1 . T h e S i gn a l t o N o i s e o f F m a t m o d u l a t i on i n d e x = 5 i s f a c t or of S /N of A M ( a) 7 5 ( b ) 5 7 ( c ) 8 1 ( d ) 7 0
2 . T h e S i gn a l t o N o i s e r a t i o of V S B - S C s ch e m e i s ( a) 2 ( b ) 1 ( c ) 3 ( d ) z e r o
3 . I n P M , t h e p owe r s p e c t r a l d e n s i ty o f t h e O/ P n o i s e , va r i e s w i th f r e q u e n c y a s ( a) c i r c l e ( b ) Pa ra b o l a ( c ) H y p e r b o l a ( d ) U n i f o r m
4 . T h e S N R of P M ove r A M i s o f B W o f Tr an s m i s s i on ( a) s q u a re ( b ) d o u b l e ( c ) q u ad r u p l e ( d ) S a m e
5 . B r o ad c as t tr a n s m i t te rs a re d e s i g n e d f or t r a n s m i t ti n g ( a) S p e e ch or mu s i c ( b ) C o d e d s i gn a l ( c ) C o nti nu o u s c a r r i e r ( d ) Te l e p h on e s i g n al
6 . M i c r owave t r an s m i t t e r s h ave t h e i r wo r ki n g f re qu e nc i e s a t a r e a b o u t ( a) 1 00 0M H z ( b ) 1 00 M H z ( c ) 1 0M H z ( d ) 8 0 M H z
7 . B o o s t i n g h i gh f r e q u e n c y c o m p o n e nts i n m o d u l a ti n g s i gn a l i s c a l l e d ( a) At te nu a t i n g ( b ) E ch o s u p p r e s s i n g ( c ) Ton e f o rr e c t i o n ( d ) p r e e m p h a s i s
8 . M o s t o f t h e p owe r i n A M s i gn a l l i e s i n i ts ( a) C a r ri e r ( b ) U S B ( c ) B o t h U S B a n d L S B ( d ) L S B
9 . A p u s h p u l l p owe r a m p l i fi e r t h a t i s u s e d f o r c a r ri e r s u p p r e s s i o n i s c a l l e d ( a) H o rm o n i c ge n e r a t or ( b ) B a l a n c e d m o d u l a to r ( c ) Fr e q u e n c y m i xe r ( d ) Fr e q u e n c y mu l t i p l i e r
1 0. T h e ab i l i ty o f a r e c e i ve r to r e s p on d to t h e we ake s t s i gn a l i s c a l l e d ( a) S i g n al h an d l i n g a b i l i ty ( b ) S e n s i t i v i ty ( c ) fi d e l i ty ( d ) s e l e c t i vi ty
1 1. A l l c om m e r c i a l r e c e i ve r s e m p l oy I F b e twe e n ( a) 2 00 t o 3 00 K H z ( b ) 1 2 to 1 3 K H ( c ) 4 55 t o 4 65 K H z ( d ) 7 40 t o 8 40 K H z
1 2. T h e nu mb e r of m i x e r s t a ge s o f a t r i p l e d e te c t i on r e c e i ve r ( a) 2 ( b ) 1 ( c ) 4 ( d ) 3
1 3. S e l e c ti v i ty of a r e c e i ve r i s d e p e n d e nt on ( a) m i x e r ( b ) m i x e r a n d I F ( c ) I F am p l i fi e r ( d ) R F & M i x e r
1 4. I n d i c a t e w h i ch on e o f t h e f ol l ow i n g b l o cks i s u s e d i n b ot h c om mu n i c a t i on re c e i ve r s a n d b r oa d c a s t r e c e i ve r s ( a) m i x e r ( b ) L i m i t e r ( c ) b e a t f r e q u e n c y os c i l l at o r ( d ) S q u e l ch
1 5. I n a s u p e r h e te ro d y n e r e c e i ve r ( a) L o c al Os c i l l at o r f r e q u e n c y i s d o ub l e I F ( b ) T h e ou t p u t c i r c u i t of m i xe r i s t u n e d t o s i gn a l f r e q u e n c y ( c ) L o c al os c i l l at o r f r e q u e n c y i s g re at e r t h a n i n c o m i n g s i gn a l f re qu e n c y ( d ) R F wo rk s at 45 5 K H z
1 6. T h e m i n i mu m ch an n e l b an d w i d t h r e q u i r e d f o r t r an s m i tt i n g 3 b a s e b a n d s i g n al s , e a ch i s b an d l i m i te d t o 3 K H z ( a) 3 K H z ( b ) 1 . 5 K H ( c ) 6 K H z ( d ) 9 K H z
1 7. I n d i c a t e t h e f al s e s ta t e m e nt : I f t h e I nt e r m e d i a t e f r e q u e n c y i s h i g h ( a) t h e l o c a l o s c i l l a t or n e e d n o t b e h i gh l y s ta b l e ( b ) i m a ge f r e q u e n c y r e j e c t i on i s ve r y go o d ( c ) t ack i n g w i l l b e i m p r ove d ( d ) t h e s e l e c t i v i ty w i l l b e p o or
1 8. W h i ch f u n c t i on a l b l o ck r e a d i ly i d e nti fi e s i t i s a n F M re c e i ve r ( a) I F am p ( b ) R F a m p ( c ) d e t e c t o r ( d ) m i x e r
1 9. AG C fi l te r u s e s n or m a l l y t h e val u e s o f R = 5 00 K a nd C e qu a l t o ( a) 1 µF ( b ) 2 0 µF ( c ) 2 µF ( d ) 1 0 µF
2 0. Q u ant i s i n g n oi s e i n a P C M s y s t e m c a n b e r e d u c e d by ( a) D e c r e a s i n g t h e nu mb e r o f s t an d a rd l e ve l s ( b ) I n c r e a s i n g t h e nu mb e r of s t an d a r d l e ve l s ( c ) U s i n g l ow n o i s e c i rc u i tr y i n P C M r e c e i ve r ( d ) H av i n g m o r e n o . of s a m p l e s p e r s e c on d
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