SP600-JX21 and later had no black beauty tubular caps. I had a JX14 and it still used them in the turret and the rf deck. Everything under the chassis was bathtub caps mounted on the sides of the under carriage.
FYI
Thanks. I remember replacing the tubulars in the RF strips of a couple of SP-600's several (OK, many) years ago, and don't look forward to ever doing it again. The SP-600 is my favorite SWL receiver, and if I can find a JX-21 (or later) one locally, I'd be a happy SWL.
Thankls again....