BENDIX ADF-T12B Maintenance Manual page 37

M A I N T E N A N C E P R A C T I C E S
K E Y I T E M S
D E T A I L S T E P S / W O R K I T E M S
If the indicated frequencies on the tuning dial are
not within 1% tolerance of the signal generator
output frequencies, perform the following
a d j u s t m e n t s :
With the signal generator and the receiver tuning
dial adjusted to 200 kc, adjust local oscillator
tuning coil LIO until the signal generator frequency
can be monitored on the tuning meter at the maximum
i n d i c a t e d l e v e l .
( h )
( i )
Re-adjust the signal generator and receiver tuning
d i a l t o 4 0 0 ' : c .
( i )
Adjust local oscillator trimmer capacitor C39 until
maximum indication is observed on the tuning meter.
(k)
Repeat steps (i), (j), and (k) until it is apparent that
the signal generator output frequencies of 200 and 400
k c a r e r e c e i v e d a t a m a x i m u m i n d i c a t e d l e v e l o n t h e
tuning meter when the receiver tuning dial is adjusted
to these frequencies, respectively.
(1)
Re-tune signal generator to 200 kc and adjust mixer
and R-F coils L7 and L4 (in this order) for maximum
i n d i c a t i o n o n t h e t u n i n g m e t e r.
( m )
Re-tune signal generator to 400 kc and adjust trimmer
capacitors C24 and C21 (in this order) for maximum
i n d i c a t i o n o n t h e t u n i n g m e t e r.
Repeat the foregoing steps at other calibration points
and adjustments as follows;
( n )
( o )
B a n d 2 : 5 0 0 k c : A d j u s t L l l , L 8 , L 5
8 5 0 k c : A d j u s t C 4 1 , C 2 8 , C 1 7
Band 3: 1000 kc: Adjust L12, L19, L6
1 6 0 0 k c : A d j u s t C 4 3 , C 2 8 , C 1 9
(p) Align loop stage. See paragraph 2. E(3) for loop
stage alignment procedures.
(2) Receiver Sensitivity (MOW)
(a) Connect the equipment as illustrated in figure 102,
A l l o w 1 5 m i n u t e s f o r t e s t e q u i p m e n t
w a r m - u p .
Set output meter for 500 ohm load.
(b)
S e t r e c e i v e r f u n c t i o n s e l e c t o r s w i t c h t o R E C
p o s i t i o n .
(c)
N O T E
R-F and I-F alignment procedures must have been performed
before continuing with this procedure.
%
Adjust signal generator to 200 kc, modulated 30%
at 400 cps.
(d)
T u n e r e c e i v e r t o 2 0 0 k c .
(e)
A P R I L 1 9 6 5
(Revised April 1967)
P a g e 11 5