Adjustment Procedures
5-22 2715 Spectrum Analyzer Service Manual
d. Select the following settings on the Spectrum Analyzer:
FREQUENCY 100 MHz
SPAN/DIV ZERO SPAN
RES BW 3 kHz
VERT SCALE 1 dB/div
VIDEO FILTER ON
e. Disable DISPLAYS TORAGE by pressing D, and pressSWEEP ↓
twice.
f. Adjust R622 (LOG GAIN) on the Log board for traceshift as the VERT
SCALE is cycled through 10 dB/div, 5 dB/div,and 1 dB/div. If
necessary, set VERT POS (R6) to bring the trace into the viewi ng area.
g. Set the VERTICAL SCALE to 10 dB/div.
h. Adjust VERT POS (R6) on the rear panel to position the trace at the top
graticule line.
2. Adjust Level (R63, R42, R20, R24, R98, R107, R39, and R40 on the
Display Storage board, as follows (See Figure 5-- 2 on Page 5-- 13):
a. Enable the checkerboardpattern (Display Storage adjustment pattern) by
pressing UTIL522.
b. Adjust R63 (VOO) to align the top intensified edgeof the checkerboard
pattern with the top graticuleline.
c. Adjust R42 (VOG) to align the bottom intensified edgeof the checker-
board pattern with bottom graticuleline.
d. Adjust R98 (HOO) to position the center of thecheckerboard pattern at
the center of the screen.
e. Adjust R107 (HOG) for optimum one checkerboard square perdivision
(edges of the intensifiedsquares position to left and right vertical
graticule lines).
f. Repeat steps d and e to optimize horizontaladjustment due to small
interaction between theseadjustments.
g. Press BKSP (once)and adjust R63 (VOO) to center the readouts
between the top and bottom graticulelines.
h. Enable the checkerboardby pressing UTIL522.
i. Adjust R174 (VectorOffset) to align the top intensified line of the
checkerboard with thetop graticule line.
j. Press any menu button five times to exit thecheckerboard pattern.