Icom IC-726 Service Manual page 31

PLL
AND
DDS
UNITS
-L53—
—so
MHir
1st
LO
-L59
—
outpui
Itvel
_l_g0
a^Jjustment
"L
6
T—
P5
HF/50
MHz
1
St
LO
output
^eve] cti&cK poEnt
R
77
1st
LQ
loch voltage
check
point
1
fr(
LO
lock voJtage
adjustment
ODS
UMIT
R70
RIT adjustment
R133 ODS
loop
check
point
L 30
DDS
loop adjustment
P 4
Reference frequency
Check
point
HF
2nd LO
output
leveJ
check
point
Cl DDS
cipck
adjustment
IC4, pin 11
or
ICS, pin 11
DOS
clock Check
point
Reference frequency
adjustment
Cl 34
Reference frequency
pre&eltfng
PLL
ADJUSTMENT
{CONTINUED)
ADJUSTMENT ADJUSTMENT
CONDITIONS
* Displayed'
frequency;
14,
lOOOO
MHz
*
Mode
:
USE
+ Terminate Pc
v/ilh
a 50
O
resi&tPr,
*
Receiving
HF
2nd
LO
OUTPUT
LEVEL
UNIT
MEASUREMENT
LOCATION
Connect
the
RF
voftmeier
to P6.
Alter confirmation,
remove
tfie
resistor
from
PS
and
re^plug P5.
* Display ed (requency;
1
4^0000
MHz
•
Mode :USB
* Terminate P4
with
a
50 -0 resietcr-
•
Receiving
Connect
the
RF
voitmetor lo P4.
2
Alter c^>^Firmation^ remove
the resistor
from P4
and
re-plug P4.
* Displayed frequency; 14.10000
MHz
*
Mode
:
USD
* Attach the
SSG
to the [HF
ANT]
connector and
set
as;
Level
;
50
pV'{-T3 dBm)
Modulation:
OFF
* [RIT]
swilch
:
ON
and
OFF
* Receiving
Top
:
Speaker
Cover
VALUE
ADJUSTMENT
POINT
UNIT
ADJUST
PLL
Verify
Maximum
level
[Mere lhan -1-3
dBm)
PLL
Verify
Preset ic center.
Frcnl
panel
[RIT]
centre!
Sanne tece
pitch
cm
t?ctf>
conditions.
More
than
0 dGnn
*
Tills oulpuE lavef qf the standard signal
generator (SSG)
i-s
indicated as
SSG's epen
eirtuii.
6-3