GE K-49861
The SP ca r d comb i nes
the previou s l y me n t ioned quan t i t i e s
to
p roduce var ious ou tput s i g na l s wh i ch are then f ed a s i npu t s to o t h e r
ca r d s .
Tabl e VIII i nd i ca t es t h e t ypes o f ou tpu t s i gna l s p roduced b y
the S P ca r d and wh i ch oth e r c a r d s a r e f ed b y each s i g nal .
The comb i ned pola r i z i ng ( CP ) card p roduces vol ta g e s, VAs + 0 . 3
VAal, V8c + 0 . 3 Vsc1 and VcA + 0 . 3 VeAl by a l g ebr a i c s umma t ions o f VAs'
V8c, and VcA·
The se vol tages a r e then f i l t e r ed i n a c t i ve bandpa s s
f i l t e r s w i t h na t u r a l f r equ enc i e s ( fo ) equal t o the s y s t em f r equency .
The t h r ee f i l t e r ed vol tages a r e fed to the CL c a r d a s pol a r i z i ng
qua n t i t i e s .
The ope r a t e s i g na l ( OS ) card f i l t e r s i t s i nput s i g na l s f rom t h e
S P ca r d i n a c t i v e bandpa s s f i l t e r s w i t h na t u r a l f r equenc i e s equ a l to
s y s t em
f r equency .
C i r c u i t r y
is
a l so
p r o v i ded
to
bypa s s
t h i s
f i l t e r i ng for ( IZ -TV ) s i g na l s o f l a r ge mag n i tude s .
The o u t pu t s o f
the OS ca r d a r e f ed to the ( CL ) card a s ope r a t ing s i g n a l s .
Each pha s e of the CL card has t h r ee i npu t s i gna l s and p rodu c e s a
h i gh log i c ( + 15 vol t s DC ) ou tput s i gnal whenever t h e s e s i g na l s have
the p rope r
i n s t an taneou s pha s e r e l a t ionsh ip .
Tabl e IX s hows t h e
va r ious
i npu t
s i gna l s
f o r
pha s e AB
and
whe r e
the
s i gna l s a r e
obt a i ned .
In o r d e r for the outpu t of CL to be h i g h, i npu t s 1 and 3
mu s t have the same pola r i t y and i nput
2 mu s t have an oppo s i t e
pol a r i t y .
INPUT NO.
1
2
3
TABLE IX
INPUTS TO CL CARD
INPUT SIGNAL
Quadrature Polarizing
Operate Signal
(IA - Is)ZRl
DERIVED FROM
QP Card
OS Card
SP Card
The CL ca r d output s a r e fed to the i n t eg r a t i ng t ime r ( IT ) ca r d
wh i ch mea s u r e the t ime that each CL outpu t s i g nal i s h i gh .
I f the
i nput s i gnal to the IT card is h i gh for 4 . 1 6 m i l l i s econds ( 5 0 h e r t z
r e lays - 5 . 0 m i l l i s e conds ) on a repe t i t i ve bas i s ( or 5 . 5 m i l l i s e conds
( 5 0 he r t z r e l ay s - 6 . 6 m i l l i seconds )
on a s i ng l e s hot ba s i s ) , t h e
ou tpu t of the I T card w i l l g o to a h i gh log i c va lue wh i ch p i c k s up a
r e e d r e l a y ( Kl ) mounted on the powe r supply ( PS ) ca r d .
A norma l l y
ope n con t a c t on Kl ene r g i z e s a t e l ephone r e l a y ( K 2 ) moun t e d on the
f ront pa ne l .
Two no rma l l y open contac t s of K 2 are conne c t ed
i n
s e r i es
w i t h the co i l s o f t a r g e t s t o p rov ide
the ma i n t r i pp i ng
con t a c t s ( 1 1 t h rough 1 4 and 18 ) .
In add i t ion, a th i rd no rma l l y open
con t a c t of K2 i s connec t ed between t e rm i na l s 19 and 9 w i tho u t a
t a r g e t for aux i l i a r y f u nct ions .
The i npu t DC con t rol powe r ( 48, 1 1 0, o r 1 25 vol t s ) i s conne c t ed
to the pow e r suppl y ( PS ) card wh i ch conta i ns a DC- to-DC conve r t e r .
The ou tputs o f the DC- to-DC conve r t e r a r e ± 15 vol t s DC r eg u l a t ed
wh i ch s upply the neces s a r y cont rol power to the o t h e r c a r d s .
The
t r a n s forme r in the DC- to-DC conve r t e r prov i de s i so l a t ion between t h e
12
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