Mike Fikes | Good attenuator in 8753D external test set @MikeFikes | Uploaded August 2021 | Updated October 2024, 3 hours ago.
This is showing S11 reflecting all of the power back in (open port 1). You can see a nice flat response at all attenuation levels. Compare with youtu.be/bXJYwIjCP2c which shows things prior to replacing the 85046-60006 attenuator in the 85046A external test set.