The Sinclair QL Forum

Shall I check these before trying to check the socketed ICs on the good QL? I don't know an easy way to test the 74s, so I'll probably leave it for later. On the 74LS257 (IC19/20): pin 15 is /OE and pin 1 is SELB so you can check for presence or absence of the high impedance state from A0/B0 to Q0,...

But it would run, at least, wouldn't it? That would let me know the video generator and processor are OK, at least. The 8301 can generate a video image without a CPU. It would just be black because the CPU can't put any data in the RAM, but it would be a valid video signal. I've just started readin...

Does the memory checking work with no memory installed? In case a full chip is bad, at the lower portion of the memory, no RAM would be available. It would try and fail immediately. So, here's a brief outline. The 68008 is the CPU. The 8301 is the Master Chip. It does video generation from main RAM...

Hi Dave, I did a quick search on EP1810LC-25T, the cheapest I can find is $18 plus shipping. I have a EP1810 programming adapter for my ALL03A programmer, so the PLDs can be programmed easily. When I find time, I will if I can decompile tge Altera JED files. I can get them for $13 shipped, new old ...

Hi there! Welcome to the forum! Traditionally, white screen suggests faulty memory. It could also mean a bad 8301. Luckily, all of those are fairly easy to get your hands on. The first thing you need to do is to get a copy of Minerva. This is a replacement OS for the QL that does more advanced memor...

It's the same membrane. I haven't heard of Sintech before. Good to know there's a second source.

Yes, you can use both together. There are no conflicts.

There aren't currently any new QL-SD for sale, but there will be in a few weeks. The QL-SD 2 is prototyping now...

The new membranes sold by RWAP are of infinitely superior quality and durability. They will not expire during your lifetime.

Highly recommended.

The equations of INGOT20 are available. That's version 20.24 dated 15 Feb 94. The catch (as I have just been discussing with Nasta) is that they're extremely limited in usefulness. The device as a type doesn't really exist any more so the knowledge doesn't transfer easily to any other device. The av...

You tell me what you plan to use your QL for, and I'll give you some pros and cons that relate to your situation. :D Dear Dave, I bought the QL because 34 years ago when it came out, I had a Spectrum (which I still use) and I could not afford a PC so expensive. I have always read so much about the ...