IVIE IE-10A, Руководство владельца и оператора

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There i s no upper i m i t t o measuring l a r g e voltages w i t h t h e
p r o v i d i n g a arge enough a t t e n u a t o r i s a v a i l a b l e . With t h e o p t i o n a l
51AD adaptor and a 10: 1 o s c i l l o s c o p e d i v i d e r probe, t h e can
measure up t o 218.3 v o l t s o v e r t h e frequency range o f 25
Hz t o 20 KHz. The e x c e l l e n t i s o l a t i o n of t h e w i l l a l l o w t h e
measurement of power i n e v o l tages and wi
,
i n a d d i t i o n , d i s p l a y t h e
octave frequency o f t h e ne. One thousand vol t s AC o r DC can be appl i e d
d i r e c t l y t o t h e e x t e r n a l i n p u t o f t h e w i t h o u t c i r c u i t damage.
Using e x t e r n a l a t t e n u a t o r s , t h i s damage l i m i t can be extended
above
one thousand vol t s .
The s m a l l e s t v o l t a g e t h a t can be measured on t h e i s determined by
t h e n o i s e f l o o r o f t h e a n a l y z e r . I n F I G . 3 1 t h e t y p i c a l n o i s e f l o o r of
t h e i s shown t o be equal t o 1.23 m i c r o v o l t s (-116 f r o m 32 Hz
t o 4 KHz, and i s e q u a l t o 3.46 m i c r o v o l t s (-107 i n t h e w i d e s t
bandwidth a t 16 KHz. F o r o c t a v e o r f r a c t i o n a l octave r e a l a n a l y z e r s ,
t h e n o i s e f l o o r i n c r e a s e s b y 3 dB p e r octave toward t h e upper f r e q u e n c i e s .
We would expect t h i s t o happen because n o i s e power doubles f o r each
d o u b l i n g o f t h e f i l t e r bandwidth. The 16 KHz f i l t e r d i s p l a y s t h e h i g h e s t
n o i s e l e v e l because i t has t h e w i d e s t bandwidth. Having bandwidths much
narrower than t h o s e f o u n d
i n o s c i l l o s c o p e s enables t h e
t o measure
s i g n a l s much s m a l l e r t h a n c o u l d be measured w i t h o s c i l l o s c o p e s and most
voltmeters.
F i g u r e 3 1
Due t o t h e h i g h s e n s i t i v i t i e s o f t h e s h i e l d e d coax c a b l e s h o u l d
always be used f o r t e s t l e a d s . The unshielded probe leads s h o u l d be
k e p t as s h o r t as p o s s i b l e . A simple, b u t c i r c u i t probe c o u l d
c o n s i s t o f an a l l m e t a l phono p l u g w i t h c o a x i a l c a b l e and a l l i g a t o r
c l i p s . The i n p u t impedance o f t h i s t y p e of cable, a t audio f r e q u e n c i e s ,
would be t h e ohm impedance o f t h e
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