Problems with/after ROM replacement, vDrive and Exapanderam

[Ruptor]

Question: Could anybody suggest an expert to take a look at my computer who is close to my neck of the woods on the continent (Slovenia)?

What about a TV of HiFi repair shop? If you dig up the information for an issue 5 upgrade and give them just the PCB out of the box anyone with a soldering iron that can solder electronics can do it for you. Just a thought if you raise the mains voltage input to the PSU with a step up transformer (variac maybe) to recover the 5 or 10 volts lost the Microdrives & everything might start working again.

[Pr0f]

Just a thought - but European Mains voltage is a little lower than UK voltage - we regularly get 240V on our mains - I think it's somewhere between 220 and 230 in most European countries - it's not much of a percentage - but if your PSU is just on the edge... It's just one more place to look

[Ruptor]

Just a thought - but European Mains voltage is a little lower than UK voltage - we regularly get 240V on our mains - I think it's somewhere between 220 and 230 in most European countries - it's not much of a percentage - but if your PSU is just on the edge... It's just one more place to look

An echo of my last two posts.

[martyn_hill]

Hi Andy!

Question: Could anybody suggest an expert to take a look at my computer who is close to my neck of the woods on the continent (Slovenia)?

I wouldn't claim to be an 'expert', but I will be in and around Trieste in N Italy over the next few weeks visiting family - if you think I could help, feel free to PM me (martyn_hill)

M.

[AndyZX]

Hi Andy!

Question: Could anybody suggest an expert to take a look at my computer who is close to my neck of the woods on the continent (Slovenia)?

I wouldn't claim to be an 'expert', but I will be in and around Trieste in N Italy over the next few weeks visiting family - if you think I could help, feel free to PM me (martyn_hill)

M.

Hi Martyn, thank you very much, I appreciate it. I posted my call on the Slovenian FB retro computers page and one colleague will take a look at it. I trust he will be able to solve the problem, but if not I will get in touch. Thanks again!

[AndyZX]

Question: Could anybody suggest an expert to take a look at my computer who is close to my neck of the woods on the continent (Slovenia)?

What about a TV of HiFi repair shop? If you dig up the information for an issue 5 upgrade and give them just the PCB out of the box anyone with a soldering iron that can solder electronics can do it for you. Just a thought if you raise the mains voltage input to the PSU with a step up transformer (variac maybe) to recover the 5 or 10 volts lost the Microdrives & everything might start working again.

Thanks, I found help through the Slovenian FB retro computers page and I trust we will able to solve the problem. In any case expert guidance from the QL forum is invaluable so thanks again to everybody!

[AndyZX]

Question: Could anybody suggest an expert to take a look at my computer who is close to my neck of the woods on the continent (Slovenia)?

What about a TV of HiFi repair shop? If you dig up the information for an issue 5 upgrade and give them just the PCB out of the box anyone with a soldering iron that can solder electronics can do it for you. Just a thought if you raise the mains voltage input to the PSU with a step up transformer (variac maybe) to recover the 5 or 10 volts lost the Microdrives & everything might start working again.

Thanks, I found help through the Slovenian FB retro computers page and I trust we will able to solve the problem. In any case expert guidance from the QL forum is invaluable so thanks again to everybody!

[AndyZX]

Hello everybody,

after some time I am back with more info and some additional help for troubleshooting.

As many suggeseted I got in touch with a colleague who undertook the necessary mods to the Issue 5 board and he did a great job.

But surprise, surprise - things are still not 100% OK.

With Minerva ROM my QL wouldn't load from the vDrive nor from the MDVs. I reverted back to the AH ROM and things improved 50%. Suddenly, my vDrive was fully operational, whereas MDVs would still not load programmes.

I have to mention that removing Minerva I broke the pin on the upper right side. (I know, I should have used the ROM extractor but don't have one yet.) Anyhow, I think the pin was OK before so I would rule that defect out.

The situation with AH ROM installed is now the following:
- I can load nearly all files from the vDrive (there are some excepions like Spook but I had a problem with it before);
- MDVs seem to roll ok - there is no problem loading shorter SBASIC files;
- I can even load Metacomco Pascal, in connection with its own ROM;
- but I have problems with most MDV programmes: they might load the intro screen (HyperDrive or 3D Slime), or a part of the programme in SBASIC (QL-Decision Maker), however the loading process would end with a long beep, reset, infinite loading loop or mostly with a message "out of memory" (I attach some typical screenshots);
- it seems there is a problem with memory - out of memory message is usually linked to RESPR or ALCHP functions;
- there does not seem to be a RAM problem - Minerva showed the standard 128K setting was ok and, in any case, (same) programmes do function well if I load them from the vDrive.

I guess many are wondering why do I bother with MDVs while I have the vDrive functioning (with AH ROM). True, but I have some programmes on cartridges and would still like to use the original QL funcionality.

Any ideas of what is going on would be greatly appreciated. Thanks!

[Derek_Stewart]

Hi,

The problem maybd related to the broken pin on the Minerva.

But Minerva should improve the Microdrive access, as AH rom is full of bugs.

Do you have the 2 resistors on top of the 8302? This improves the microdrive reliabiliy.

[AndyZX]

Thanks Derek, will fix Minerva and put the resistors on the top of 8302 - hope that will solve the problems.