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1 5/1 6 ips: 1 ,000 cps - 40 c p s - 63 cps -
80 cps - 1 00 cps - 1 25 cps -
1 60 cps - 200 cps - 250 cps -
3 1 5 cps - 400 cps - 500 cps -
630 cps - 800 c p s - 1 ,000 cps -
1 ,250 cps - 1 ,600 cps - 2,000 cps
- 2,500 cps - 3,1 50 cps -
4,000 cps - 4,500 cps - 1 ,000 cps.
VTVM
C o n nect a
across the contacts
of the " Radio/Phone "' s ocket. P l ay back the
reco rded test frequencies. Read the output
voltages of the test frequencies.
5.4 Measuring t h e Recording Equalization
Th i s measurement must be made at all tape
speeds:
1 . S i m u ltaneously depress the reco rd i n g key
and the start key. The use of tape i s not
necessary.
2.
Connect a n a u d i o o s c i l lator across the
c ontacts 1 and 2 of the · Ra d i o/Phone "
socket and feed a s i g n a l of
1 0 m i l l ivolts.
3.
Connect a n a u d io-frequency VTVM across
the contacts 2 a n d 3 (3
=
· Accessori es " socket.
4.
Set the record i n g level contro l for f u l l
VTVM.
level and read t h e
the output volta g e of the a u d i o osc i l l ator
VTVM
u ntil the
reads 20 d b less.
5.
Feed the test frequencies perta i n i ng to the
se lected tape speed, as g iven i n para
5.3
graph
and compare the output voltages
with the corresponding va l u e s w h i ch a re
g iven on the back of the c i rc u i t d i agram.
The perm i s s i b l e deviations relative to the
d e s i red val ues is 1 .5 db. In case of g reater
deviations fi rst check the c i rc u i t voltages
of the amplifier and the components and
switch i ng c o ntacts of the e q u a l izer c i rcu it.
5.5 Meas uring the Playback Equal ization
Thi s mea s u rement must be made at a l l tape
speeds :
1 .
Cut the connection between the record
i n g/playback head and the p o s itive ter
m i n a l of the battery a n d i n s e rt a 1 0-ohm
resistor .
1 6
e n 2,4 cm/s : 1 000 Hz - 40 Hz - 63 Hz -
3
and 2
Brancher u n voltmetre electronique sur les
3
bornes
et 2 de l a prise · R a di o/Ph o n o • et
repro d u i re les frequences d e contro l e en
reg istrees. L i re l e s v a l eurs de tensions de
ces d ifferentes frequences.
5.4 Mesure d e la correction
l'enregistrement
Executer la mesure pour toutes les v i tesses
d e d efi lement:
1 . Enfoncer l e s touches · Enreg i strement• et
· Start• (! ' i nsert i o n d'une bande m a g neti
que n'est pas mkessa i re).
1
2. Brancher u n generateur B F aux bornes 1
,000 cps at
et
2
de la prise · Ra d i o/Ph o n o • et i njecter
une frequence d e 1 000 Hz/1 0 m
3 .
Raccorder u n voltmetre e lectron i q u e
gro u nd) of the
sur les bornes 2 et 3 (3
prise · Accesso i re s • .
T h e n reduce
4. Ajuster s u r la p l e i n e charge le regleur d u
n iveau d'enregistrement e t l i re l a ten s i o n
s u r le voltmetre e l ectronique BF. Redu ire
e n s u i te de 20 dB l a tension de sortie du
generate u r BF.
5. l njecter les frequences de controle affec
tees aux d i fferentes vitesses de defi l e
ment. L i re l e s v a l e u rs re spectives de l a
te nsion d e sortie e t l e s comparer avec l e s
valeurs n o m i n a l es i n d iquees a u verso d u
schema
±
1 ,5 d B . S i d e s ecarts p l u s importants
sont constate s , contro ler les ten s i o n s de
l ' a m p l i fi cate u r, ses composants, puis l e s
contacts de commutation du reseau c o r
recte ur.
5.5 Mesure d e la correction
(voir fig. 1 7)
Exec uter l a mesure p o u r toutes les vitesses
de defi lement:
1 . l nterc a l e r u n e res istance de couplage de
1 0 ohms dans l e fil pose entre l a tete
magnetique et l e pole
G�.>n.
+
1 7
F i g .
