Kenwood RA-920 Instruction Manual page 9

APPLICATIONS
2 . M e a s u r e m e n t o f p u l s e c i r c u i t t h r e s h o l d level ( F i g . 4 )
1) A d j u s t t h e v o l t a g e o f pulse c i r c u i t t o a p r o p e r level
(5-1OV f o r T T L ) , t h e n set R A - 9 2 0 t o 0 d B .
2) A d j u s t R A - 9 2 0 so t h a t t h e o u t p u t disappears f r o m t h e
o s c i l l o s c o p e !
3) W h e r e t h e r e a d i n g o f R A - 9 2 0 is 5 , t h e t h r e s h o l d level
is e , a n d t h e pulse g e n e r a t o r o u t p u t is e j ,
Q
e = e L O G
- 1
0 j X
In m e a s u r e m e n t , be sure t h a t t h e pulse f r e q u e n c y is
b e l o w 1 0 0 k H z , t h e signal is p r o p e r l y s h e i l d e d a n d
t h e l o a d i m p e d a n c e is a d e q u a t e .
Pulse
RA-920
generator
Oscilloscope
60on
Pulse
circu it
F i g . 4
3. A u d i o m i x i n g ( F i g . 5 )
B y using t w o R A - 9 2 0 , it is possible t o a t t e n u a t e t w o
i n d i v i d u a l signals f o r a u d i o m i x i n g .
MIC
amplifier
T R I G
Tape
RA-920
recorder
Speaker
RA-920
Mixing
amplifier
amplifier
Speaker
F i g . 5
Main
9