[UberVacTuber]

Hi all,

This is my first post, so here goes.. I'm working on a 1948 Admiral 30A1 10" set. I've recapped the chassis and replaced a lot of bad resistors (some were tricky to disconnect to be tested, so I ended up replacing them, so the horizontal and vertical sections look "shotgunned"). I replaced a few weak tubes and after running the set for over an hour I rechecked the tubes and found a few more that were giving up. I get a picture and sound, and for the most part all the controls effect the picture or sound they way they are supposed to. However, I have a few bugs I've been working on. Some may be inherent to the design of the set, while others might be more a function of the video source (VCR and DVD player). I'll list the issues and see what you guys think (This is my first TV project, so bare with me!).

1. When I turn the Contrast dial, as the contrast decreases I noticed that the sound volume also fades. The Volume control is on the adjacent control, so it is not being caused by the outer dial dragging on the inner dial and turning it.

2. What is the proper distance that the focus coil should be from the deflector yoke? When trying to center the picture, I got the focus coil way out of whack as I didn't know at the time that the coil has to be angled opposite the way you want the picture to go. I backed it off to unload the tension springs so I could wiggle the coil by hand, and now even though I've tightened it back up, when I adjust the ion trap for the brightest picture the lower right corner of the raster is rounded off. It looks like I need to move the coil back in, but I wondered if there is a specified distance.

3. The raster has way too much width and the horizontal linearity is off. When the width adjustment coil is backed all the way out, you can just see the right-hand edge of the raster. If you screw it in at all, the right-hand edge also moves off the screen. Also, the horizontal linearity coil seems to have no effect on the picture. I went through all of the HV section, cleaning contacts and checking resistors to look for anything amiss. The Ryder manual mentions that "Tube aging (Which tubes?) may make horizontal linearity adjustment impossible" and that you can change the tap on the damping resistor to potentially remedy this. Interestingly, when powering up the set with a variac, you can see both the left- and right-hand sides of the raster until you get up to almost 90VAC, and then the left side moves off the CRT scren as the raster grows.

4. In many instances, there are thin diagonal white lines that cross over the picture. Are these retrace lines? I remember a thread here where someone mentioned that with Admirals of this vintage this may be normal. What gets me is sometimes they really stick out, other times you don't see them...

Anyway, this ought to be plenty to get started with. Thanks!