What are lines on my CRT?
 

I had to start using a new converter box on my Analog RCA Set. The box I have is a LasonicTA260 Converter Box. I have a really nice picture but have one issue. If you are close enough to the CRT you can sometimes see red& green vertical lines in dark backgrounds. I remember using this same box on another RCA Set of about the same time era & it had those same lines on it. I didn't have these lines when I used my previous box that quit working.

Anyone that would know what is causing this or what I can do to remove these lines would be appreciated. :scratch2:

Could be the Video RAM chips in the converter starting to go bad......

For your next box aim for one that runs cool..... Like a Zenith/Insignia.

The lines on your CRT may be test signals or closed-captioning, Macrovision, etc. If you are seeing them (you shouldn't), your set might be underscanning somewhat.

For converter boxes, I agree that they can run warm or downright hot. These boxes probably have components just barely large enough (in capacitance, physical size and resistance) to do the job. Needless to say, boxes built using these cheap parts will run hotter and will fail a heck of a lot sooner than those with conservatively-rated or overrated components. I have a "Windsor" brand clock radio in which the components are crowded together in a very small case. I've had this radio for about ten years; it still works, though I'm darned if I know why, as crowded together as the components and power transformer seem to be, looking through the ventilation slots. I would think the heat from the transformer would have done some damage by now, but to date it hasn't, or if it has I haven't noticed it.

I agree on Zenith/Insignia. I have an Insignia 19" flat-panel TV that runs cool, no hot spots on the cabinet. Their converter boxes are, from what I've read, built to outlast those offshore-built Apex, et al. units that often burn up after only a short time.

Reread - the OP said vertical lines. Test signals, closed captions, etc. produce a few bright horizontal lines at the very top of the picture. This is something else.

Are these vertical lines faint? Do they change with image content or are they stationary?

If stationary, they are most likely the box.Different converter boxes used different techniques for converting the HD broadcasts down to SD for the analog output, and this brand may have less accuracy than some others.

If they move with changing content, it could be the box or conceivably the station's MPEG encoder. Is it the same on all stations?

A picture of said lines would be great.

Here's a little more interesting info on that converter box issue. I have played around with it using both a push on coax cable, a screw on terminal cable, and even and old 300 ohm flat wire with the clothes pin hookup. This is going to sound crazy but with the old 300 ohm wire I have the least background interference on my CRT. The most interference on my CRT comes from the screw on terminal coax cable. When I push on the terminal of the converter box that you hook your wire to that goes to the back of your set if you push and wiggle it sometimes does away with the interference. :scratch2:

You may have a loose internal connection in the box or the TV connection points. But total tight integrity of cables is very important for a good picture without interference. Try another screw-on cable, just long enough to reach. I've found a difference in the quality of some cables and their connectors. Also try tightening the connector with a wrench, just snug, tighter than finger tight but don't kill it. Sometimes tightening makes bad things go away.