Sanyo monitor picture missing colour

[neokidgeo]

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

[grantspain]

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

[neokidgeo]

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 

[grantspain]

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

[neokidgeo]

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.

[grantspain]

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

[neokidgeo]

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

[grantspain]

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

[neokidgeo]

Swaped over but no luck 

[grantspain]

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

[neokidgeo]

Thanks for your help grant 

[neokidgeo]

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  o well hunt for a replacement chassis starts but does anyone know the model of it?

Thanks guys
Neo

[grantspain]

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

[Ken Layton]

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?

[neokidgeo]

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 
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