Dude111
10-05-2009, 07:17 AM
I remember in the 80s and before when BW stuff was shown on many channels,it had a slight red fence over it (Reddish dots all thru the screen) it made it nice to watch!
Not every channel had them when they showed something BW but most did.. Now NONE OF THEM HAVE IT,it just a flat BW pic and doesnt look as good...
What did they do to stop these reddish dots? (I believe it has something to do with the colour modulation being left on during a BW event but im not sure)
I wish channels would start doing that again,it made stuff even nicer to watch in my opinion!
Phil Nelson
10-05-2009, 10:54 AM
Just guessing, but perhaps your TV wasn't working quite right. A color TV with misadjusted convergence can show color fringing -- red, green, blue, or some combination -- during a B/W broadcast. This can be extreme or very slight.
Other causes might be misadjustment of the TV's "color killer" circuit, which turns off color for B/W material, or gray scale tracking, which balances the three R-G-B colors to produce a perfect gray (or white or black) when that's called for.
When I read old TV books, it's clear their goal was that black and white programs would look black and white on a color TV, not "enhanced" with any other color. This must have been especially important in early days, when most shows were still in B/W.
Or, I could be all wet. I don't know why broadcasting a B/W program as color would make it look colored. If you look at a portion of a color picture with a large B/W area, that looks black and white to my eyes.
Phil
ChrisW6ATV
10-06-2009, 12:26 AM
I can see how a B&W program could have color "dots" on the screen, if the color subcarrier was still broadcast on the channel and/or the color killer was not working on the TV, especially if the color control was set relatively high or the signal was weak. All of this would be considered problems, though; I never thought of color on a B&W show as enjoyable.
One exception: When I first got to operate a color TV myself, in a hotel in the 1970's, its color killer was bad, and so the channels with no signals had full-color snow. I thought that was really cool, and I was disappointed later when I found out that TVs normally don't work that way. (I had not even heard of the color-killer circuit yet.)
Dude111
10-06-2009, 08:09 AM
Ya that had to be it,the colour subcarrier left on when it should have been off....
I remember watching the munsters this way as well as many others...
It was nicer in my opinion,i dunno.....
compucat
10-06-2009, 11:11 AM
My Zenith roundie has a switch on the color control to turn off the color during a black and white program. I guess to overcome this very problem. Come to think of it, I don't believe the 25MC33 chassis has a color killer circuit. I don't remember such a control when working on the set.
Dude111
01-10-2013, 03:01 AM
I wonder if you turned it on during a BW show if you would see what im referring to? (Would be interesting)