quick question about blank screens

[crimsonghost]

My tv says "unusable signal" when nothing is plugged in. When i turn on my v7 ps2 with messiah 2 it still says "unusable signal" would that be the equivilant of a blank screen? Thats what i treated it as, I checked ever damn soldier joint on the messiah2 and connecting wires and joints close to it no bridges and all the wires have good connections.

[crimsonghost]

my boss just came over and double checked my work, he could find no errors bridges or soldier balls so any help would be greatly appriciated

[crimsonghost]

quastion about points D - I if you follow the soldier point traces you will come to some via's should all of them read 0 ohm's on a conductivity test? DEFI are, but GH are not so there is not direct connectivity with the via's but I am getting a reading

[Bgnome]

you should get 0, but sometimes theres a bit of laquer on the via so you need to make sure you have a clean contact if you are checking resistance/continuity..

[crimsonghost]

well it seems i was off by 1 via on gh i double checked they are both at 0 ohm's....I guess there is nothing left but bridge/balls are damaged component just gonna back out of the install and see if the board will work

[kgn3402]

i had the black screen one after an install. there are two things that i think may have caused it in my case:

1) running the board without proper heat-sinking. This would have caused the CPU & other IC's to burn out. I think some people have had this happen when they run there system for a while, and then ... black screen. Because the heatsinking wasn't properly mounted, one or more chips burned themselves up.

2) Another possible scenario for me was using a 60Watt soldering iron on the BIOS chip. All posts say use a 15Watt. Well, I tried with a 60Watt being extremely careful to hold the tip for only a fraction of a second. But who knows ... maybe I toasted the BIOS chip with my HOT soldering iron.

I have since replaced my faulty unit. I am up an running now with a Magic2 in a V7. These are the precautions that I took over my previous install:

[kgn3402]

As I was saying ... here are my precautions:
- never run unit with out proper heatsinking
- when sandwhiching the motherboard, make sure the heatsinking material is making GOOD contact
- never use a HHHOTTTT soldering iron. I used one with a temperature control dial, so i was able to be very careful.

I hope that this might one day help someone in the future.

-kev

[crimsonghost]

I have a weller adjustable not too sure how many whats, but any idea on what the maximum temperature i should use ?

[kgn3402]

One last thing ...

Some people when swear on a stack of bibles that Black Screen are caused by SOLDER BRIDGES. well, I scrutinized my work with a 16x magnifier. There were NO bridges.

I know that other people have had repairable solder bridges in the past, but for me ... it wasn't the culprit.

-kev

[kgn3402]

I can't remember the acutal temperature i used. you can look up a melting temp for solder on the internet and set it slightly higher than that. OR, just test your solder with the iron until you find an appropriate temp.

you will need a temp that will sufficiently melt the solder and allow it to flow. (250 to 300oF seems to ring a bell, but don't trust me on that). If the solder isn't sufficiently hot, it won't stick!!!