ADJUSTMENTS

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5-22. 3 dB BANDWIDTH ADJUSTMENTS(SERIAL PREFIX 1909A)(Cont'd)

10.Remove AlOWl from A5J2 2nd CONV OUT Connect step attenuator through adapter to A1OW1.

11.Set HP 8559A RESOLUTION BW to 1 MHz. Adjust the output level of signal generator to place the signal near center graticule line. Tune signal generator frequency to peak signal on oscillo~copedisplay (near 321.4 MHz).

12.Set RESOLUTION BW to 3 kHz. Tune signal generator to peak signal on oscilloscopedisplay.

13, Adjust output level of signal generator to place signal at 7.1 divisions.

14.Note the counter frequency and tune the signal generator 1500 Hz below the center frequency noted. Record the new counter frequency.

MHz

15.Adjust A9R72 XTL to bring signal level to the fifth graticule line (three divisions from the top graticule line).

16.Increase signal generator frequency until signal on oscilloscope display peaks and then decreases to the fifth graticule line. Record counter frequency.

MHz

17.Compare new frequency with frequency recorded in step 14. The difference between the two frequencies should be 2800 to 3200 Hz. If the bandwidth is not within limits, repeat steps 12 through 17, slightly readjusting A9R72 XTL, until the specified limits are achieved.

18.Set RESOLUTION BW to 10 kHz. Tune signal generator to peak signal on oscilloscope display.

19.Adjust REF LEVEL FINE to place signal at 7.1 divisions.

24). Decrease the signal generator frequency until the signal on the oscilloscope display drops to the fifth graticule line. Record counter frequency.

MHz

21.Increase the signal generator frequency until the signal on the oscilloscope display peaks and then decreases to the fifth graticule line. Record counter frequency.

MHz