Hash keys are stringified. When you used the file handle reference as hash key, perl turned it into a string representation of the reference. The reference itself is gone!

Perhaps a hash wasn't the right choice for your data structure. Since all you're doing is iterating over your data anyway, perhaps an array of arrays (AoA) would be more useful. Untested:

# Somewhere earlier...
my @radar = ();
push @radar, [$fileh, $repoch] for (1..5);

# ... then:
for (@radar){
   my ($fileh, $repoch) = @$_;

   # ... continue as before.
}
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