Status of UCSB LT Testing All 10 slots are equipped with UTRI, PAACB and adapter boards. All 10 UTRI connected to multiplexer. All 10 slots have HV connections with bias current monitored by electrometers. 9 cold box plates available with adapter cards mounted on standoffs of correct height. 4 PAACB’s are connected for readout of module temperature sensors and low voltage currents. Software reads out everything that is connected. –

IV curves. Upper T=23C, Lower T=-15C,-18C,-20C Module 1042 Module 1041 Module 1040 Module 1033

Leakage current versus time (temperature).

Module temperature sensor readings (blue, magenta) Heat sink temp (red), carrier plate temp (green)

Module 1037

Large amount of noise occasionally seen in system. Might be faulty backplane connection.

Faulty backplane? Connections through backplane made with stacked wire wrap connectors. Pins are long and fragile and not rounded. Pins have been bent while connecting adapter due to very slight misalignment (~0.02 in) of standoffs. Two HV connections through backplane are open. Made HV connection by using spare pin on PAACB and adapter board. Large noise in the system that can go away when adapter board is reseated on backplane connector. Rebuild backplane using PCB mounted connectors instead of stacked connectors.