Tektronix 1705A, Instruction Manual

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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.