I've been wondering for some time if there is any need for beam-convergence adjustments on today's flat-screen TVs. Since these sets do not use CRTs, I wouldn't think so, but I am very new to flat-screen technology (just got my first FP this past August) and have absolutely no clue as to how these things work or service adjustments for convergence, sweep, etc. My set works perfectly; I'm just curious as to how one would converge a FP, adjust the sweeps, and so on. Or are these adjustments all made at the factory and permanently fixed into position (by cementing the controls or by using fixed resistors, etc.), so that they absolutely cannot be altered -- even by a technician? :scratch2:

TIA

If your talking about modern LCD, DLP or plasma the answer is NO! There is nothing to converge. These have pixels rather than lines. No sweep circuits either.

Most Plasmas and LCD's do have adjustments in the service menu for gray scale, width, height, overscan and a lot of other stuff the average owner should avoid.

The one handy feature on most new sets is an hour meter, you can find out how long your set has been run and how many times it's been cycled on & off.

Good to know if you are thinking about buying a used one.

My set was a Demo at Circuit City and had 800 hours on it when I got it, I didn't check it until I got home however because finding out how to get to the counter can be difficult/impossible without instructions

Recently I find at the dump a Samsung WS-32Z316V Slim set, I don't know the deflection angle of that CRT but need convergence :smoke:

If your talking about modern LCD, DLP or plasma the answer is NO! There is nothing to converge. These have pixels rather than lines. No sweep circuits either.

It's just as well, since converging a standard NTSC CRT set isn't what I would call an easy task (in the 1970s I had a Silvertone roundie, RCA CTC12 clone, on which the convergence was way off; never did get it right in the three years I had the set). The absence of sweep systems in today's FPs also means two fewer circuits to cause problems.

What's next -- a TV with no circuitry at all, just the panel? :scratch2: I think today's flat sets are very close to that point already. I cannot imagine how an entire TV can be fitted into a cabinet as slim as most of today's FPs are (I don't think today's flat sets are more than an inch or so thick). Of course, the absence of the traditional CRT shaves quite a bit off the front-to-back measurement and the weight of the set, and LED backlighting of almost all modern FPs means no space is required for a large incandescent backlight bulb or CCFL (cold-cathode fluorescent lamp); no need for a power source for such a bulb, either. No worries over replacing the backlight bulb as well. At $200+ apiece, these bulbs are not cheap (to say nothing of sky-high repair costs, since incandescent backlights were not intended to be replaced by the set owner), so it is no wonder these older HDTVs are being replaced by modern FPs when the old sets develop expensive repair problems. No different from CRT sets made from roughly 1980 to the end of the NTSC era.

It's just as well, since converging a standard NTSC CRT set isn't what I would call an easy task (in the 1970s I had a Silvertone roundie, RCA CTC12 clone, on which the convergence was way off; never did get it right in the three years I had the set). The absence of sweep systems in today's FPs also means two fewer circuits to cause problems.

What's next -- a TV with no circuitry at all, just the panel? :scratch2: I think today's flat sets are very close to that point already. I cannot imagine how an entire TV can be fitted into a cabinet as slim as most of today's FPs are (I don't think today's flat sets are more than an inch or so thick).

Check this out... DTVs have plenty of circuits, and likely millions of transistors, shrunk down to several very complicated ICs.

http://www.eetimes.com/design/power-management-design/4013346/The-basics-of-HDTV-A-behind-the-screen-look-at-TV-technology

Perhaps someday, the fabrication of the ICs will advance to the point of having "one big chip", and perhaps that chip could be fabricated on the display panel to make a "circuit less" set... but indeed, there will still be lots of circuits.

jr

Remembering Moore's law for the number of individual transistors per integrated circuit(chip) doubling every 2 years, the new panels have an astonishing amount of functions in their 'wafer-thin' cabinet...and can be quite precise WRT things like convergence, positioning, and brightness levels of each pixel. BUt if you ask me, the repairability of surface mount componentry is prohibitively annoying,and i like my displays to be user servicable as it were.