12. Tune the signal to the extreme left graticule line with
GENERAL OPERATING INFORMATION
the RF CENTER FREQUENCY control. Note the dial reading.
Light Filters
Tune the signal to the extreme right graticule line and note
the dial reading. The difference between dial readings is
The instrument is shipped with a mesh filter installed.
the total dispersion window for this 10 division display. Tune
Two (2) colored filters, plus a clear CRT faceplate protector
the signal to the center of the screen and switch the DIS-
and an ornamental ring are provided with the accessories.
PERSION-COUPLED RESOLUTION selector to the 5 MHz/
The mesh filter improves the contrast when viewing the
div position. Tune the signal across the screen and note
display under high ambient light conditions. The blue and
the total dispersion. It should decrease to approximately
yellow filters can be used to take advantage of the dual
the dispersion noted with the DISPERSION selector in
phosphor characteristics of the P7 CRT.
the 10 MHz/div position. Tune the signal to the center of
the screen.
The mesh filter is removed by pressing down at the bot-
tom of the frame and pulling the top of the holder away
13. Tune the IF CENTER FREQ coarse control through its
from the CRT faceplate. See Fig. 2-5. To install the colored
range. Note that all signals move across the screen in the
filters, press them into the ornamental mounting ring until
same direction and the same amount. This control shifts
they snap behind the retainer lips. To remove the filters
the IF center frequency approximately + and - 25 MHz
from their holder, press them out to the rear.
with the DISPERSION controls in this position. Tune the IF
CENTER FREQ control to center the signal on the screen.
14. Change the DISPERSION selector to .5 MHz/div.
Adjust the FINE (1 turn) IF CENTER FREQ control. Note the
frequency range of this control. This control shifts the IF
center frequency approximately + and - 1 MHz with the
DISPERSION RANGE in this position.
15. Change the TIME/DIV switch between .1 s and .1 ms
positions. Note the change in signal amplitude and the
resolution. Return the TIME/DIV selector to the 10 ms posi-
tion.
16. Push the LOCK CHECK button and tune the RF CENTER
FREQUENCY control very carefully through the signal fre-
quency. Note the phase lock beat signals between the tun-
able local oscillator and the Internal Reference Frequency
oscillator as the display blooms, then snaps into phase lock
operation (Fig. 2-13).
17. With the LOCK CHECK button depressed, adjust the
FINE RF CENTER FREQ control. Note the beat frequency dis-
plays as the control is varied, and note also the vertical shift
of the baseline. This baseline shift is the change in the out-
put DC level of the phase amplifier. Note the zero beat sig-
nal compression at the extreme positions of this control com-
pared to their amplitude near the center. Phase lock should
be set with the output DC level within the center 4 divisions
One of the filters or protector should be used at all times
of the graticule. Adjust for phase lock operation and re-
to protect the faceplate of the CRT from scratches.
lease the LOCK CHECK button.
18. Switch the DISPERSION RANGE switch to kHz/DIV,
Intensity Level, Astigmatism and Focus
then decrease the DISPERSION TO 20 kHz/div, keeping the
signal centered on screen with the IF CENTER FREQ con-
Operate the instrument with the intensity level no higher
trol. Slowly rotate the FINE RF CENTER FREQ control. Note
than the level required to clearly observe the display.
the positive action of the phase lock circuit before lock is
Changing the INTENSITY setting may require refocusing the
lost. Return the signal to its locked mode by adjusting the
display.
FINE RF CENTER FREQ control.
The ASTIGMATISM and FOCUS controls both affect dis-
19. Uncouple the RESOLUTION and turn the control
play definition and are normally adjusted together. If the
clockwise. Note that the signal broadens as the resolu-
ASTIGMATISM control is correctly set, the vertical and hori-
tion bandwidth is increased. The resolution may be varied
zontal segments of the display will focus at the same posi-
from approximately 1 kHz to 100 kHz, Return the RESOLU-
tion of the FOCUS control, The controls are adjusted as
TION control to the coupled position.
follows:
20. Adjust the INTENSIFIER control through its range. This
1. Obtain a display on the analyzer with both horizontal
control suppresses the base of the display, and can be
and vertical information.
utilized when photographing displays at slow sweep rates.
2. Adjust the ASTIGMATISM control for equally focused
See Operation of the INTENSIFIER control. It should be left
vertical and horizontal portions in the display.
in the OFF position for most aperating situations.
2-7
