August 2002 - MITLL3 and MITLL2a suffered failures in 2002A.
MITLL3 has been repaied and returned to service. MITLL2A cannot be repaired
and is no longer offered.
March 2000 - MITLL2 suffered a catastrophic failure in January
2000. This was due to a design flaw in our Oxford Instruments dewars, which
saw weakened dewar support struts chew Al shavings from the dewar wall.
These worked their way throughout the dewar, and appear to have enventually
damaged the on-chip amplifier then in use.
In March 2000, the chip was returned to Epping, where John Barton swapped
its operation to the other amplifier. From this date forward the device
was known as MITLL2A. As of April 6, it has successfully been used
on UCLES. See the MITLL2A page for further information. |