Chapter 3 119
Manual Adjustment Procedures
2. IF Amplitude Adjustments
6. If the marker reads less than −60.1 dBm, rotate A4R826 CAL OSC
AMPTD one-third turn clockwise for every 0.1 dB less than
−60 dBm. If the marker reads greater than −59.9 dBm, rotate
A4R826 CAL OSC AMPTD one-third turn counter clockwise for
every 0.1 dB greater than −60 dBm. See Figure 3-8 on page 118 for
the location of A4R826. A change in the displayed amplitude will not
be seen until
ADJ CURR IF STATE is pressed.
NOTE If A4R826 has inadequate range, refer to "Inadequate CAL OSC
AMPTD Range" in Chapter 9.
7. Press
ADJ CURR IF STATE. After allowing the analyzer time to
complete the adjustments, the displayed amplitude and marker
reading should change.
8. Repeat steps 7 and 8 until the marker reads −60 dBm ±0.1 dB.
9. Disconnect the test cable from A5J3 and reconnect W29 to A5J3.
A5 Reference Attenuator Adjustment
10.Set the spectrum analyzer reference level to −60 dBm. If markers
are displayed, press
MKR and MARKERS OFF.
11.Set the 3335A
AMPLITUDE to −60 dBm.
12.Connect a BNC cable between the 50Ω output of the 3335A and the
spectrum analyzer INPUT 50Ω .
13.On the spectrum analyzer, press
CAL and REF LVL ADJ. Use the front
panel knob or step keys to place the peak of the displayed signal
3 dB to 5 dB below the reference level.
14.Press
PEAK SEARCH and MARKER DELTA on the spectrum analyzer.
Set the spectrum analyzer reference level to −10 dBm.
15.Change the 3335A AMPLITUDE to −10 dBm.
16.Press
CAL on the spectrum analyzer.
17.Note the ∆MKR amplitude. Ideally, it should read 50.00 dB ±0.1 dB.
18.If the ∆MKR amplitude is less than 49.9 dB, rotate A5R343 15 dB
ATTEN one-half turn counterclockwise for each 0.1 dB less than
50.00 dB. If the ∆MKR amplitude is greater than 50.1 dB, rotate
A5R343 15 dB ATTEN one-half turn clockwise for each 0.1 dB
greater than 50.00 dB. Do not adjust A5R343 more than five turns
before continuing with the next step.
19.Press
ADJ CURR IF STATE on the spectrum analyzer. Note the ∆MKR
amplitude reading.
20.Repeat steps 11 through 20 until the ∆MKR amplitude reading is
50.00 dB ±0.1 dB.