[Ron Ramirez]

At first I thought that the one round aluminum tube shield had to be a non-original replacement. But in my search for chassis pictures I found the same round aluminum tube shield on most of them! Another clue: note that the tube shield base of the 6U7G (rearmost tube on the RF subchassis) is aluminum rather than plated tin like every other Philco tube shield on this chassis - or any other that I've seen. So I believe it's original (although was initially sitting on the wrong tube on mine). It's not called out in the parts list of the service bulletin. Perhaps someone here knows the answer to this riddle??

It is original. Why did they do this? I don't know. You would have to ask a Philco engineer of the time - and he won't answer, because dead men tell no tales.

Oh, and good luck with that RF unit. I hope you don't have the trouble that I did with the 38-690 I used to own. I went through three RF units before finding one that would work. Since you're already receiving the AM band, though, you're ahead of the game.