6. Calibrate the YIG Frequency Linearizer DACs as
follows:
a. At the $prompt, type: calterm 127 and
press <ENTER>.
b. Follow the instructions on the screen. Enter
the value of the frequency counter reading as
XXXX MHz.
c Record step completion on the Test Record.
7. Calibrate the 100 MHz Reference Oscillator as
follows:
a. If Option 16 (High Stability Time Base) is in-
stalled, disconnect the cable at A3J6.
b. Connect the frequency counter to the 682XXB/
683XXB RF output connector.
c. At the $prompt, type: calterm 130 and
press <ENTER>.
d. Follow the instructions on the screen.
e. Reconnect the cable to A3J6, if removed.
f. If Option 16 is installed, use a Phillips screw-
driver and remove the screw on top of the
10 MHz High Stability Crystal Oscillator as-
sembly to gain access to the timebase adjust-
ment screw.
g. Using the Phillips screwdriver, adjust the ti-
mebase to obtain a frequency counter reading
of exactly 10 GHz.
h. Record step completion on the TestRecord.
8. Calibrate the Ramp Center DAC as follows:
a. At the $prompt, type: calterm 129 and
press <ENTER>. (The $prompt will appear on
the screen when the calibration is complete.)
b. Record step completion on the Test Record.
9. Calibrate the Sweep WidthDAC as follows:
a. At the $prompt, type: calterm 133 and
press <ENTER>. (This calibration can take ap-
proximately 2 minutes to complete.)
The $prompt will appear on the screen when
the calibration is complete.
b. Record step completion on the Test Record.
682XXB/683XXB MM 4-15
PRELIMINARY
CALIBRATION CALIBRATION
NOTE
Because the 100 MHz Calibration
DAC is an 8-bit DAC, adjustment
resolution is typically 400 Hz/step.