Tektronix 1705A - page 103

Checks and Adjustments
5-8 1705A Spectrum Monitor
a. Adjust FOCUS, INTENSITY,SCALE, and SWEEP SPEED for a
useable display.
b. Place the 2nd marker on the left edge of the graticule. See Figure 5-2.
ALIGN2nd
MARKER HERE
CHECK THAT 3rd
MARKERIS +/-- 1 MINOR
DIVISION FROM HERE
Left edge of
graticule
3rd major
graticule division
4th major
graticule division
Figure5 -2: Check time mark graticule alignment
c. CHECK --for 10 frequency markers from beginning to endof sweep.
d. CHECK-- that each marker is within 1 mino rD ivision of a major
graticuleline when the 2nd marker is on the left edge of the graticule
(see Figure 5-2).
5. Check70 MHz SPAN/DIV and Readout
REQUIREMENT—One marker per 5 Divisions ±1 Division. Readout
accuracy: L--Band±20 MHz. 70 MHz ±2MHz.
a. Select 1 MHz SPAN/DIV.
b. Set the CENTER FREQUENCY to read 70 MHz.
c. Center the readoutcaret horizontally on screen.
d. CHECK-- for 1 marker every 5 major Divisions, ±1 major Division.
Readjust CENTER FREQUENCY,if necessary.
e. Repeat with CenterF requencyat 50 MHz and 90 MHz.
f. Connect the leveled sine wavegenerator to the 70 MHz input without
the comb generator. See Figure 5-3.