Tektronix 1L20, Инструкция по эксплуатации

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Calibration— Type 1L20
Fig. 6 -1 4 . Setup for checking RF CENTER FREQ Calibration and Phase Lock (Step 8 ) .
8. Check RF CENTER FREQ Calibration and
Phase Lock Display
NOTE
If th e fo llo w in g procedure indicates th a t the Local
O s c illa to r frequency c a lib ra tio n is o u t o f tolerance,
th e instrum ent should be returned to T e ktro n ix fo r
re c a lib ra tio n — see pag e 4 -1 .
a. Connect the equipment as shown in Fig. 6-14.
b. Preset the front-panel controls o f the analyzer as
directed in Step 7a.
c. Check the Band 1 frequency calibration every 10 MHz
by applying the appropriate —70 dBm signals. Maximum
dial error for this step (and c, d, and e following) is
± 2 MHz
+ 1 % o f the dial reading.
A t the same time, while changing the RF CENTER FREQ
control setting, drepress the LOCK CHECK pushbutton and
check for phase-lock zero beats about every 1 MHz. Check
for a phase-locked display a t 10 MHz, 100 MHz, and 270
MHz.
d. Move the generator output to the BANDS 2-5 RF
INPUT connector and check the dial accuracy every 100 MHz
from 275 MHz to 475 MHz. Check the phase-lock zero beats
as before, and check for a phase-locked display a t 275 MHz
and 500 MHz.
e. Check the dial accuracy a t 500 MHz, 700 MHz, and
900 MHz, using the second harmonic o f the signal generator.
Check for zero beats as before and check for a phase-locked
display at 900 MHz.
f. Since Bands 3, 4, and 5 use harmonics of the frequen­
cies checked in d and e above, it follows that if the dial cali­
bration o f Band 2 is within specifications, Bands 3, 4 and 5
w ill also be w ithin specifications.