Checks and Adjustments
1705A Spectrum Monitor 5-11
k. CHECK -- that the marker tip is on the crt center line ±1 minor
Division (vertically).
8. Check Video Filter
REQUIREMENT-- VideoFilter reduces noise by approximately 50%.
a. Be sure that the VIDEO FILTERis OFF.
b. Position the baseline on screenwith the VERTICAL POSITION control.
c. Switch between VIDEOF ILTERON and OFF.
d. CHECK -- that the baseline noise amplitude drops approximately 50%
when the VIDEO FILTERis ON.
9. Check Sweep Speed
REQUIREMENT-- Typically20 -- 200 ms.
a. Verifythat SPAN/DIV is set to FULL and that SWEEP SPEED is set
fully clockwise.
b. CHECK -- for a solid tracewith almost no flicker.
c. Set SWEEP SPEED fully counterclockwise.
d. CHECK -- for about 3 to 4 sweeps persecond.
e. Return SWEEP SPEED fully clockwise.
Alternate Method
a. Connect the oscilloscope 10X probe to W2.
b. Set the oscilloscope timebaseto 5 ms/Div.
c. Set the oscilloscope verticalto 2 Volts/Div.
d. Set SWEEP SPEED fully clockwise.
e. CHECK -- for a rampduration of 20 ms ±10 ms.
f. Set SWEEP SPEED fully counterclockwise.
g. Set the oscilloscope timebaseto 50 ms/Div.
h. CHECK -- for a ramp durationof 200 ms ±100 ms.
i. Remove probe. Return SWEEP SPEED fully clockwise.