Tektronix 1705A User Manual
Page 110
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Checks and Adjustments
1705A Spectrum Monitor
5- 15
s.
CHECK
-- that the readout still reads 1000,
±10.
t.
Set SPAN/DIV to 1 MHz.
u. CHECK
-- that the marker is on screen. Position the marker under the
caret with the CENTER FREQUENCY control.
v.
CHECK
-- that the readout still reads 1000,
±10.
w.
Set SPAN/DIV to 100 kHz.
x.
CHECK
-- that the marker is on screen.
y.
Repeat steps m. through x., substituting 1700 MHz.
12. Check L--Band Gain and Flatness
REQUIREMENT
-- Flatness:
±5 dB (± from center (1400 MHz)).
Relative Amplitude Accuracy
±3 dB/100 MHz. (Typically ±1 dB/100
MHz.)
a.
Set SPAN/DIV to FULL.
b.
Set the 1705A SWEEP SPEED fully counterclockwise.
c.
Set the UHF signal generator Frequency to 1400 MHz and Amplitude to
--30 dBm. Position the tip of the marker to the --10 graticule reference
line (vertical scale).
d.
Change the UHF signal generator Frequency to 950 MHz.
e.
CHECK
-- that the marker is on the same crt center line (vertically),
±0.5 Division.
f.
Change the UHF signal generator Frequency to 1700 MHz.
g.
CHECK
-- that the marker is on the same crt line (vertically),
±0.5
Division.
h.
Set the UHF signal generator Frequency to 1400 MHz.
i.
Position tip of marker to crt center.
j.
CHECK
-- that the marker tip is on the --10 graticule reference line,
±0.5 Division. Note: Make sure that the baseline is on the --70
graticule reference line.
13. Check Positioning Range
REQUIREMENT
-- Vertical: + and --3 Divisions, Horizontal: + and --2
Divisions.