  The MAJORANA Collaboration is searching for the neutrinoless double-beta
decay of the nucleus Ge-76. The MAJORANA DEMONSTRATOR is an array of germanium
detectors deployed with the aim of implementing background reduction techniques
suitable for a tonne scale Ge-76-based search (the LEGEND collaboration). In
the DEMONSTRATOR, germanium detectors operate in an ultra-pure vacuum cryostat
at 80 K. One special challenge of an ultra-pure environment is to develop
reliable cables, connectors, and electronics that do not significantly
contribute to the radioactive background of the experiment. This paper
highlights the experimental requirements and how these requirements were met
for the MAJORANA DEMONSTRATOR, including plans to upgrade the wiring for higher
reliability in the summer of 2018. Also described are requirements for LEGEND
R&D efforts underway to meet these additional requirements.
