Yaesu FT-101E - 15. TRAP COIL ALIGNMENT

15. TRAP COIL ALIGNMENT
(4) T113 in the high frequency IF unit is used to el-
(1)
T107
is
used
to
eliminate
the
direct-feed-through
in-
iminated
spurious
radiation
on
the
20
meter
band.
For
terference at the IF frequency, and tuned to 5,720
KHz. Set the transceiver at 7,300 KHz LSB in receive
mode and peak the PRESELECTOR for maximum
noise output. Set the RF signal generator to 5,720
KHz and increase the signal generator output until an
audio beat note is heard. Adjust T107 for minimum
audio output.
alignment, tune transceiver to maximum output at
14,350 KHz in the tune postion. Measure the spurious
radiation, by using the S-meter of another receiver
tuned to 14,520 KHz where a spurious radiation
can be heard. Adjust T113 for minimum S-meter
reading wihout decreasing the power output of the
transceiver.
(5)
T115
is
located
on
the
printed
circuit
board
near
the
VFO
unit
and
is
used
to
suppress
carrier
oscillator
(2)L29 on the printed circuit board located near the
antenna change-over relay RL2 is also used to
feed-through
.
Tune
the
transceiver
to
any
frequency
and
load
it
to
full
output.
Reduce
the
microphone
gain
to
zero
and
place
the
mode
switch
in
the
USB
position.
Adjust
T115
for
minimum
S-meter
eliminate the direct- feed-through interference. Set the
transceiver at 7,080 KHz in the receive mode. Tune
the
RF
signal
generator
to
5,940
KHz.
Adjust
L29
for minimum S-meter reading.
reading on the receiver.
3) L22 eliminates the interference by 9th harmonic of
the carrier oscillator. Tune the transceiver to 28,600
KHz USB in the receive mode, and increase RF and
AF gain control until an audio beat note is heard.
Adjust L22 for minimum audio output.
(6)
L28
is
used
to
eliminate
spurious
radiation
on
the
15
meter
band.
Tune
the
transceiver
to
maximum
output
at
21,200
KHz
in
the
tune
position.
Locate
the
spuri-
ous
radiation
at
21,220
KHz
by
another
receiver.
Adjust
L28
for
minimum
S-meter
reading
on
the
CAUTION
ae
receiver.
Continuous full output for more than 10
seconds may result in destruction of final
tube.
(7)
TC30
connected
in
series
with
L32
on
the
printed
circuit
board
located
on
the
main
chassis
near
the
relay
RL1
is
used
to
eliminate
spurious
radiation
on
10
meter
band.
For
alignment,
tune
transceiver
—
to
maximum
output
at
28,500
KHz
in
the
tune
position.
Measure
the
spurious
radiation
by
using
the
S-meter
of
another
receiver
tuned
to
28,160
KHz
where
the
Spurious
signal
can
be
heard.
Adjust
TC30
—
for
minimum
S-meter
reading
without
decreasing
the
power
output
of
the
transceiver.