Data Acquisition Problems

Problem:

Measured amplitude is zero for all cubes.

Possible Cause:

The oscillator may not locked to the 100 MHz reference or to the IF reference. This is a safe bet if the amplitude is exactly 0.00 for all cubes, including the reference cube (ZRG). Use the ZY Status Word (STW) to diagnose this possibility.

Remedial Action:

Ensure that the 100 MHz reference and the IF reference are getting to the oscillator. If so, trouble-shoot oscillator.

Problem:

Measured amplitude is low for some cubes.

Possible Cause:

The servos are not pointing to a corner cube, or the corner cube may be covered (by dew or frost, for instance), or an obstacle may be in the optical path.

Remedial Action:

Check coordinates of the cube under test. Check for any obstructions in the optical path.