80 Hz - 1 00 Hz - 1 25 Hz -
1 60 Hz - 200 Hz - 250 Hz -
3 1 5 Hz - 400 Hz - 500 Hz -
630 Hz - 1 000 Hz - 1 250 Hz
1 250 Hz - 1 600 Hz - 2000 Hz
- 2500 Hz - 3 1 50 Hz -
4000 Hz - 4500 Hz - 1 000 Hz.
a
V.
masse) de la
=
de
c i rc u i t.
Ecart
admiss i b l e :
a
la lecture
+ .
4,7 cm . /se g . : 1 00 0 c./seg. - 40 c. / seg. -
63 c./seg. - 80 c . / s e g . -
1 00 c. / s e g . - 1 25 c. / s eg . -
1 60 c. / seg. - 200 c. / seg. -
250 c./seg. - 31 5 c. / seg. -
400 c ./ s e g
630 c. / s e g . - 800 c. / s e g . -
1 000 c
l s e g . - 1 250 c./seg.
.
- 1 600 c
- 2500 c . / s e g . - 3 1 50 c. / seg.
- 4000 c./seg. - 5000 c. /s e g
- 6300 c./seg. - 8000 c./ s e g .
- 1 0 000 c. / se g. - 1 000 c./
se g .
: 1 000 c. / seg. - 40 c. / seg. -
2,4 c m
/ s e g
.
.
63 c. / seg. - 80 c. / seg. -
1 00 c. / seg. - 1 25 c. / seg. -
1 60 c. / seg. - 200 c. / seg. -
250 c./seg. - 3 1 5 c. / seg. -
400 c. / seg. - 500 c. / seg. -
630 c . / seg. - 800 c. / seg. -
1 000 c. / seg. - 1 250 c./seg.
- 1 600 c . /s e g . - 2000 c. / s e g
- 2500 c. / seg. - 3 1 50 c. / seg.
- 4000 c . / se g . - 4500 c./seg.
- 1 000 c . / seg.
NF
Se conecta u n voltimetro d e valvula a I o s
contactos 3 y 2 del jack · Radio/Fono • . Se
reproducen l a s frec uencias de verific a c i 6 n
a ntes g rabadas. S e l e e n I o s valores d e l vol
taje de cada u n a de las fre c u e n c i a s de ve ri
ficac i 6 n .
5.4 Medicic:in d e la correcci c:i n d e grabacic:in
Efectuar la m e d i c i c:i n a todas las ve l o c i d ades
de c i nt a :
1 . Apretar l a s tec l a s · Grabac i 6 n • y · M ar
c h a · (no es necesaria la c i nta mag neto
f6nica).
2. Conectar e l generador de baja frec u e n c i a
a Ios co ntactos 1 y 2 d e l j a c k . R a d i o/Fono •
y dar u n a seiial de 1 000 c./seg. con 1 0 m
3.
Conectar e l voltimetro de valvula d e baja
frecuenc i a a Ios co ntactos
sa) del jack para aparatos a d i c ionales.
4.
G ra d u a r e l reg u l ador de modulac i 6 n a
modulaci6n maxi m a y leer e l voltaje en e l
voltimetro de valvula d e baja frecuenc i a .
A c o n t i n u a c i 6 n , d i s m i n u i r el voltaje d e
s a l i d a d e l generador de baja frec u e n c i a ,
h a sta q u e e l volti metro de valvu la i n d i q u e
2 0
dB menos.
5.
D a r s e ii a l e s con las frecuencias de veri
ficac i 6 n correspond i e ntes
las ve l o c i d ades de c i nta (vease para esto
e l ap artado 5.3) y comparar Ios voltajes
de s a l i d a c o n I o s valores n o m i n a l e s que
f i g uran a l dorso del esquema de conexio
n e s . D e sv i a c i 6 n tolerable de Ios valores
n o m i n a l e s
±
1 ,5 d B . S i e I a s desv i a c i o n e s
s o n mayore s . hay q u e revisar p r i m e ra
I o s
mente
voltajes d e f u n c i o n a m i e nto d e !
a m p l ificador, I o s e l e m e ntos componentes
corre s p o n d i entes, a s i coma Ios contactos
d e
c o n m utac i 6 n d e l c i rc u i to de correcc i 6 n
de la d i stors i 6 n .
5.5 Medicion d e la correcci6n de
reproduccic:in
Efectuar l a m e d i c i 6 n a todas las velocidades
de c i nta:
1 .
Conectar l a res i stanc i a d e acoplamiento
de 1 0 o h m i o s al cond uctor de l a cabeza
de sonido que va a l polo
- 500 c. / seg. -
.
/ s e g. - 2000 c . / seg.
.
.
.
V.
2
y 3 (3
ma
=
cada u n a d e
a
+
•
• .
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