If Passband Shift; If Notch Filter; Agc (Automatic Gain Control) - Yaesu FT-767GX Operating Manual

To u s e t he A P F, fir s t t u n e in t h e d e s i r e d C W
signal with the APF o f f,
and adjust the A PF contro l for peak vo l u m e on
t he d e s i r e d sig n a l . T u r n t h e A P F o f f b e fo r e
t u ning t o a n e w f r e q u e n cy.
'Tips for C W O peration ' .
4. 6. 7 I F
Passband
The loc a tion o f t h e
t h e c a rri e r f r e q u e n c y o f t he r e c eiv e r i n S S B,
C W, AM and F S K modes can be adjusted by the
S H I FT co n t ro l ( i n n e r k no b on t h e co n t ro l j u s t
b e lo w a n d t o t h e rig h t o f t h e t u n i ng k no b ) .
Think o f t his co n t ro l a s a s lidi ng wi n do w a d ­
j u s t m e n t, whi c h a l lo w s t h e r e c eiving p a s s b a n d
( wi n do w ) t o be s lid b a ck a n d fo r t h, p ro vi di ng
d i f f e r e n t vi e w s of t h e r e c eivi ng f r e q u e n cy.
No r m a l l y, the S H I FT co n t ro l is ke p t in the 1 2
o ' c lo ck posi tio n u n ti l
b e e n t u n e d in. T h e n,
i n t e r f e r e d wi t h by a no t h e r sig n a l j u s t a b o v e
o r b e lo w t h e d e s i r e d o n e,
c a n b e a d j u s t e d to t h e l e f t o r rig h t,
tive l y, to m o v e t he p a s s b a n d w i n do w f a r t h e r
f rom t h e i n t e r fe r e n c e.
a u d io ton e c h a r a c t e r i s t i cs
c h ange : t h i s i s use f u l i n A M r e c e p t io n ,
plementing the TONE con t rol.
Not e : Be fore adjusting the S H I FT contro l,
m a k e s u r e t h e N O T C H fi l t e r i s s w i t ch e d
o f f. A l so , r e t u r n t h e S H I FT co n t ro l to
t h e 12 o ' c lo c k po s i tio n
a no t h e r f r e quency.
4. 6. 8 I F N o t c h F i l t e r
T h e I F no t c h f i l t e r p ro vi d e s a m e a n s t o s u p ­
p r e s s c a r r i e r h e t e ro d y n e i n t e r f e r e n ce i n S S B,
C W, AM and F S K reception.
v a t e d b y t h e s wi t c h o f t h e s a m e n a m e t o t h e
l e f t o f t h e t u n i ng k nob,
inner knob o f the middle contro l at the bo t to m
rig h t . W hi l e a c t i v a t e d, t h e i n di c a to r n ex t to
the NOT C H switch glows green.
The no t c h fi l t e r shou l d
a f t e r t h e d e s i r e d s i g n a l h a s b e e n t u n e d i n,
and after the S H I FT con t rol has been adjusted
fo r mini m u m a d j a c e n t - c h a n n el
Press t h e NOT C H swi t ch and adjust t h e control
g r a d u a l l y b ack and
where the unwanted heterodyne suddenly drops.
and then switch it on
S e e a l so § 4. 1 4
S h i f t
I F p a s s b a n d r e l a ti v e t o
a desi r e d sig n a l
if t h e sig n a l is b ei ng
t he S H I FT co n t ro l
r e s p e c ­
No t i c e a l so t h a t t he
o f t h e rece i ve r
s u p ­
w h e n t u n i ng to
The notch is act i ­
a n d a d j u s t e d b y t h e
b e a c ti v a t e d on l y
in t e r f e r e n c e .
fo r t h to fi n d the po i n t
I f t h e h e t e ro d yne l e ve l i s s t ro nge r t h an t h e
de si r e d sign a l,
d i p w h e n t he no tch i s p ro p e r l y s e t .
no t c h s w i t c h o f f be fo re t un i ng to a ne w fre ­
q u e ncy or a dj u s t ing t he S H I FT co n t ro l .
a l so § 4. 1 3. 3 .
4 . 6. 9 AG C ( Au t o m a t i c G a i n C o n t ro l )
I f you h av e b e e n t u n ing a ro u n d t h e b an d s you
m ay have already not iced that the main m icro ­
processor automatically se lects fast A G C
t he t u n i ng
allows you to de tect weak s ignals while t uning
a c ro s s the b a n d , e ven w hen s t rong sign a l s a r e
p r e s e n t .
W h i l e l i s ten i ng t o a s t a t io n ,
t he A G C decay rate that provides the mos t com ­
fo r t able r e c e p t io n ,
h a s A G C s e l e c to r ( s m a l l kno b ,
right, next to D I M ) .
t his wi l l b e t h e ' S ' ( S lo w ) po si tio n, b u t w h e n
sig n a l s a r e f l u t t e ri ng, o r w h e n looking fo r a
w e ak sig n a l yo u m ay fi n d ' M ' ( M e diu m ) o r ' F '
( F a s t ) be t t e r,
t a ct. Fo r C W,
wi l l b e h e l p f u l
noisy co n di tio n s wi t h w e ak sig n a l s .
b a n d is ve r y q uie t a n d sig n a l s a r e v e r y w e ak,
t he OFF position m ay provide best copy ( don ' t
t ry t his i f i t i s nois y ) .
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t h e S - m e t e r ind ic a t ion
k no b i s ro t a t e d q u ick l y .
yo u c a n se lec t
u s ing t h e fo u r - po s i t ion
seco n d f ro m t he
Usually, for AM and S SB,
a t l e a s t u n ti l yo u m ak e co n ­
the M e di u m o r F a s t po si tio n s
a t hig h e r s p e e d s o r
w i ll
T u r n t h e
S e e
when
Th i s
u n d e r
W h e n t h e