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CA 3
ST B0 layout
B
R i g h t i n p u t
9
Left input
1 0 R i g h t o u t p u t
1 1 Lefi output
1 2 E a r t h
1 3 E a r t h , s i g n a l a n d -
11 !"rl \ o,,ou,
l 3 r r r g n r
t
C A 6
P o w e r s u p p l y
A l t h o u g h t h e p r e a m p w i l l f u n c t i o n o v e r t h e f u l l r a n g e 1 2 t o 3 5 V t h e
o v e r l o a d m a r g i n i s r e d u c e d a s t h e s u p p l y v o l t a g e d r o p s : a t 1 2 V t h e
m a x i m u m o u t p u t i s 1 V . R e p l a c i n g R 1 9 b y 1 K w i l l i n c r e a s e t h i s t o 2 V
r m s .
A b o v e 3 5 v o l t s C 1 6 ' s v o l t a g e b e c o m e s e x c e e d e d , w h i c h w i l l n o t
damage it until severe overload occurs. However it is best to fit an
additional resistor in series with pin 1 -- use 10K for 40
50 volts
and 22K for 50 - 70 volts.
CA7
Inputs and Outputs
C A 7 . 1 . M a g n e t i c a n d c e r a m i c p i c k u p s : V i r t u a l l y a l l m a g n e t i c p i c k u p s
w i l l f e e d d i r e c t l y i n t o t h e i n p u t w i t h P U 1 s e l e c t e d . T h e o n l y
e x c e p t i o n s a r e l o w i m p e d a n c e d e v i c e s , s u c h a s t h e O r t o f o n , w h i c h
n e e d a m a t c h i n g t r a n s f o r m e r . C e r a m i c s f e e d t h e i n p u t w i t h p U 2
s e l e c t e d .
T h e r e i s a c o n s i d e r a b l e v a r i a t i o n i n o u t p u t f r o m p i c k u p t o p i c k u p
s o s o m e o f t h e h i g h e r o u t p u t t y p e s m a y r e q u i r e a v e r y l o w v o l u m e
c o n t r o l s e t t r n g .
CA7.2. Flat inputs: radio and tape. The radio input has a sensitivity
of 100mV and the tape 30mV. Almost every signal source you may
wish to use will feed one or other of these inputs, but if you wish to
reduce the sensitivity of either one the alternator of CA 7.4. can be
u s e d .
C A 7 . 3 T a p e o u t p u t i s 3 0 m V . l t c a n n o t b e i n c r e a s e d , b u t s h o u l d
y o u w i s h t o r e d u c e i t t h e n t h e a t t e n u a t o r o f C A 7 . 4 c a n b e u s e d .
CA 7.4. attenuator. The figure shows a skeleton preset pot wired
w i t h s c r e e n e d l e a d s f o r i n p u t a n d o u t p u t . I n p u t l e a d i s f r o m t h e t u n e r
o r t a p e r e c o r d e r a n d o u t p u t l e a d f e e d s t o t h e p r e a m p l i f i e r ' s i n p u t _
Used on tape out, this feeds the attenuator's input and the
attenuator's output feeds the tape recorder's input. The preset can
b e a n y v a l u e b e t w e e n 1 0 K a n d 1 0 0 K , 2 2 K o r 4 7 K g e n e r a l l y b e i n g b e s t .
The preset should be adjusted for best results.
C A 8
M o n o U s e
l f a m o n o s o u r c e ( e . 9 . t u n e r w i t h o u t d e c o d e r , o r a m o n o l a p e
recorder) is used pins 5 & 6 or 8 I 9 can be joined together. Any
i n p u t f e d t o e i t h e r p i n w i l l t h e n b e a m p l i f i e d b v b o t h c h a n n e l s .
F o r r e c o r d i n g i n t o m o n o r e c o r d e r i t i s q u i t e p e r m i s s i b l e t o j o i n p i n s
1 0 a n d 1 1 t o g e t h e r , t h i s w i l l n o t a f f e c t t h e c h a n n e l s e o a r a t i o n
t h r o u g h t h e a m p l i f i e r i n n o r m a l u s e .
CA 7.4
Altenuator
I
t _
> I a p e I n p u t a n d o u t p u t c o n n e c t i o n s
l
J
ve power
1B
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