[R-390] storage question

[Kenneth]

This does not concern my R390A but other vintage electronics I have, test
gear and some non-operational receivers.  I need to move them into my
un-heated garage.  I am not so worried so much about the Military gear but
there is some non milspec test gear.  The temperatures at this time of the
year can go to 20 below zero F but normally will stay above zero F.  Will
storage at such low temperatures harm these old rig's.

                      Ken de W7ITC