exxos's Atari, Amiga & retro forum

Hi all,

I aquired a Mega ST4 a month or so back. It was very unstable so I've used the exxos kit of parts to rebuild the PSU and shows the correct voltages. This has made a massive difference to it, in that it behaves a lot better.

I'm trying to run cubase 3.1, with a Unitor plugged into the cartridge port. I'm finding that it seems to work fine for a while, then it will start give 'internal error' popups. If i then restart cubase it will then complain of 'no key' for cubase.

So something is still amiss hardware wise. I do have some extra bits to fit, like the buffer and the booster, but i dont want to go anywhere near that until i've figured the instability issue.

So, seasoned atariists, where would you look to think about troubleshooting this? Is it possible it's ram related, or is this likely to be some form of power issue on the motherboard itself

Thanks in advance for any encouragement or support!

Rich

Bad connections on cart port ?

I'm assuming Cubase uses cartridge port I don't know anything about it...

Yes it uses the cart port for the Unitor and has the dongle cartridge in a pass through port.

I gave up using a midex because it seemed very sensitive on an FM. The unitor worked on the fm, but did do some of these same sort of things. The only constant between all of those 3 was the cubase dongle. I also tried an STe but the cartridge port on that seemed completely dead.

I'm almost at the giving up and going back to the pc stage, which would really be a shame as I feel so much more creative working on the ST.

I've just found a memtest program so going to give that a go next ?

If it's taking it's time to fail, then it could be thermal, though I still wouldn't rule out bad cartridge port connections. You could have a bad solder joint or other component that fails when it warms up.

Is it possible to run the Mega 4 without the covers and a fan blowing over it, and the same for the Unitor?

Do it one at a time, so that it is obvious which one was the problem.

Hi Mr Jonnie :)

I did wonder if it was thermal. The fact that the midex and unitor behave similarly (the midex worse - but it has more on it?) made my gut instinct say that it's going to be the ST in some way... but I suppose it's all 25-30 years old as a minimum. I'll give that a go.

Hey - sorry for the late update, but this was eventually down to a dicey cubase dongle. It may be redeemable with a conductive pen or something, but for now i'm happy with its ebay sourced replacement.

@richard.faulkner Great that you sorted it out in the end...would be good to hear if you do resurrect that dodgy dongle!

Is it for Cubase 2 or 3?

cubase 3.1/cubase score.

Ah, yes - I'm not aware of any stable versions of Cubase that can be used without the original dongles for v3 & later.

I've got 2 or 3 of the red Cubase dongles (and also one for Falcon Audio IIRC) & from what I remember some of the dongles only work on certain machines while others work fine on any machine.