto the operation
of
a hi-fi uni1.
Th€seare
g€nerally
dividedinto two types;
(1) rhe
unit is faulw (a transistoror part is deteriorated)and {2) an
externallource of noise
gives
noiseto the unit.
When
a hi-fi unit produces
anunpleasant
noise,
it isottenludged
that the unit is laulty, but statisticalrecordsindicate
that the
majorityot noises
produced
io hi-fi acoustic
units resllt from
external
sourci€sot noie. Due to the inherent
high lensitivity
and rhe high lideliry in reproduction,the unit amplifiesand
reproducesextranaous
nois€s,howe\rers.nall,into definits out-
put noise.lf your receiver
produces
a noise,checkaccording
to the tollowing table and tracr oul the sourceof nois6
for
anappropriato
correctiveaction.
Tho table includesthe condilions that mav be mistaken
lor
troublesoltheunit.
suspectgd Sourca of Noise Diagnosis and Remedy
6
to
c
j
3
Continuous or intermitt€nt
noi* like jjjill or zzzzzz- . Ststics or list6nin9.
a Fluoresc€nt lamp, motor, or thermostat
may b€ us€d in hous€ or in th€ vicinity
In many cas€s,
it is vory difficult to rsmov€ ths sou.c€
oi noiss. In ord€r to incroar€ th6 radio input la.g€. than
th€ nois€ lav€|, set up a good outdoor antonna and
make a compl6t€ grounding.
When a station is tuned
in, hum is mixod in tho
Program.
. Poor fluor€sc€nt lamp, motor, or slsciric
hsater mav b€ us€d in hous€ or neal lh€ Rsvgrslng th6 lin€ plug m6y occäsion.lly allwiat€ rhis
nois€ probl€m. usually lt Is vsry dlfficult to sliminsts
Hi$ing soundnoisein AM
{modium wavel rscsptlon. aTh€ fr€quoncy of 6n adjacsnt station is
interferlng wlth that of th6 srätlon bsing
tun€d in (1OkHz
bsat interfsrsnce).
. TV set is on in the samo house where
th€ receivor,
lmDossible to rsmovs such intsrter€nco. ll th6 caua6ol
such nols€ is in th€ TV sst. increase th€ distance
betw€€n the TV s6t and r6coiv6r,
Static noisoin FM roc€ption
{in particular. when 6uto-
moblles run clos€ to the
hous6l.
. Whit€ nois€s g€n€ratsd Jrom automobils
6ngin6s.
. Fadio fr€qu6ncv .ewing machins o. weld-
ing machlne b€lng us€d n€sr your hous€
In an area surrouncl€d by hllls or hlgh buildings, the
FM input signäls are very we€k. Thus ths nois€ limiter
in th€ ci.cuit los€sits function. S€t up an outdoor FM
antenna h6ving many r€tlector €lsmsnts.
IE
3
R€ceptlon of FM n€r6o
pJogtam contains morc
noi.€ than FM mono
a Nots that ths s€wlcs ar€a cov€red by an
FM sterco broadcast ls sbout 50 ', of
that ot a regular mono bro6dcast.
lncrsaslng FM Input signal may all€viate this problem.
Use 6n erclusiv€ FM outdoor antonna inst€ad of the
lndoor T-än1enna,
Hum o. buzz. Wh€n
swiichsd lo racliorscsptionr
ths nolss wlll disappear.
. Poor connsctlon of shieldodwl.6 (a).
. J6ck connsctlon is loos€. (b)
. Llne cord o. fluo.€:cont lamp is near thg
shi€ldad wl.s.(c)
. Poo. grounding.
{d)
a HAM ü6nsmltting nation or TV transtnit-
ting station i3nasr your hout€. (€)
corrrct the condition. .tat6d in (6), (b), {c) or {d}.
In cas€of (6), r6po.t it to an official activity.
Output tone quality is poor
and mixed with noii€,
Trcbl6 13not cl6ar.
. Stylus is worn out. {a}
. R€co.d ls worn out. (bl
. Dust adherei to stylus. lcl
.lmpropsr mounting ot stylus. (d)
a Stvlus pr€ssur€ ls not ptopsr. (€)
. The TR€BLE sound lav6lis
too high.
Ch€ck (a) through (e) and cor.sct ths condition.
Low€r the TR EBLE l€vei.
Further,watchthe followingconditions:
Thesearealsoapt to bemistakenfor troubles
of the unit.
Symptom su3poctod sourcs of Nois€ Dlagnosis änd Rsmsdy
Pow€a 13not tuhod on al-
though tho powor 3witch is
s6tto oN.
. Fuss is blo$rn. {a}
. Lln€
plus
is
loo.€.
(b) Checkla) and
(bl andcorr€rct
thecondition,
In playing
8.gcoJd,
incree
ing ths volums will caus6
howling.
a Distanco b€hiroon ths Jecord plavsr and
the soeakers is too short.
aTh6 plece on whlch th€ rscord play€r oa
soeakers are set rs unstable.
Change ihe distance or r€arrang€tha installation po3lt-
ions ot tha unit änd sp€sk€rs. {lnstalling th6 r€cord
playor on € farm, solid sland may all€viate thls probl€m.)
Do nor enhancs ths BASS .ound lsv€l 6rcos.ivolv.