Seeburg 7800, Руководство по обслуживанию

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Servic&
Manual •41 Models
7800, 7850, 8800
and 9800
to establish credit in the
selector mechanism,
(�)
convey
selections to and establish them
on the solenoid drum i:lnd
(5)
to
cancel the credit established in
the electrical selector when a
selection is made. In addition,
there are some secondary func­
tions performed !.n the electrical
selector w"t.ich are necessary to
prevent cheating and possible
m i
st
re a tm
e
n t
or
overloading of
parts designed for momentary duty
only.
T�e function of the comp<r
nents in th� electrical selector
�ill be discussed by considering
the circuits involved. ·To sim­
plify the following discussion,
reference will be made almost
entirely to the Type C selecl..o:r.
The explanaticns may be applied
unchanged to analysis of the Typ�
B
selector operatlon.
B. C O I N OR CREDIT CIRClJIT
The Coin Switch Assembly in
the Symphonola operates in c
o
� ­
with the credit magnet
24, I1'.em
17;
Fig.
19,
Item.
M4)
of the E l ec t ric a l Selector to
establish credit on �he ratchet
wheel
(
Fig. �4, l tern
9)
•
Each
time a coin closes one of the
contacts L, the Coin Switch As­
the ratchet escape�ent
lever
24,
Item 13)
is op­
erated by vhe credit magnet and
allows one tooth on the ratchet
wheel to �scape, rotating the
ra{;chet wheel through an angle
eQuivalent to one tooth.
C. SF.L�C TOR SW! TCB
'!:he selector switches permit
the
operator to make the selec­
tion desired.
It is so c o n ­
structe<l that ir. is impossible to
excite Uro selection solenoids at
6
once. There are two fundamental
circuits
tlirough
the selector
switches as shown on the Sche­
matic diagi;em
(
Fig.
19);
these
are the red circuit and the black
circuit as labeled. The red
circuit is comoleted to the sole­
noid
drum
when a selector button
is pressed. The black circuit
permits i:;he Jnterlocking relay
to function after the credit can­
cel solenoid has operated. The
r�lationsllip of
the switch seg­
ments is such that the black
circuit is closed before the red
circuit is completed. The red
circuit is not
closed
but is left
open
when two or more selector
buttons are pushed simultaneously.
I. study of the Schematic Diagram
(
Fig.
1.9)
will show how this hap­
pens.
The purpose and the
im­
portance of th:ls will be ex­
plained as other parts of the
electrical selector are dis­
cussed.
D. SERif:S RRLJ:.Y CIRCUIT
Wnen �he credit switch con­
tacts of the credit switch
(
F·ig.
24,
!te10 24; Fig.
19,
Item M3)
a1'e closed and the customer
pushes a selector button, the
series circuit is completed
through the series relay to the
corresponding selection solenoid
on the solenoid drum. The credit
circuit contacts are those near­
est the front of the Credit
Switch.
When t h e series circuit
is completed, the series relay
contacts close and i:l. selector pin
is pushed up on the solenoid
drum.
F. CP..NCEL SOLENOID CIRCuIT
The cancel
solenoid
circuit
is com�leted through the cancel.
solenoid
(Fig.
24,
Item 2; F i
g
.
19,
I
tern :Ml
)
when the large con-
r