Yaesu FT-101ZD Instruction Manual page 40

VFO UNIT
The VFO UNIT is very critical in its adj ustment.
As well , this is not an area which should ever
require alignment . Questions regarding drift , et c . ,
usually can be traced to other areas o f the trans­
ceiver (instability in the supply voltage, etc. ). For
this reason, all cases regarding VFO rep air should
be referred to an experien ced service technician .
The following components are of interest from a
service standpoint :
TC80 1 i s the band set trimmer.
TC802 is the VFO level set trimmer.
To confirm proper VFO injection , conne ct the
VTVM to the VFO output . Adjust TC802 for a
reading of 1 00 m V .
FREQUENCY
B A N D C RYS T A L
x
1 60 m 6 0 1 1 5 . 9 8 7 5 M H z
8 0 m x 6 0 2 1 7 . 9 8 7 5
x 6 0 3
4 0m 2 1 . 4 8 7 5
2 0 m x 6 0 4 28 . 4 8 7 5
1 5 m x 6 0 5 3 5 . 4 8 7 5
l O m A x 6 0 6
42 . 4 8 7 5
l O m B x 6 0 7 42 . 9 8 7 5
l O m C x 6 0 8 4 3 . 4 8 7 5
l O m D x 6 0 9 43 . 9 8 7 5
JJY/WWY
X 6 1 0 1 9 . 4 8 7 5
Table 6
S E L EC T
SWIT C T H
BOA R D
V C so 1
T C so 1
T RAN S F O R M E R
T60 1
T 6 0 2
T 6 0 3
T 6 0 4
T 6 0 5
T 6 0 6
T607
T 6 0 8
T609
T6 1 0
- 3 8 -
NB-FIX UNIT
Fixed Channel Frequency Alignment
When the optional fixed channel crystals are b eing
used, they m ay be placed exactly on the corre ct
frequency by adjusting TC2 0 1 (for channel 1 ) and
TC202 (for channel Confirmation of the correct
2).
frequency m ay be m ade with an external receiver
or by loosely coupling a probe from the frequen cy
counter to the transmit ter output . A I -turn loop
is usually sufficient to provide indication on the
counter.
PREMIX LOCAL UNIT
Premix Local Alignmen t
1 . Conne ct the RF prob e of the VTVM to pin 1
of MJ3 .
Refe r to Table 6 , and adjust the appro priate
2 .
transformer for a level of 3 00 m V for each
band and crystal , as shown in the table .
PREMIX UNIT
For this alignment , a wideband (not peak) sweep
generator, as well as an oscilloscope , should be
used.
1 .
Press t he EXT sele ct swit ch. Apply 5 .0 - 5 . 5
MHz sweep output t o the VFO output
terminal at the rear apron e xternal VFO jack.
Connect a high-impedan ce probe o f an oscillo­
scope to J 3 0 1 .
Adjust the transform ers shown i n Table 7
2 .
for a flat response across the entire p assban d .
If you have never adjusted a bandpass filter
previously , this may take some practice .
Perform the adjustments on each b and , ac­
cording to the chart .
T RA N S -
F O R M E R
B A N D
1 6 0 m T 3 0 1 , T J 0 2
8 0 m T 3 o 3 , T 3 o 4
4 0 m T 3 o 5 , T 3 o 6
2 0 m T 3 0 1 , T J o s
1 5 m T 3 o 9 , T 3 1 0
l O m A T 3 1 1 , T J 3 2
JJY / W W V
T J 1 3 , T3 1 4
Table 7
P A S S B A N D
( )
1 0 . 4 - 1 1 . 0 M H z
1 2 . 4 - 1 3 . 0
1 5 . 9 - 1 6 . 5
2 2 . 9 - 2 3 . 5
2 9 . 9 - 3 0 . 5
36 . 9 - 39 . 0
1 3 . 9 - 1 4 . 5