Home |
Search |
Today's Posts |
|
Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#1
Posted to sci.electronics.repair
|
|||
|
|||
projection tv
Not to take too much of your time, here's what happened:
I took my magnavox projection tv rear off to clean the guns and the mirror. While wiping it out I hit the color adjustment knobs in the back. I tried to "fix" it and obviously it got worse. Is there a "trick" to setting the colors? I got pretty close by trial and error, but there is too much yellow and skin tones are crappy. I've googled this to no avail. Is there a set way to adjust the gun's colors to get it right? This is inside, not the color adjustments via the remote menu, just to clarify. Thanks to all in advance and for reading this far. |
#2
Posted to sci.electronics.repair
|
|||
|
|||
projection tv
Trick is to set the brightness at factory default, usually 50%. Then
turn down the color all the way. Recieve normal video and cut the picture control down until you can just barely see the picture, then, if you have to do it in the back look at the lenses, or their reflections in the screen. Try to equalize them at a barely seeable level. When you have the room dark and have a dark picture that looks pretty much black and white, that is not overly tinted, then turn the picture control to maximum. Note the color of the bright parts of the picture at that time. Then you need to turn down the drive control for that color. It could be a pot or it could be in software. Just what year is this thing and what make and model ? And where are you geographically ? Not that I'm coming over, but I want data on what kind of different repairs are needed more often in different climates. It is very possible that your blue tube has bad coolant. Red plus green plus blue make white, take the blue away you have yellow. Very common in certain brands. Also in certain brands the blue is pushed alot harder. In Sonys especially, the blue is the hardest driven tube in it, and the reason is that they use a different phosphor. It is not as efficient, but it emits a very deep, pure blue color, somewhat like comparing sky blue to midnight, or Navy blue. It is a deeper, truer blue. Like I said, what is the make and model of this thing ? Without that I can go on for hours but there is no point. JURB |
#3
Posted to sci.electronics.repair
|
|||
|
|||
projection tv
There are normally two sets of adjustments -- Screen and Drive. Broadly
speaking, the Screen control adjust the darkest areas of the picture, the Drive the brightest. (There is usually no red Drive control, because the red phosphors are/were the least-efficient, and were run "at full blast". Looking at a monochrome image (play "Casablanca"), you need to adjust these controls to get a neutral (colorless) image. Try Googling "gray-scale tracking" + "crt". |
#4
Posted to sci.electronics.repair
|
|||
|
|||
projection tv
wrote in message oups.com... Trick is to set the brightness at factory default, usually 50%. Then turn down the color all the way. Recieve normal video and cut the picture control down until you can just barely see the picture, then, if you have to do it in the back look at the lenses, or their reflections in the screen. Try to equalize them at a barely seeable level. When you have the room dark and have a dark picture that looks pretty much black and white, that is not overly tinted, then turn the picture control to maximum. Note the color of the bright parts of the picture at that time. Then you need to turn down the drive control for that color. It could be a pot or it could be in software. Just what year is this thing and what make and model ? And where are you geographically ? Not that I'm coming over, but I want data on what kind of different repairs are needed more often in different climates. It is very possible that your blue tube has bad coolant. Red plus green plus blue make white, take the blue away you have yellow. Very common in certain brands. Also in certain brands the blue is pushed alot harder. In Sonys especially, the blue is the hardest driven tube in it, and the reason is that they use a different phosphor. It is not as efficient, but it emits a very deep, pure blue color, somewhat like comparing sky blue to midnight, or Navy blue. It is a deeper, truer blue. Like I said, what is the make and model of this thing ? Without that I can go on for hours but there is no point. JURB Thanks for replying double Z. Here's my model: http://www.walmart.com/catalog/produ...uct_id=2601133 It's a 51 inch magnavox. I know the blue gun is going bad as the picture has a blue offset in the lower left and opposite right top corners. The color was fine and after being unable to fix the blue via remote so I figured a little cleaning wouldn't hurt. I carefully wiped out the dust in the back. I hit one of the guns color knobs though and knocked the color a little off (to this point it was fine). I thought I'd just twiddle it back to where it should be and it's one of those things that just gets worse the more you "fix" it. As to the coolant, it looked quite clear looking into the guns, but I was surprised how dusty and filthy the inside of those things get. It should be more user serviceable if it funks up that fast. (and we are clean people with no animals too) BTW I'm in coastal Pacific Northwest. You ever pass down 101 along the coast and I'll treat you to the best crab and clam you'll ever eat. |
#5
Posted to sci.electronics.repair
|
|||
|
|||
projection tv
"William Sommerwerck" wrote in message . .. There are normally two sets of adjustments -- Screen and Drive. Broadly speaking, the Screen control adjust the darkest areas of the picture, the Drive the brightest. (There is usually no red Drive control, because the red phosphors are/were the least-efficient, and were run "at full blast". Looking at a monochrome image (play "Casablanca"), you need to adjust these controls to get a neutral (colorless) image. Try Googling "gray-scale tracking" + "crt". That makes sense because my black and white color is screwed up too. It's a weird brown/grey. Tonight I'll get the info and get cracking. Thank you!! |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Projection Lamp for projection TV | Electronics Repair | |||
LG Projection T.V. | Electronics Repair | |||
Projection TV | Electronics Repair | |||
RCA Projection TV | Electronics Repair | |||
RCA Projection TV ? | Electronics Repair |