After 20+ years of faithful service (please forgive the pathetic fallacy), my NAD MR-20 has started having problems (which I'll get to shortly).
In the late '80s, NAD (New Acoustic Dimension) and Proton started making high-quality color TVs, in an attempt to take market share from Sony who (from my point of view) was the only company trying to deliver a consistently good picture.
The MR-20 was a success (you might still be able to find my review on the Stereophile site), and I suspect thousands of them are still in use. It is _absolutely_ a classic color TV, one of the first to take on Sony and beat it at its own game.
This particular MR-20 was purchased in the late '80s, not long after it was introduced. It's actually an MR-20a, the modification being an improvement to the comb filter that reduced the visibility of "hanging dots". The set has roughly 20K hours on it (frightening!), and until now had only one problem, a bad cap on the video driver board.
A few weeks ago it abruptly began showing drops in brightness along with a loss of sharpness. Since then, it has more or less stabilized. It now takes about 5 to 10 minutes for the CRT to come to full brightness, after which the picture is generally good, with occasional losses of brightness & sharpness, or a slight "flickering" of the black level.
It's not clear what the problem is. It could be a bad HV rectifier, more bad caps on the driver board, or even a failing CRT. Not surprisingly, parts are no longer available.
I've decided not to make any effort to fix the MR-20. It's my home-office set, and I can substitute an old Sony 13" for it. (Perhaps next year I'll buy a 26" Vizio. You should see the new 52" Vizio -- outstanding picture, and dirt-cheap.)
The cabinet is in excellent condition. The only cosmetic "problem" is that the sheet of plate glass protecting the CRT disintegrated several years ago. (That's an interesting story in and of itself.)
The MR-20 wasn't cheap, but it's given so much service I could toss it without thinking twice. However, I'd rather sell it to someone who collects classic TVs. Though I normally keep cartons for everything, the MR-20 carton is long-gone, and it's a heavy set that isn't easy (or cheap) to ship safely.
If anyone is interested, please contact me directly. I'll be happy to supply photos and any specifics.
Thank you.