[ARC5] What is it? BC455 variation?

[Russ Schroeder]

Was playing around with a couple of ARC5 receivers today and discovered
something new to me.

I have a modified receiver (not by me!) that from the front looks like a
BC455. The front panel is black wrinkle, however, the chassis is painted
gray (over black). There is a 3/4 inch square black stamp on the right side
with a black border with the following inside the border "PEN"  "8-57"
"(smudge)2".  In addition, there is a red stamp above the black one which
reads "9 OH 8 57". No other identification on the chassis. The top cover is
missing. The main item that caught my interest is the IF transformers. They
are DOUBLE tuned. In my limited knowledge base, I have only seen single
tuned IF transformers on the 6-9 Mc receivers. The four digit part numbers
on the IF cans are "9693", "9697" and "9699". In addition, several of the
can capacitors underneath have what looks like ceramic tops rather than the
expected Mica. Anyone have any info that they would care to share?

Russ W2DYY