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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Jose on December 24, 2005, 01:38:11 PM
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Hi. Some TV's/most monitors (when using VGA with AGA or ECS), don't have color control. How can one boost the RGB signal to have more intense colors for in my Nokia 446Pro monitor and my TV the color intensity is too weak and they don't have color controls (TV does have it, but it doesn't work with RGB Scart connection).
I thought about opening the TV and messing with the color amps on the tube but, besides being extremely dangerous, I fear screwing up the tube's settings and not being able to put them back.
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all RGB inputs (both video and VGA) doesn't have saturation controls (as you already know)
Now, it depends on how your TVset/monitor is designed you don't have controls over the single components in INPUT.
If you rise the RGB gain, ALL the the RGB signals will be raised as well.
If your TV its only used with your Amiga it worth to try.
Use this SPG (Signal Pattern Generator) to check at least, the white balance.
MonitorTest (http://ftp://de.aminet.net/pub/aminet/util/misc/MonitorTest.lha) on Aminet
Good luck :-)
EDIT- ah . . . if you have a screen promoter installed (NewMode or so) disable it (or at least select Promote=NO, for the MonitorTest task)
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"Good luck :-)"
Yeah, I hope I don't get fried :-o :-) I'm really tempted to do it. I'll open the TV and see if I find any info on the tube's settings on the net...
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Try to rise the RGB signals BEFORE the JOKE(?) (if present)
Don't touch the joke trimmers at all (usually theese are the cutoff trimmers)
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Jose wrote:
I thought about opening the TV and messing with the color amps on the tube...
If you try that you will [color=ff0000]_DIE_[/color][/b] of a 50,000 volt shock.
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Try to rise the RGB signals BEFORE the JOKE(?) (if present)
That will be the YOKE that you are talking about ;-)
The Yoke is the back of the tube where the connections are.
If you are not familiar with the innerds of a TV, stay well clear. Also a lot of modern TVs have no internal adjustments that are of any use. There may be RGB gain controls on the board on the back of the tube if you are lucky, but if you do not know how to recognise them, don't twiddle.
The board on the back of the tube usually has at least 1000 volts going though it, (which is nothing compared to the 27 THOUSAND volts going to that rubber sucker that us techies call the anode cap)
Scared yet ? You should be
:-o
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@amigaoneproductions
"If you are not familiar with the innerds of a TV, stay well clear."
I'm not. :-)
" Also a lot of modern TVs have no internal adjustments that are of any use. There may be RGB gain controls on the board on the back of the tube if you are lucky, but if you do not know how to recognise them, don't twiddle."
Mine is not modern, it's a 15 year old Sanyo. But I was told by the technitian that last repaired it, that it has a processor that controls inputs or something. Not sure it it has RGB gain. Nothing like opening to see.
"The board on the back of the tube usually has at least 1000 volts going though it, (which is nothing compared to the 27 THOUSAND volts going to that rubber sucker that us techies call the anode cap)
Scared yet ? You should be"
Cool!! :-D Seriously, of course I am, I don't plan to keep the TV on or even plugged into mains when I'll open it.
If there's another way around it let me know...
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I don't plan to keep the TV on or even plugged into mains when I'll open it.
STOP !
TV's hold a high voltage charge for HOURS after being unplugged. Working on them just unplugged is not enough, the tube has to be discharged to make it safe. I am deliberatly not telling you how to do this as I don't think you should go anywhere near. I do this stuff for a living and have been doing this sort of stuff for years, and there is no way I would allow one of my collegues to work on a monitor or TV without the proper training.
It is not DIFFICULT ro work on these things, but I cannot encourage you to go poking around without knowing exactly what you are doing.
What I would suggest is asking if there is anybody nearby you with the required expertise, where abouts on the planet do you live, (this being a global forum ;-) )
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I did not make myself clear the first time.
Jose wrote:
I thought about opening the TV and messing with the color amps on the tube...
If you unplug your TV and leave it unplugged for 2 solid weeks so the voltage can slowly leak away then when you open the TV and and try your idea you will [color=ff0000]_DIE_[/color][/b] from 30,000 volts of electricity that jump out of the TV and into your body.
At least you won't have to worry about ever debugging your semaphores again.
Please notice there are no smiley faces in my messages to you.
BTW: before you try to fix your TV would you please send me all your Amiga stuff?
I don't want it to be buried with you.
Amigas should be preserved forever. Thanks.
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Guys, thanks for your concerns really!! I'm aware of the danger and I'm not gonna do anything silly. If I open it and find out that it has some obvious settings like r, g and b gain you can be sure I won't try to change them without being HYPER properly isolated.
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@Jose
I'm aware of the danger and I'm not gonna do anything silly.
Thats good to hear !
@ChaosLord
Another soul saved, I think we have done our good deed for Xmas :-)
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"Another soul saved, I think we have done our good deed for Xmas :-) "
:lol:
:pint:
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ChaosLord wrote:
when you open the TV and and try your idea you will [color=ff0000]_DIE_[/color][/b] from 30,000 volts. Thanks.
Best to believe that on a colour tube it's [color=ff0000]just [/color] 27 kV :-D
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Hi. After a few hours search the other day I found RGB booster (http://web.ukonline.co.uk/unique72/rgbbooster.htm)
Do you guys know of any similar circuit ? What's the result like is there a degradation in image quality ?
P.S.
No, I still haven't opened my TV, once people here finishes vacation I will do it ( so I still have a couple of days to live..:roll:)
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No, I still haven't opened my TV, once people here finishes vacation I will do it ( so I still have a couple of days to live.
One of the rules of TV repair: Never work alone, that way if you do get fried, there will be someone to call the emergency services :-)
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Maybe this would also be a good read :
Ten Commandments of Electrical Safety (http://siri.uvm.edu/ppt/electric.html)
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btw: if you turn up all R, G, and B amps, you'll get a brighter picture and nothing else...
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What I need is another TV..
I think I'll leave it, not worth the time, I probably won't be able to do anything...
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the best thing to do! IMHO :-)
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<<<>>
actually you can't die 'cause there is no Amps but you will have a REALY painful SOCK.
ofcourse if you have cardioid probs then dying is an option...
As a careless profesional in this things I was shocked many times because I was careless when discharging the anode cap...
But I assure you... I NEVER got used the sock!!! and at 2 circumstances I cut badly my hand on the case...
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Pffft... girlymen...
I've been nuked by a 1950 tube and by a 1960 tube in the past. It won't kill you unless you are unfortunate enough to bang your head on the corner of the bench/table as you fall on your arse. (But perhaps your TV has a bit more oomph than the 1950/60 if you're in europe?)
I recommend the following: a long screwdriver so you don't accidentally touch anything with your hand/arm (only hold onto the handle, not the shaft), and wear rubber soled shoes so you aren't vertically grounded, then, put a nice mat down on the floor so if you get a suprise you at least have a soft landing.
As my local Commodore repair center tech once said, "Well it won't kill you, but you'll probably have a nice little nap if you accidentally touch that." :lol:
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And for (insert deity of choice here)'s sake, take your feckin watch and rings off before you go prodding around inside there! :lol:
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Great! :lol:
There was a time in my father's life, around 30 years ago when he fixed very old CRT's. He once toutched one that was on and got knocked inconscious for like 10 minutes :-o