Agilent Technologies HP 8719D Service Manual page 236

1. Monitor the 1st IF signa.I at the output of A65 A sampler: disconnect the
Connect a frequency counter to port 1. Then perform these steps:
b. Press #E gOJuST !EXJ RAC E?!$ LOW B#WP and rotate the front panel
knob to change the DAC number to about 4013. Readjust the DAC number
as required to measure an output frequency of about 0.91 GHz.
Note
The frequency counter may have to be removed from port 1 to
provide enough of a reflection to see on the scope.
2. Now the oscilloscope should display the IF signal as a sine wave of about 10
MHz. The actual frequency can be expressed as this equation:
3. Repeat steps 1b and 2 using the information in the second through fourth
rows of 'Ihble 7-4. Substitute
DAC
Number
Band
(HP 8722DOnly)
If the IF signals are correct, replace the A11.
n
Approximate
DAC Number Source fiequeucy
Displayed
4013
) - (18OMHz) x (hamnic)
Approximate Harmonic
On Canter
3.610 GHz
4.690 GHz
20.17 GHz
5
26
26
112