[Hallicrafters] Question: Tropicalized Halli receivers?

[Tom NØJMY]

Are any of you familiar with "tropicalized" Halli receivers?

This evening I was going through the parts list for the S-20R and found 
there was a couple pages of substitute parts to be used in 
"tropicalized" units.  Of particular interest to me was a dozen or so 
paper caps of different values.

My curiosity gets the better of me.  What is a "tropicalized" S-20R? 
Were they common at all?  Is there any quick way to identify one, short 
of opening it up and checking the components?

Thanks in advance for any info you might have.

73,
Tom NØJMY .   .

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