Adjustment Procedures
2715 Spectrum Analyzer Service Manual 5-23
k. Disconnect P190 and reconnectthe 10 MHz signal to P190 as was done
in step 1, c on Page 5-- 21.
l. Press LIN and add proper externalattenuation to the input signal to place
the nonstored trace at the bottom graticule line.
m. Adjust R20 (VIO) to match the position of the storeddisplay to the
nonstored display at the bottom graticuleline. (Pressing D repeatedly
alternates the display betweena nonstored and stored trace.)
n. Press LIN and remove external attenuationto place the nonstored trace at
the top graticule line.
o. Adjust R24 (VIG) to match the position of the storeddisplay to the
nonstored display at the bottom graticule line.
p. Repeat steps l through o to compens ate for interaction between the
adjustment of R20 and R24.
q. Disconnect the 10 MHz signal connectedto P190 (step 1, c on Page
5--21) and reconnect P190.
r. Set the FREQ/SPAN to 100 MHz, FREQUENCY to 500 MHZ, REF
LEVEL --30 dBm, RBW 300 kHz, and enable the calibrator by pressing
INPUT 9. Turn display storageoff by pressing DISPLAY STORAGE D
and press VID FLTR to turn the video filteroff.
s. Turn the readoutoff and position the center mark at center screen.
t. Adjust R39 (HIO) to align the stored display to thenonstored display at
center screen. (Pressing DISPLAY STORAGE D repeat edly alternates
the display between stored andnonstored trace).
u. Adjust R40 (HIG) to align the stored display to thenonstored display.
one division from the left and rightedges, at center screen vertically.
v. Enable DISPLAYS TORAGE D.
w. Enable REF LEVEL FINE and using the REF LEVEL ↑↓ keys, move
one of the signals to the first majordivision down from the top of the
screen.
x. Adjust R181 (VectorLength) while repeatedly pressing DISPLAY D
until the peak of the digitized signal matches the peak of the analog
signal.
y. Set FREQ/SPAN to ZERO SPAN,F REQUENCY to 100 MHz, RES
BW to 3 kHz, VIDEO FILTERon, and CALIBRATOR Off.
z. Insert 30 dB of attenuation in the input signalpath using the external
attenuators.