IVIE IE-10A, Руководство владельца и оператора

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CALIBRATION LINE
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I 1 1 1 1 1 1 1 1 1
I I I 1 1 1 1 1 1
3 - - - - d m - - - .
4
* N o t e s e t t i n g s o f S E N S I T I V I T Y
s w i t c h e s
.
d e t e c t o r s s h o u l d
be
i n
p i n k
noise
a v e r a g i n g m o d e .
F i g u r e 6
Increase t h e DISPLAY switch r e s o l u t i o n t o 2 dB p e r step, and then
t o 1 dB per step. The p i n k noise should remain a t t h e dB l i n e , b u t i f
i t does not, r e a d j u s t t h e reference on t h e Now you a r e c a l i b r a t e d ,
and t h e o u t p u t v o l t a g e on t h e i s equal t o 940 mv
Now
t r y
another experiment w i t h the -S e t t h e d i a l a t t e n u a t o r
on t h e t o 12 dB.
As you switch t h e d i s p l a y r e s o l u t i o n on t h e
between 1, 2, and 3 dB, note t h a t t h e s i g n a l i s 12 dB down from t h e
.
c a l i b r a t i o n l i n e dB) on a l l three d i s p l a y scales.
The r e s o l u t i o n
s e t t i n g s on t h e a n a l y z e r always expand around t h e dB r e f e r e n c e l i n e .
As analyzer r e s o l u t i o n reaches 1 dB per step i t can be observed t h a t
p i n k noise i n t h e l o w frequency f i l t e r s appears l e s s s t a b l e i n amplitude
when viewed on t h e This i s a occurence w i t h any p i n k
noise source and a n a l y z e r , and i s due t o t h e random n a t u r e o f p i n k n o i s e
and t h e f a c t t h a t t h e l o w frequency f i l t e r s have narrower bandwidths.
If p i n k n o i s e i s averaged over a long p e r i o d o f time i t w i appear v e r y
f l a t w i t h l i t t l e v a r i a t i o n i n amplitude. Using a l o n g d e t e c t o r time
would be f o r c e d t o w a i t f o r an excessively l o n g t i m e p e r i o d
f o r t h e a n a l y z e r t o respond t o a change i n frequency response and we
would have something' l e s s than a " r e a l analyzer.
The
detectors a r e o p t i m i z e d f o r best s t a b i l i t y versus f a s t response time of
t h e d i s p l a y e d s i g n a l . High r e s o l u t i o n measurements need n o t be l e s s
accurate i f we s i m p l y observe the l e v e l a t which t h e spend most
t h e time.
P I N K NOISE TESTING
Using p i n k n o i s e as a s i g n a l source w i t h t h e
w i l l
e n a b l e a measurement
of frequency response and gain ( o r l o s s ) simultaneously.
The s i m p l e s t
way t o describe t h e procedure i s through t h e use o f a few examples.
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