Thanks, and that’s correct, and I am well aware. However, I have never seen a 7730 labled CBS. All the 7730’s I have owned in the past (3 pairs), and have seen in pics have been labled Raytheon, so that’s why I put that in the title. Now, when it comes to the 7728, and 7729, I have both CBS and Raytheon labled tubes, and they are all made by CBS.