Checks and Adjustments

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.

1705A Spectrum Monitor

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Tektronix 1705A instruction manual