Table
Sweep Width Sweep Time RES BW RANGE MA1 MAO
|
| Adjusted |
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|
|
|
|
|
20 kHz | 5 ms | 10 kHz | $5 | V | 0V | 0V | ||
10 kHz | 10 ms | 3 kHz | +5 | V | 0 | V | +5v | |
4 kHz | 30 ms | 1 kHz | +5 | V | +5 | V | 0 V | |
2 kHz | 60 ms | 300 Hz | +5 | V | +5 | V +5 V | ||
The spectrum analyzer performs an automatic adjustment of the IF Section whenever needed.
The Cal Oscillator on the A4 assembly provides a stimulus signal which is routed through the IF during the retrace period.
The A3 Interface assembly measures the response using its
When IF ADJ is on, the analyzer readjusts part of the IF circuitry during each retrace period to readjust the IF completely every 5 minutes.
Automatic IF adjustment is performed upon the following conditions:
w Power on: (unless STOP ALIGN is pressed). The IF parameter variables are initialized to
values loaded in program ROM and all possible IF adjustments are made. If STOP ALIGN is pressed, the adjustment is halted.
nIf REALIGN LO & made with the most
IF is selected: All possible IF adjustments (and LO adjustments) are recent IF parameter variables used as the starting point.
w If FULL IF ADJ is selected: All possible IF adjustments are made with the most recent IF
parameter variables used as the starting point. (FULL IF ADJ is located in the ICAL) menu.)
w If ADJ CURR IF STATE is selected: All amplitude data and some resolution bandwidths are adjusted. The bandwidths adjusted are a function of the currently selected resolution bandwidth setting.
nBetween sweeps: IF ADJ must be set to on. When IF ADJ is off, an A is displayed along the left side of the graticule.
If a FULL IF ADJ sequence cannot proceed beyond the amplitude portion, check the output of the A4 Cal Oscillator as follows:
1.Disconnect cable W52 (coax 9) from A5J4. Connect cable W52 to the input of a second spectrum analyzer.
2.Set the second spectrum analyzer center frequency to 10.7 MHz and the reference level to - 3 0 dBm.
3.On the spectrum analyzer under test, press FULL IF ADJ and observe the display of the second spectrum analyzer
4.If a
IF Section