Checks and Adjustments

k.CHECK - that the marker tip is on the crt center line ±1 minor Division (vertically).

8.Check Video Filter

REQUIREMENT - Video Filter reduces noise by approximately 50%.

a.Be sure that the VIDEO FILTER is OFF.

b.Position the baseline on screen with the VERTICAL POSITION control.

c.Switch between VIDEO FILTER ON and OFF.

d.CHECK - that the baseline noise amplitude drops approximately 50% when the VIDEO FILTER is ON.

9.Check Sweep Speed REQUIREMENT - Typically 20 - 200 ms.

a.Verify that SPAN/DIV is set to FULL and that SWEEP SPEED is set fully clockwise.

b.CHECK - for a solid trace with almost no flicker.

c.Set SWEEP SPEED fully counterclockwise.

d.CHECK - for about 3 to 4 sweeps per second.

e.Return SWEEP SPEED fully clockwise.

Alternate Method

a.Connect the oscilloscope 10X probe to W2.

b.Set the oscilloscope timebase to 5 ms/Div.

c.Set the oscilloscope vertical to 2 Volts/Div.

d.Set SWEEP SPEED fully clockwise.

e.CHECK - for a ramp duration of 20 ms ±10 ms.

f.Set SWEEP SPEED fully counterclockwise.

g.Set the oscilloscope timebase to 50 ms/Div.

h.CHECK - for a ramp duration of 200 ms ±100 ms.

i.Remove probe. Return SWEEP SPEED fully clockwise.

1705A Spectrum Monitor

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Tektronix 1705A instruction manual