
No. 52003
V-36F70
V-36F71
V-36F80
3
SAFETY PRECAUTIONS
1. The d esign of t hi s p ro du ct c ont ains spec i al h ar dwar e, m an y
circu it s a nd co mp on ent s s pecial ly for saf ety pur p oses. For
continued protection, no changes should be made to the
or igina l des ig n u nless a uth or ized in wri ti ng by t he man uf actu re r.
Rep lacem en t par ts m ust be i d ent ic al t o t hos e u sed in th e
or igina l cir cuit s. S er vic e sho ul d be per f or me d b y qu al ified
p ers onn el o nl y.
2. Al te r ation s of th e desig n o r circu itr y of th e p rodu cts s hou l d n ot
b e m ad e. A ny de sign alte ra tions o r ad ditio ns wi ll vo id th e
manufacturer's warranty and will further relieve the
m anu fact ur er of r esp ons ib ilit y f or pe rs ona l in ju r y or p rope rt y
d am age r esu lt in g t her ef r om .
3. M an y e l ectr ical an d m ech an ic al pa rt s in th e p rodu cts h ave
sp ecial saf ety-r elat ed c har act eris tics. Th ese charac teristics are
oft en n ot e vi d en t fr om visu al in spe ction no r can t he pr ote ction
aff or de d by th em n ecess aril y be o bta in ed b y usi ng
r eplac em ent co mp on ent s ra ted for h ig her vo ltag e, w a ttag e, etc.
Rep lacem en t pa rt s wh ic h h ave t hes e sp ecial s afet y
ch ar acter istics a re i d entifi e d in th e par ts list of S ervice m an ua l.
Electrical components having such featur es are identified
by shading on the schematics and by (!
!!
!) on the parts list
in S ervice manual . Th e u se of a su bst itu te re plac em en t whi ch
does not have the same saf ety charact eristics as the
r eco mm en de d re plac em en t pa rt sho wn i n the pa rts l ist of
Se rvice ma nu al may c aus e sh ock, f ir e, or o th er haz ards.
4. Use iso la t ion tr an sforme r when hot c hass is .
The chassis and any sub-chassis contained in some products
ar e c on nect ed to on e si de of th e AC p ow er l ine . An i sola tion
tr ansf or m er of ad equ ate cap aci ty sh ou ld be inser t ed bet we en
th e p r odu ct and t he AC p ower su pp ly p oi nt w hil e p er for ming
an y ser vice on so me pr o ducts wh en th e HOT ch assis i s
exp ose d.
5. Do n't short between the LIVE side ground and ISOLATED
(NEUTRAL) side ground or EARTH side ground when
repairing.
So m e m od el's p ow er c ir cuit is par t ly di f feren t in t he GND . Th e
diff er enc e of t he GND is sh own by th e LI VE : (") side GND,
th e ISO LATED( NEUTRA L) : (#) sid e GND an d EARTH : ( $)
side GND . Don 't sho rt be tw ee n t he LIVE sid e GN D a nd
ISO LATE D(NEUTRAL) side GND or EARTH side GND a nd
never measure with a meas uring apparatus (oscilloscope etc.)
th e LI VE side GND a nd ISO LATED(NEUTRA L) sid e G ND or
EARTH side GND at the s ame time.
If above note will not be kept, a fuse or any parts will be brok en.
6. If an y re pa ir h as b ee n m ad e to th e ch assi s, it is re comm end ed
th at t he B1 se ttin g sh ou ld b e chec ked or ad juste d (S ee
ADJUSTMENT OF B 1 POW E R SUPPL Y).
7. The hi g h vol t ag e a pp lied t o th e pictu re tu be mu st co nfo rm with
that specified in Service manual. Excessive high voltage can
cau se an i ncr ea se in X-Ra y em issi on , a rcin g and p ossi ble
com po ne nt d am ag e, th eref or e op er atio n un der excess ive hi gh
volta ge c ond it i ons sh ou ld be ke pt to a m in imu m, or sh ou l d be
pr eve nt ed. I f seve re arc in g occu rs, r emove th e AC p ow er
immediately and determine the cause by visual inspection
( in cor r ect insta lla tion , cr ac ked o r m elte d hi gh voltag e h ar ness,
p oor s ol de ri n g, etc. ). T o ma in ta in the pr op er minim um le vel of
soft X-Ray emission, components in the high voltage circuitry
includ ing the pictu re tu be mu st be the exa ct rep l acemen ts or
alte rn at i ves a ppr o ved b y th e ma nuf actu rer of th e co mp lete
pr od uct.
