
16. YTO Loop Adjustments
32. Set the oscilloscope controls as follows:
Press
(CHAN_):
Channel 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .on
amplitude scale
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200
mV/div
offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..-3OO.OOOmV
coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..dc
Channel 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . on
amplitude scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.00
V/div
offset
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..O.OOOOO V
coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..dc
Press
LTRIG):
EDGE TRIGGER . . . . . . . . . . . . . . . . . . . . . . . . . . trig’d, edge
source
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..Channel4
level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -3.00000 V, rising edge
Press
[TlNlE):
time scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..2.00msec/div
reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..left
Press
(DISPLAY_):
connect dots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..on
Press [SHOW)
33. Press
[INSTR
PRESET) on the synthesized sweeper. Set the
synthesized sweeper controls as follows:
START FREQUENCY . . . . . . . . . . . . . . . . . . . . . .
.87.5
MHz
STOP FREQUENCY . . . . . . . . . . . . . . . . . . .
.287.5
MHz
POWER LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . +3.0
dBm
FREQUENCY MARKER Ml . . . . . . . . . . . . . . . . . . . .
,160
MHz
FREQUENCY MARKER M2 . . . . . . . . . . . . . . . . . . . . . . . ,210 MHz
FREQUENCY MARKER M3 . . . . . . . . . . . . . . . . . . . . . . . .
.187.5
MHz
SWEEP TIME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.20
ms
AMPTD MKR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . on
34. Connect the RF OUTPUT of the synthesized sweeper to AllJ2
M/N IN using a BNC to SMB snap-on test cable.
35. Use a BNC to alligator clip adapter to connect the oscilloscope
Channel 1 input to the RF Section
AllA5TPl
test point, and
connect the Channel 1 ground to the All YTO Loop cover.
Connect the oscilloscope Channel 4 input to the synthesized
sweeper rear-panel NEG BLANKING output. Adjust the
oscilloscope triggering as necessary for a stable display, and then
key in
(CHAN)
Channel 4 off,
[SHOW).
36. The
AllA5TPl
SAMPLER DC waveform displayed on the
oscilloscope should be similar to Figure 3-74. The left, middle, and
right vertical spikes visible on the voltage waveform correspond
to synthesized sweeper marker frequencies of 160 MHz, 187
MHz, and 210 MHz, respectively. Adjust
AllA5C2
to widen the
waveform as far to the left as possible.
Adjustments
3-141
Commentaires sur ces manuels