Atari Mega ST 4 disk or boot problem

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Atari Mega ST 4 disk or boot problem

Postby tjlazer » Sun Feb 25, 2018 7:25 pm

My Mega ST started having a problem loading disks. When you insert a disk, it reboots constantly from between every 2 to 10 seconds as it tries to boot the disk. Sometimes it gets half way then reboots and loads the disk again, other times it chokes and will load for a second and reboot. Does this in a loop. I found that if I have an external drive connected, and when I can finally get to a TOS desktop, I can load programs fine on the external. But when I try on internal, it does as said above. I think it might be a power supply problem or caps, or the drive. I did notice a large cap 4700uf 16v next to the power supply and floppy. Once I tried to move it and it rebooted. Then system seems to be ok for a while loading disks fine! Then later on back to the same problems. Trying to narrow down the problem. I can try to swap the drive and power supply from anther ST to check.

Anyone seen anything like this happen or have any idea what's going on?
Last edited by tjlazer on Sun Feb 25, 2018 10:05 pm, edited 1 time in total.
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Atari Super Hero
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Re: Atari Mega ST 4 disk or boot problem

Postby Atari030 » Sun Feb 25, 2018 8:27 pm

Megas use a higher rated PSU than an ST, external PSU's use their own supply, unless you run it off the keyboard. So my bet would be PSU. The 4700 cap is easily replaced and worth doing too.

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