11 . D o n ot c hec k hi gh volta ge by d rawin g a n ar c. U s e a high
volta ge m ete r or a h i gh vol t age p ro be w ith a VTVM. Di sch ar ge
th e p ictu r e tu be bef or e a tte mp ti ng me ter co nne ction , b y
con nec ting a clip lead t o th e grou nd frame a nd con n ecting t he
oth er e nd of t he l ead th r oug h a 10 kΩ2W resist or to t he ano de
bu tto n.
9. W hen se rvi ce is r equ ir ed, ob ser ve th e o ri g in al lea d dr ess.
Extr a p r ecau ti on sh ou l d be given t o assu r e cor re ct lea d dr es s
in the h i gh volta ge c ircu it area . W her e a sh ort ci rcui t ha s
occu rre d, th ose c omp on en ts th at ind ic ate evi den ce of
overheating should be replaced. Always use the
m anu fact ur er 's r eplace m ent com p on ents.
10 . Isolation Check
(Safety for Electrical Shock Hazard)
Af ter r e- a ssem bli ng th e pr od uct , al ways pe rf or m an i so l ati on
ch eck on th e expo sed m eta l p ar ts of th e c abi n et ( ant en na
ter m ina ls, vi de o/a ud i o in pu t and out put t er min als, Con trol
knobs, metal cabinet, screwheads, earphone jack, control
sh afts, etc.) to be sur e th e pr o duct is saf e t o op er at e w ith out
d ang er of elect rica l shoc k.
(1) Dielectric Strength Test
The is ol at io n b etw e en the AC pr ima ry cir cu it and al l meta l par ts
exp ose d t o th e us er , part icu lar ly an y expo sed m etal p ar t h aving
a return pat h to the ch assis sh ou ld withst and a volta ge of
11 00V AC ( r .m .s.) f or a p er iod of on e sec ond .
(. . . . Withs tand a voltage of 1100V A C (r.m. s.) to an appliance
r ate d up to 1 20V , a nd 3 00 0V AC (r .m. s.) t o an ap pl ianc e r a ted
200V or more, for a periodof one second.)
Thi s m eth od of test r e qu ir es a t est eq ui p me nt n ot g en er all y
fou nd i n t he ser vice t ra de.
(2) Leakage Current Check
Plug t he A C line c or d dir ect ly int o th e AC outlet (do not use a
lin e is ol ati on tra nsf ormer dur ing t hi s che ck.) . U sing a "L eaka ge
Cur rent Test er ", m ea sure t he l ea kag e cur r en t fr om each
exp ose d meta l par t of th e ca bi ne t, p ar tic ular ly an y expo sed
metal part having a return path to the ch assis , to a kn own good
ea rt h gr o und ( wa ter p ipe, etc.) . A ny l ea kag e cur ren t m ust not
exce ed 0. 5m A AC (r.m. s.).
Howeve r, i n t ro pical a r ea, this m ust no t e xc eed 0 .2m A AC
(r.m.s. ).
"
""
"Alte rnat e Che ck M ethod
Plug t he A C line c or d dir ect ly int o th e AC outlet (do not use a
line isolation transformer during this check.). Use an AC
voltmet er h aving 100 0 o hm s per volt or m or e sen si ti vit y in the
fol lo win g ma nne r. Con nec t a 1 50 0Ω1 0W r esistor pa ra ll e led
by a 0.15μF AC- typ e cap aci tor b etw e en an exp ose d m eta l
p art an d a kno wn g o od ear th gr ou nd ( wate r pip e, et c.).
M easu r e th e A C vo l tag e acr oss th e r esist or wit h t he AC
voltmet er. Move the res ist or connection to each exposed metal
part, particularly any exposed metalpart having a return path to
th e ch assis , an d m ea sure t he A C volta ge acr oss th e r esisto r.
Now, r eve rs e th e pl u g in t he A C out let a nd rep e at e ach
m easu r em en t. An y volta ge me asu re d m ust not exce ed 0.7 5V
AC (r.m. s.) . This corresp onds t o 0.5 mA A C (r.m. s.).
Howeve r, i n tr op ic al ar ea, this m ust n ot excee d 0 .3V AC
(r.m.s. ). This corresp onds t o 0.2mA A C (r.m .s.).
0.15μF AC-T YP E
1500Ω10W
GOOD
EARTH
GR OUND
PLACE THIS PROBE
ON E A C H EX PO SE D
ME T AL PA RT
ACVOLTMETER
(HAVING 1000 Ω/V,
OR MOR E SENSIT IVITY)
11 . High voltage hold down circuit check.
Af ter r ep air of th e high volt ag e h ol d d own ci rcui t, th is ci rcu it
sh all b e c hec ked to op er ate cor r ectly.
See ite m "Ho w to check the high voltage hold down
cir cuit".
A V
This mark shows a fast
operating fuse, the
letters indicated below
show the rating.