ESI VideoBridge 2150, Руководство по обслуживанию

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3 . 5 . 3 Ve r t i ca l D r i ve
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F i gure 3 -1 9 . Ver t i ca l D r i ve
T h e V e r t i c a l S y n c s i g n a l c o m e s i n o n p i n 4 o f P 3 0 1 a n d i s f e d t o
i n ve r t e r Q 5 . Amp l i f i e r U l i s the a c t i v e e l eme n t f o r t h e ve r t i ca l
saw t o o t h g e n e ra t or . T h e ve r t i ca l s a w t o o t h g e ne ra t o r tra n s f o rms t h e se
ve r t i c a l syn c i npu t pu l s e s i n t o a l i ne a r , s aw to o t h v o l t a g e w a v e f orm
t h a t w i l l e v e n tua l l y d r i v e t h e ve rt i ca l de f l e c t i o n yok e .
T he saw too t h
g e n e ra t o r ope r a t e s a s f o l l ow s :
D u r i ng t h e po s i t i ve po r t i on o f t h e v e r t i ca l sync s i g na l , i n v e r t e r Q 5
i s t u r ne d on p u l l i n g i t s o u t pu t l ow . T h i s p r o v i d e s a nea r g round
s i g n a l to t h e i n pu t r e s i s t o r of U l ( R 1 3 ) c a u s i n g t h e f e e d ba c k
c a p a c i t o r C 4 t o c ha r g e i n a po s i t i v e d i r e c t i o n .
C a p a c i t o r C 4 ,
r e s i s t o r R 1 3 , a n d t h e v o l t a g e a c r o s s R 1 3 d e f i n e t h e s l o p e o f t h e
r i s i ng ou t pu t .
Du r i ng t h e l ow l e ve l o f t he ve r t i c a l s y n c s i gna l ,
i n ve r t e r Q 5 i s turned o f f w i t h i t s ou tpu t p u l l e d t o + 1 5 V D C b y pu l l -u p
r e s i s t o r R 8 . T h i s p r o v i d e s a po s i t i ve s i g na l to t he i n v e r t i ng i npu t
o f U l ca u s i n g t h e f e e dba c k capa c i t o r C 4 t o d i s c ha r g e ba c k to z e r o .
T h e d i s c h a r g e r a t e i s m u c h f a s t e r t h a n t h e c h a r g e ra t e d u e to t h e
a c t i on o f d i ode C R 2 w h i ch i s f o rwa rd b i a s e d du r i n g t h e l ow l e ve l o f
t h e v e r t i c a l s y n c p u l s e , y i e l d i n g a s l o p e m u c h g r e a t e r t h a n t h a t
dur i n g t he p o s i t i ve pa r t s i n c e R 1 3 i s bypa s s e d d u r i ng t h i s c y c l e .
e / s / i
3 - 3 1
2 1 5 0 / 2 1 6 0 5 /8 5