
8. 21.4 MHz Bandwidth Filter Adjustments
45.
46.
4 7 .
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
Adjust
XTAL to align markers on display. MARKER
A level should indicate 1.00 X. See Figure 3-44 for location of
adjustment.
Dip Adjustments
Refer to the Resolution Bandwidth Switching Uncertainty
Performance Test, and check all bandwidth amplitudes. If
amplitude of 300
bandwidth is low but amplitude of 100
and 1 MHz bandwidths are within tolerance, LC DIP adjustments
must be performed. If all bandwidth amplitudes are within
tolerance, do not perform the following adjustments.
Set LINE switch to STANDBY.
Disconnect cable 97 (white/violet) from
and connect to
J 1.
Remove
Bandwidth Filter and install
on
extenders.
Set LINE switch to ON. Press
PRESET
).
Key in
[
CENTER FREQUENCY
]
20 MHz,
100
SPAN
]
1 MHz,
0
and LOG
(
ENTER
2
Short
to ground.
Adjust.
LC DIP for minimum amplitude of signal peak.
See Figure 3-41 for location of adjustment. Key in
SEARCH
)
MARKER
and adjust LC DIP again to offset the signal peak
approximately -17
(to the left). This is done to compensate
for the effect of placing the board on extenders. If unable to
achieve a “dip” in signal amplitude, increase or decrease value of
Refer to Table 3-3 for range of values.
Remove short, from
and short
to ground.
Adjust
LC DIP for minimum amplitude of signal peak.
See Figure 3-41 for location of adjustment. Key in
[
PEAK SEARCH
)
MARKER In], and adjust
LC DIP again to offset the signal
peak approximately -17
(to
the
left). If unable to achieve a
“dip” in signal amplitude, increase or decrease value of
Refer to
3-3 for range of values.
Set LINE switch to STANDBY.
Reinstall
Bandwidth Filter without extenders.
Short
and
to ground. Remove
Attenuator-Bandwidth Filter and install on extenders. Reconnect
cable 97 to
and reconnect cable 89 to
Set, LINE switch to ON. Press
PRESET
).
Key in
[
CENTER FREQUENCY
)
20 MHz,
100
(
FREQUENCY SPAN
)
1 MHz,
0
and LOG
(
ENTER
Short
to ground.
Adjust
LC DIP for minimum amplitude of signal peak.
See Figure 3-43 for location of adjustment. Key in
SEARCH
)
MARKER
and adjust LC DIP again to offset the signal peak
3-82 Adjustments
Содержание 8568B
Страница 13: ...6 7 IF Section Bottom View 6 10 Contents 7 ...
Страница 19: ......
Страница 37: ......
Страница 42: ......
Страница 48: ......
Страница 53: ......
Страница 54: ...9 RF Gain Uncertainty Test h I 1 I I I Figure 2 16 RF Gain Uncertainty Measurement 2 32 Performance Tests ...
Страница 61: ......
Страница 90: ......
Страница 100: ...Test 9 RF Gain Uncertainty Test Step 6 2nd LO Shift Min Measured Max 1 0 dB 1 0 dB 2 78 Performance Tests ...
Страница 106: ...Test 13 Average Noise Level Test 2 84 Performance Tests ...
Страница 109: ...Test 16 Residual FM Test Test 16 Residual FM Test Step 14 Residual FM IMinIMeasuredIrax Performance Tests 2 87 ...
Страница 162: ......
Страница 224: ......
Страница 268: ......
Страница 270: ......
Страница 272: ......
Страница 278: ......
Страница 307: ...w43 c c5 c4 c3 c2 Figure 6 l RF Section Top View A26 6 4 Major Assembly and Component locations ...
Страница 312: ...AlVl Figure 6 6 IF Section Front View w3 w9 Major Assembly and Component locations 6 9 ...