Agilent Technologies 83640B - Page 265

Accuracy
Versus
Adjustment Interv
al
Figure 3-3
shows
the required
adjustment
interv
al to
maintain
a
giv
en
accuracy
.
If
y
ou
kno
w
the
aging rate,
you
can
determine
a
more
precise
adjustmen
t
in
terv
al.
Figure
3-3.
Accuracy
V
ersus
Adjustment
Interv
al
1.
Find the
line on
Figure 3-3
that corresp
onds
to
the
10
MHz
timebase
oscillator
aging
rate.
(T
o
determine
the
aging
rate,
see
\P
erformance T
ests.")
2. On
the
horizon
tal
axis,
nd
the
maxim
um
allo
w
able error
(accuracy)
that
y
ou
w
an
t.
3. Follo w the maximum allo
wable error v
ertically un
til it in
tersects the kno
wn aging rate.
4. F
rom the p oin
tofin
tersection, mo
ve
horizontally to the left and read the minim
um
calibration in
terv
al measured in da
ys.
An Alternate Method
You can also determine
the minim
um calibration in
terval using the follo
wing form
ula:
maximum allowable error
known aging rate (p er day)
= calibration interval in days
3-8 Adjustments
10 MHz Standard
Agilent 8360