ASA 312 Network Information Computer Calibration Manual
DS1 and Frequency Adjustment Calibration
Draft 1 — DLI Proprietary Information 4/15/02
2-3
– If the frequency reading is above 772 KHz, use the keypad to enter a
value that is less than the value that appears, and then press
Enter
to lower
the frequency.
For example, if the
Frequency Adj
command is
128
, enter a value between
0
to
127
.
– If the frequency reading is below 772 KHz, use the keypad to enter a
value that is greater than the value that appears, and then press
Enter
to
raise the frequency.
For example, if the
Frequency Adj
command is
128
, enter a value between
129
and
255
.
You may need to wait several seconds before the ASA 312 accepts the change,
and the new frequency value appears on the frequency counter display.
4. Observe the signal frequency on the frequency counter. If necessary, repeat
Step 3 until the signal frequency is within the range of 772 KHz ± 1 ppm.
5. After adjusting the frequency, you can save the new frequency value using the
procedures described in Chapter 6, Saving Calibration Values and Passwords,
or you can proceed to the next calibration section.
DS1 Positive and Negative Peak Settings
The DS1 Range setting represents the gain or scale applied to the DS1 signal.
There are eight calibration values related to the DS1 measurement. During this
procedure, you will measure and enter the positive and negative peak values for
the first range, and then repeat this procedure for the remaining six ranges.
Review these procedures before attempting to calibrate DS1 parameters.
Required Equipment
The following equipment is required to perform this procedure:
■
ASA 312
■
Function generator
■
Digital oscilloscope
■
BNC T-connector
■
A 2-ft, 75-ohm coaxial cable with male BNC connectors
■
A BNC-to-Bantam, 75 ohm test cord
This is a 3-ft 75 ohm coaxial BNC-to-Bantam cable (AC coupled) that is
available from Digital Lightwave, Inc. (Part Number 001901). Some of
these cables have a blue boot near the BNC connector.
