The first SZ test observations with HUMBA were conducted at the IRAM 30m telescope in November 2001. In two hours of on-off observations the SZ decrement was detected toward one cluster. HUMBA has been returned to Bonn for refinements, and is expected to return to the 30m next year.
HUMBAs 18 arcsec resolution is good enough to resolve fine features on intermediate redshift clusters (z~0.2, 18"=>50-100Kpc). It will be the most sensitive instrument to map the SZE toward clusters. Especially the combination of SZE and X-ray observations provides a unique tool to study the structure and physics of the intracluster gas.