ql white screen

[thecaver99]

having done a lot of reading about the ql as this is my first.
i do belive that the white screen is a sign of bad ram, i have tried the piggy back with no result, im just waiting for sockets to arrive and then will socket the ram and then be able to test each ic in another machine.

would the white screen be a symptom of bad ram?

[XorA]

yes

[dilwyn]

In case it helps, there's an online QL service manual on Urs's site, at:
https://www.sinclairql.net/srv/index.html

[jobdone]

just to widen your thought pattern, although it is a normally a RAM fault, it may/may not be the ram itself... Quite a few people install a minerva board at this point to show on the screen the stuck bits (indicating which IC). After resetting a few times, this should still show the same IC, if not it could be multiples or the 74 series logic to the left of the ROMs. a faulty zx8301 can also cause a white screen or green screen as this also has to do with the RAM. Broken traces may also do this.

[tofro]

My personal statistics: In 50% of the cases it's the multiplexers and/or bus drivers (the 74xxx chips). 40% is an actual RAM fault, 10% something else.

[thecaver99]

It turned out to be 5 dead ram chips, 1 in lower ram and 4 in upper ram.
All replaced and now the ql lives once more.

[Popopo]

It turned out to be 5 dead ram chips, 1 in lower ram and 4 in upper ram.
All replaced and now the ql lives once more.

Congrats!

[thecaver99]

It turned out to be 5 dead ram chips, 1 in lower ram and 4 in upper ram.
All replaced and now the ql lives once more.

Congrats!

Cheers,

just the new memrain and bubble mat then have a fully working system.
this is my fist QL ive ever used, a mate had one back in the 80s but i never knew anything about them i was just a speccy user.
the person ive got it from is also sending me a Miracle Systems Expanderam 512k memory card and a Micro P QLFDC v5.1 floppy interface for it plus a load of microdrives.
i also picked up an rgbtohdmi and the QL looks really crisp through it on my acer 24 inch monitor.
Just need a way to get some software on the the system now so i can have a look at how the system is.

[jobdone]

congrats. another QL lives on

[jobdone]

Quote "Just need a way to get some software on the the system now so i can have a look at how the system is.". Personally the microdrives are more hassle than their worth, don't attempt to use them without refelting. I would suggest putting that floppy interface to work with a gotek attached. This allows using an emulator and transferring data that way. I can highly recommend sQLux for this and qem-unzip. Dilwyn's site has plenty of software (mainly in zip format), unzip this with qem-unzip to one of sQLux's MDV folders then copy from there to a blank FLP image.