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I MODEL 4OO TRANSCEIVER
D,
Alignment and Troubleshooting (Cont)
3.
Set PA grid tuning Iully clockwise,
phone -cw switch in Phone Position,
sideband selector in USB Position.
P r o c e d u r e :
Adjust bandswitch to band shown and
adjust coils for Peak VTVM !eading as
follows:
Function
Switch
Band
vFo
F r e q ,
( t . )
Adjust
Tune*
8 0
4 , O 2 5 L Z O ' , L 3 0 5 ,
c I 5 0 7 , z L 4 0 l
T u n e
4 0
7 , 3 5 0
L204, L304
Tune
z o
r 4 , 5 0 0 L Z 0 3 , L 3 0 3
Tune
2 1 , 5 0 0 L Z | Z , L 3 0 Z
Tune
I O
2 9 , ? 0 0 L 2 0 r , ! 3 0 1
* Note:
I{ VTVM
and field strength meter
exceed ful1 scale readinS,
gwitch to
t r a n s m i t p o s l t r o n a n d i n s e r t c a r r i e r
w i t h c a r r i e !
b a l a n c e c o n t r o l t o k e e p
reading on scale.
Fietd Btlength meter
and VTVM
must both Peak at same time
since it is possible to t|.1ne the coils to
t h e V F O l r e q u e n c y o n l 0 m e t e r s .
C a r e
rnust be taken that the coils be hrned
pro pe rly.
Following
the above Procedures,
replace
o r a n g e w i r e t o P i n I o f t e r m i n a l
s l r i P
adjac ent to V5.
ALIGNMENT
OF 5T?5 KC
TILTER
TRAP
W i t h R F a n d A F g a i n a t m i d s c a l e ,
f e e d
5I?5kc
signaf to antenna connector
and
adj\rst L60Z until heterodyne
di€aPPea!8
o ! S - m e t e r r e a d s z e r o '
ADJUSTMENT OT CARR]ER
FREOUENCY
A.
With dummy load and outPut meter
attached, tun€ transceiver for lnaxi-
rnurn otrtput.
B .
N u l l o u t c a r r i e r w i t h P T T P r e s s e d
and set reBting Plate current to 50
ma wlth bias Pot.
C,
Connect AF generator to MIC JACK '
adjust MIC, GAIN full CCW-
P r o c e d | 1 ! e :
W i t h A F g e n e r a t o r a t 1 5 0 0 c P 3 ,
i n c r e a e e M I C . C A I N t o P ! o d u c e a
100 ma, reading on the meter.
Adjust 2801 for rnaxirnuln meter
r e a d i n g .
L
z .
3. Adjust both toP and bottom corea of
Zl40l
for maxirnlrm rnetei reading.
4.
Adjust MIC. GAIN for t'teter read-
ing of 300 rna.
5 . S e t A F g e n e r a t o r t o 3 0 0 c P s . A d j u s t
C 1 5 0 7 I o r m e t e r r e a d i n g o f 7 5 m a .
6. Repeat stePs I through 5 for USB
o p e r a t i o n , a d j u 6 t i n g C 1 5 0 6 .
PA NEUTRALIZATION
W i t h P . A . c o a t s e l o a d i n p o 6 i t i o n I , s e t
{req. to 14. 150, PA Plate control at 9
o r c l o c k , i n s e r t c a r r i e r a n d p e a k P . A .
Crid control, adj\rsting Car. Bal. con-
trol for 200 MA,
Turn PA control
slowly thlough iesonance.
Cathode
current should diP srnoothly and rise to
2OO MA on the 1oll caPacitY side of
re6onance.
If, instead, there i6 a peak
above ZOO MA either side of the dlP'
stop rotation of the PA plate control at
t 9
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