The Equalizing Amplifier In Amplifier Position - TANDBERG 12 Service Manual

Tape recorder
Table of Contents

Advertisement

3 0
d B
2 0 H z
5 0
5 . 1 . 5 T h e e q u a l i z i n g a m p l i f i e r i n A M P U F I E R p o s i t i o n
T h e e q u a l i z i n g a m p l i f i e r i n a m p l i f i e r p o s i t i o n i s
s h o w n i n f i g . 4 6 . A n e g a t i v e f e e d b a c k c i r c u i t i s c o n -
n e c t e d f r o m t h e e m i t t e r o f Q l 0 9 t o t h e e m i f t e r o f
Q l 0 7
w h i c h d e c r e a s e s t h e a m p l i f i c a t i o n a p p r o x .
10000
20000
3 4 d B . C l 3 l i s i n t r o d u c e d t o p r e v e n t t r a n s i e n t o s c i l -
l a t i o n s i n t h e t r a n s i s t o r Q 1 0 9 .
T h e s i g n a l i s f e d t o t h e p o w e r a m p l i f i e r v i a t h e s w i t c h
A l 3 . T h e f r e q u e n c y r e s p o n s e o f t h e e q u a l i z i n g a m p l i -
f i e r i n A M P L I F I E R p o s i t i o n i s f l a t w i t h i n t h e a u d i o
r a n 9 e .
100
200
500
1000
2000
s000
F i g . 4 5 . T h e r e s p o n s e c u r v e s f o r t h e e q u o l i z i n g o m p l i f i e r i n p l o y b o c k p o s i t i o n .
+
+ 2 7 \
R 1 4 1
220K
* n r a e
1 3 0
L
I J q
c 1 8 2
2 5 p
R 128
1 0 K
a
c 1 3 0
2,5 ]-t
6
1
o
B C l
7 l
R 1 4 6
To power
o m p .
c 1 8 1
4op
R 1 3 0
1 0 K
R 1 / . 7
1 K
R 1 4 4
1 K
c 1 3 5 r
1 0 n E
c 1 1 9
Q 1 t ,
R 2 0 1
6 8 K
R ' r 2 5
6 2 0
R 129
1 K
I
J %
J
\
\-..--
/z
x R r 2 o t , z r
1 2 1 Q B } P
+
2 5 V
80 tr
25Y
Q 109
BC 107V
R 1 2 3 5 , 1 M
From
=
volumeH
c o n t r o l
t
-I
:
F i g . 4 6 . T h e e q u o l i z i n g o m p l i f i e r i n o m p l i f i e r p o s i l i o n . s c h e m q t i c ,

Hide quick links:

Advertisement

Table of Contents
loading

Table of Contents