As previously recorded (81), on Thur Oct 13th, A NIM crate failure caused preamp power loss to the HPGe's. While D4 recovered with nominally the same resolution as before. G7 would not recieve power to the preamps without an alarm from the NIM crate.

It was determined that there was a short along the lines of +12V and Ground , -12V and Ground, and between +-12V.

After removing the Red preamp ribbon cable, the remaining channels (K,G,B) were able to be powered on and found to have a nice resolution of near ~2.3 keV for 661 (137Cs).

During the course of testing, the preamp power distribution box (supplied from ORNL) was seen to have a fault in the +12V light and supply. This was seen by placing this supply in a new NIM bin and seeing that it would also not properly supply preamp power to clover D4 (which had recovered fully).

The consistency in this fault is seen as cause to be suspicious of this preamp power supply. It has been replaced by putting two ORTEC TSA's into a seperate NIM bin and using the standard power supply for D4 and G7.

There was no appreciable effect on noise in any other detector.