Tektronix 1705A instruction manual End of Adjustment Procedure

Checks and Adjustments

e.ADJUST - R239 (IF AGC) for maximum signal amplitude.

f.ADJUST - R240 (RF AGC) so the signal is one major Division (±0.5 major Divisions) down from the top graticule line.

g.ADJUST - R232 to its midpoint.

18.Adjust 2 dB/Div Position

a.Disconnect the signal from the L-BAND INPUT.

b.Turn VERTICAL POSITION fully clockwise.

c.Hold the VIDEO push button down until 2 dB/Div appears on the crt readout.

d.ADJUST - R140 to position the noise floor to center screen.

e.Hold the VIDEO push button down again to exit the 2 dB/Div mode.

19.Adjust 590 MHz Notch

a.Select L-BAND INPUT and set the SPAN/DIV to 10 MHz.

b.Connect the signal generator to the L-BAND INPUT.

c.Set the signal generator Frequency to 1200 MHz, and Amplitude to -20 dBm.

d.Use the HORIZONTAL POSITION control to place the 1200 MHz signal at the extreme left graticule mark. A small spur should be visible near the extreme right graticule mark. Note: R240, RF AGC, may be adjusted to ease visibility of the spur. Be sure to reset R240 (step 17 part f.).

e.ADJUST - C69 carefully until spur is minimized. Note: While adjusting C69, note the 1200 MHz amplitude. The spur should be minimized without reducing the 1200 MHz spike by more than 2 dB.

End of Adjustment Procedure

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