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Main => Monitor/Video Forum => Topic started by: neokidgeo on February 17, 2008, 10:14:07 am

Title: Sanyo monitor picture missing colour
Post by: neokidgeo on February 17, 2008, 10:14:07 am

Hi guys,

I've fired up one of my namco bootleg cabs with a board in it and i got pic's but when i turn the screen up i get red raster lines, Any ideas guys  ??? i can see any model number anywhere only part numbers so heres a pic hope that helps ident  :)

Thanks guys
Neo

Title: Re: Sanyo monitor red raster lines only
Post by: grantspain on February 17, 2008, 10:44:53 am

if you have a actual picture with red flyback lines then you red background is too high,locate the red adjustment and turn it down
btw thats the most connector block i have seen on a monitor ;)

Title: Re: Sanyo monitor red raster lines only
Post by: neokidgeo on February 17, 2008, 12:09:40 pm

Hi grant,

This is what i'm getting after turning all the controls up full apart from the green drive that the neck board don't have  ???

Title: Re: Sanyo monitor picture missing colour
Post by: grantspain on February 17, 2008, 12:17:23 pm

i can't see the blue,how many controls do you have for the colours?

Title: Re: Sanyo monitor picture missing colour
Post by: neokidgeo on February 17, 2008, 12:22:58 pm

I have green,blue,red then red drive and blue drive but there seems to be no green drive pot or markings where there should be one.

Title: Re: Sanyo monitor picture missing colour
Post by: grantspain on February 17, 2008, 12:28:46 pm

http://therealbobroberts.net/sanyo.html
this is your monitor
most monitors do not have a green drive
turn down the backgrounds to about quarter way,then turn down the red and blue drive to match the green then bring up contrast and brightness
like i said i can't see any blue,you need to prove the blue is present

Title: Re: Sanyo monitor picture missing colour
Post by: neokidgeo on February 17, 2008, 01:49:59 pm

Did what yu said grant but didn't change so i turned the cotrols down and turn them up one at a time and this is what i got, Green and red turn up and down nice but the blue pot only starts working 3/4 way round.

Green, Blue, Red

Title: Re: Sanyo monitor picture missing colour
Post by: grantspain on February 17, 2008, 01:59:45 pm

got this bad feeling your tube is bad on the blue gun
you could swap out the blue and red drive transistor to prove it not a bad transistor

Title: Re: Sanyo monitor picture missing colour
Post by: neokidgeo on February 17, 2008, 04:10:40 pm

Swaped over but no luck  :cry:

Title: Re: Sanyo monitor picture missing colour
Post by: grantspain on February 17, 2008, 04:27:56 pm

i would like to see what ken and qrz say about this as i am convinced your tube is a gonna,it would be good to get a second opinion.
i hope i am wrong but i don't think so :(

Title: Re: Sanyo monitor picture missing colour
Post by: neokidgeo on February 17, 2008, 04:44:03 pm

Thanks for your help grant  :notworthy:

Title: Re: Sanyo monitor picture missing colour
Post by: neokidgeo on February 18, 2008, 03:18:25 pm

Quick update the tube is good, I tried the chassis on a diffrent tube i have and the picture was the same, The connector blocks hide a few hacks, The rgb sync and ground wires from the loom are soldered to resistors and the blue from the chassis to the neck board was soldered to a resistor on the chassis, I de soldered and put the blue back to where it should be and the blue on screen was a little bit stronger but not enough  :cry: o well hunt for a replacement chassis starts but does anyone know the model of it?

Thanks guys
Neo

Title: Re: Sanyo monitor picture missing colour
Post by: grantspain on February 18, 2008, 03:49:23 pm

well thats good news and a good bit of detective work,in this scenario it would be wise to start comparing the different colour lines with a multimeter or swap out pots,caps and resistors also check the board tracks for breaks

Title: Re: Sanyo monitor picture missing colour
Post by: Ken Layton on February 19, 2008, 02:49:16 am

Quote from: neokidgeo on February 17, 2008, 10:14:07 am

Hi guys,

I've fired up one of my namco bootleg cabs with a board in it and i got pic's but when i turn the screen up i get red raster lines, Any ideas guys  ??? i can see any model number anywhere only part numbers so heres a pic hope that helps ident  :)

Thanks guys
Neo

What the hell happened to that chassis? What's that mess of wires? That looks horrible.

Has this chassis been recapped and solder joints checked?

Title: Re: Sanyo monitor picture missing colour
Post by: neokidgeo on February 19, 2008, 01:44:02 pm

Hi ken,

I will have a look when i get home, Yep its got more wires then radio shack, it's been badly repaired and it looks new almost  :dunno
I been trying to find a model number but i've had no luck just part numbers that come up with nothing on google.
Wil report back  :)