ARISS/NASA guru Ken Ransom N5VHO reports that the ISS' Kenwood D700 radio is off due to an air purifier running in the Service Module 24/7, and it uses the same power outlet that the Kenwood radio uses.

They only power the purifier off for scheduled ham events and then re-activate right afterwards.

Ken also advises that Flight Engineer Pettit reports the Columbus radio should be back up on packet operating on 437.550.

Clint