8-11
10 s
1 s
100 ms
10 ms
1 ms
100 ms
10 ms
1 ms
10
30
1
2
4
8
16
1
2
3
4
5
6
1
2
3
1
2
4
1
minutes
hour
day
week
MONTH
YEAR
Elapsed Time
Text Box: Accumulated Time Error
Accumulated Time Error
Aging rates are per day
Text Box: OFFSET 1 X 10-5
OFFSET 1 X 10-5
Text Box: OFFSET 1 X 10-6
OFFSET 1 X 10-6
Text Box: OFFSET 1 X 10-7
OFFSET 1 X 10-7
Text Box: OFFSET 1 X 10-8
OFFSET 1 X 10-8
Text Box: OFFSET 1 X 10-9
OFFSET 1 X 10-9
Text Box: OFFSET 1 X 10-10
OFFSET 1 X 10-10
Text Box: OFFSET 1 X 10-11
OFFSET 1 X 10-11
Text Box: AGING 1 X 10-5
AGING 1 X 10-5
Text Box: AGING 1 X 10-6
AGING 1 X 10-6
Text Box: AGING 1 X 10-7
AGING 1 X 10-7
Text Box: AGING 1 X 10-8
AGING 1 X 10-8
Text Box: AGING 1 X 10-9
AGING 1 X 10-9
Text Box: AGING 1 X 10-10
AGING 1 X 10-10
Text Box: AGING 1 X 10-11
AGING 1 X 10-11
Text Box: AGING 1 X 10-12
AGING 1 X 10-12
Text Box: AGING 1 X 10-4
AGING 1 X 10-4
Time Error vs. Elapsed Time
To Estimate The Accumulated Time Error*:

 1.  Estimate the initial frequency offset plus the average expected offsets due to temperature
      and other environmental effects.
 2.  Find the time error caused by the sum of the offsets.
 3.  Find the time error caused by the oscillator’s specified aging rate
 4.  Add the results of 2 and 3 to estimate the total time error


*  In the nomograph, the contribution due to aging assumes no resynchronization.  If there is resynchronization, as in the examples on the previous page, then the offset due to aging must first be calculated and added to the other offsets.  For example, in the TCXO example on the previous page, in the four hour resynchronization interval, the offset due to temperature causes a time error of ~14 ms.  The aging after 80 days results in a frequency offset of 8 x 10-7 which results in another ~11 ms error, so, after 80 days of aging, the combined offsets due to aging and temperature result in ~25 ms time error four hours after resynchronization.