bigaudioal
12-21-2020, 09:05 AM
A few months ago, I had a customer drop off a very nice Stromberg Carlson TC-19 "New Yorker" for restoration. I had the SAMS and went to town on recapping it. I got around to testing the CRT and it was on the weak side. Zero cutoff and low emissions. Would definitely make a picture though, so I continued with the restoration. The owner had done some work on it, replacing the VOT and yoke b/c he had no vertical deflection . . . stuff owners typically do to try and get a quick fix without investigating the vertical circuit further. But I was pleasantly surprised this past weekend when I powered it up and got a decent image and great sound. The picture is backwards horizontally (text appears backwards when on screen), and thinking this is a simple crossed wiring of the horizontal section of the yoke by the owner, since he was messing with it. I need to investigate further, but otherwise decent and pretty solid operation for 2 plus hours with no obvious hiccups.
The CRT is definitely weak and the attached picture of the set working is with the brightness and contrast all the way up. So I wanted to let the owner know that he may want to be on the lookout for an available 19AP4 . . . record scratch noise!!!!!!
It was then I first noticed the base socket of the CRT says 16AP4A. All the literature I can find on this set says it uses a 19AP4. I guess I just did not notice the "6" instead of the "9" on the base socket. CRT testing settings are the same for these two tubes, so I know I got an accurate test. It sure looks like a 19AP4 and all the CRT mounting hardware in the cabinet sure looks original and unmodified. I can see no signs of alterations for a smaller CRT. I am almost certain this is a 19AP4 in disguise!!! I have restored several 19AP4 sets in the past, so pretty familiar with this tube and its size.
Guess I could always remove the CRT and measure the face to be totally 100% sure. I was thinking, is there a chance that this tube was either rebuilt and the wrong base socket was installed? Or more simply, the original base socket broke and was replaced using the wrong base socket? Anyone ever heard of a situation like this? Strange.
The CRT is definitely weak and the attached picture of the set working is with the brightness and contrast all the way up. So I wanted to let the owner know that he may want to be on the lookout for an available 19AP4 . . . record scratch noise!!!!!!
It was then I first noticed the base socket of the CRT says 16AP4A. All the literature I can find on this set says it uses a 19AP4. I guess I just did not notice the "6" instead of the "9" on the base socket. CRT testing settings are the same for these two tubes, so I know I got an accurate test. It sure looks like a 19AP4 and all the CRT mounting hardware in the cabinet sure looks original and unmodified. I can see no signs of alterations for a smaller CRT. I am almost certain this is a 19AP4 in disguise!!! I have restored several 19AP4 sets in the past, so pretty familiar with this tube and its size.
Guess I could always remove the CRT and measure the face to be totally 100% sure. I was thinking, is there a chance that this tube was either rebuilt and the wrong base socket was installed? Or more simply, the original base socket broke and was replaced using the wrong base socket? Anyone ever heard of a situation like this? Strange.