Sequerra 1 Owner's Manual - page 12
6. S l o w l y t u r n I n t e n s i t y A d j u s t m e n t Clockwise u n t i l a very d i m (barely visible) trace
appears o n the scope's screen. It is i m p o r t a n t t o keep this trace e x t r e m e l y d i m . A u t o
matic brightening c i r c u i t r y w i l l adjust the i n t e n s i t y as required d u r i n g performance. A
bright spot w i l l cause burn-in and shorten the oscilloscope tube's life. Such use w i l l void
the w a r r a n t y . N o w adjust the Focus c o n t r o l u n t i l the scope's trace becomes the smallest
possible d o t . A g a i n adjust t h e I n t e n s i t y c o n t r o l f o r the d i m m e s t possible d o t . The
Vertical and H o r i z o n t a l c o n t r o l s are used t o b r i n g the d o t i n t o the exact certer o f the
scope. T o p r o p e r l y center t h e d o t , observe the tube e x a c t l y dead-on-center f r o m the
f r o n t t o a v o i d any parallex. Use the center vertical line w i t h its center cross mark t o
locate t h e exact center.
Muting Level — T h i s a d j u s t m e n t is used t o t u n e o u t all signals having noise level w h i c h is
unacceptable t o y o u .
1. Depress the M u t i n g : O f f p u s h b u t t o n .
2. T u n e in a station w h i c h y o u consider t o be o n the threshold o f having an unacceptable
noise level.
3. Depress the M u t i n g : I n t e r - S t a t i o n p u s h b u t t o n .
4 . A d j u s t the M u t i n g Level c o n t r o l t o the p o i n t where that station just mutes o u t .
N o w any station w i t h a noise level equal t o , or more than the station just used w i l l be m u t e d
o u t as y o u t u n e t h r o u g h the F M b a n d . T h i s m u t i n g level applies to b o t h the M u t i n g : I n t e r - S t a t i o n ,
and M u t i n g : Inter-Stereo p u s h b u t t o n s . The p o t e n t i o m e t e r used for the M u t i n g Level c o n t r o l has a
range o f 3 m i c r o v o l t s t o 3 0 microvolts.
Panoramic Sweep — T h e electronics for the panoramic display f u n c t i o n is o p t i o n a l and is n o t
included in all sets. A g a i n , remember that all tuners are adjusted before leaving the factory. B u t , in
the event the panoramic trace needs a d j u s t m e n t , f o l l o w these procedures. T h i s task can be made
simpler w i t h a proper understanding o f w h a t ' s o n the screen. The i m p o r t a n t thing to understand is:
1. T h e vertical lines o n t h e graticule are designed t o be 4 0 0 Hz apart.
2. T h e FCC frequency assignments t o alternate ( p r i m a r y ) stations are 4 0 0 Hz apart. T h i s
spaces the adjacent stations m i d w a y ( 2 0 0 Hz) between the alternates.
In relative strong signal areas, it m a y be advantageous t o remove the antenna leads and replace
them w i t h a small piece o f w i r e . A l t h o u g h the pips w i l l n o t be as strong, they m a y be more easily
adjustable.
T o A d j u s t Centering:
1. Depress the Display:Panoramic p u s h b u t t o n and t u n e f o r a p r i m a r y station b y centering a
large p i p .
2. N o w depress the D i s p l a y : T u n i n g p u s h b u t t o n for more accurate center tuning and checking
the station frequency o n the digital r e a d o u t .
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