Insulator/shielding in DEC power supply

[Ian King]

I'm reconditioning some H7100A power supply units in a VAX-11/785, and I've come across something I haven't seen before.  I'm hoping one of you has.  :)

This particular PSU was labeled 'Memory Power Supply' and has additional regulator boards for a 15v rail.  Slipped between those boards were two sheets of what looked like heavy-duty paper.  However, one had delaminated, demonstrating that it is a sheet of thin copper sandwiched between two paper-like layers.  That suggests to me that this was intended more for EMI shielding than electrical isolation.  I did not see these sheets in another PSU that also had a supplemental regulator.

Does this sound familiar to anyone?  TIA - Ian

UNIX is user friendly.  It's just selective about who its friends are.
Ian S. King, Vintage Systems Engineer
Vulcan, Inc.
http://www.pdpplanet.org