[R-390] IF Transformer Covers

[Tim Shoppa]

Barry asks:
> The IF deck alignment procedures call for transformer covers with
holes in 
> the top to expose the slug drives.  I really don't want to put holes
in my 
> permanent covers.  Anyone have a suggestion where I might find some
spare 
> covers I can use for this?  I figure the sizes used to be fairly
common and 
> available (old TV radios and TVs, etc.), but not sure where I could
find 
> those now.

390 or 390A?

At least in my 390A either my covers already have the holes or
I can swap around with other cans which have the holes.

A non-historically accurate but easy "modern" way to make very
good shields is to use modern thin unetched PCB. Cut it with scissors,
join it with a soldering gun, round it with a file. I'm sure the purists
who will never use a frequency counter or a scope to align their 390
because they aren't mentioned in the Navy books will object, but in
terms of do-ability this has been the preferred method for decades.

Tim.