Unidisk and drive repairs. Info needed please.

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Tracer bullet's picture
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I mentioned earlier that I purchases a pair of 5.25" unidiscs and a 3.5" drive. Is there a way to test and align these drives? I have no OS discs for the 2gs system and will have to bootstrap the system to create system discs I guess. I'll probably have to clean align the drives eventually. Can anyone recommend a site where I can find this info from? How hard is it to do? Any special tools required? I read along time ago about syncing the 5.25 drive with a 60 hz florescent bulb. Again, I have NO software for the system and will have to start from scratch using ADTPro. I ordered a cable online so I can make the discs I needed. I'll need some help on this as well I guess.
Thanks.

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Doug

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Re: Unidisk and drive repairs. Info needed please.

Tracer,

Please see your "Removing yellowing off of plastics" post.

Steven Smile

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Re: Unidisk and drive repairs. Info needed please.

Tracer bullet wrote:

I mentioned earlier that I purchases a pair of 5.25" unidiscs and a 3.5" drive. Is there a way to test and align these drives? I have no OS discs for the 2gs system and will have to bootstrap the system to create system discs I guess. I'll probably have to clean align the drives eventually. Can anyone recommend a site where I can find this info from? How hard is it to do? Any special tools required? I read along time ago about syncing the 5.25 drive with a 60 hz florescent bulb. Again, I have NO software for the system and will have to start from scratch using ADTPro. I ordered a cable online so I can make the discs I needed. I'll need some help on this as well I guess.
Thanks.

If the Drives are out of Speed Adjustment, you can usually format a blank Disk, and use it... If you drive is very far out of spec, you will want to Re-Format that Disk, ( after backing up your Data ), because it might not work anymore on your in-spec Drive, or anyone else's in-spec drive..

I prefer Central Point Software's Copy ][+, using the Verify-->Disk Speed. You will need Two Disks ( not including the Disk for ADTpro )

Copy ][+ 5.5 is the Last DOS 3.3 version, Copy ][+ 9.1 is about the last ProDOS one. The .DSK files are for 5.25", the .PO files are ProDOS, usually 3.5". The ProDOS versions of Copy ][+ will CATALOG and Test DOS 3.3 disks. All should have the Disk Speed Verify. Use a BLANK or SCRATCH disk for the Speed Verify, it will Erase the highest Track, IIRC..

I have adjusted my Disk IIs many times, I have never needed to adjust the the 5.25" or the Duo Disk, yet...

The 60Hz/50Hz test requires dissembling the Drive, so you can see the Fly Wheel on the Bottom...

Are you trying the Audio Route, or RS-232.. I recommend Serial.. I get 115,200bps transfers...

MarkO

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Re: Unidisk and drive repairs. Info needed please.

I can't tell you how exactly how to do the 5.25 drives, but there is a video that will explain how to maintain the 3.5 and the 5.25 drives:

http://vimeo.com/14581224

And about what MarkO said:

Read the Computist magazine. To copy disks on 5.25 drives, drive 2 must be set at a slightly lower speed than drive 1.

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Re: Unidisk and drive repairs. Info needed please.

insanitor wrote:

I can't tell you how exactly how to do the 5.25 drives, but there is a video that will explain how to maintain the 3.5 and the 5.25 drives:

Oh!!!! Remove the Cover from the Disk II, the Analog Board for controlling the Spindle Speed, is mounted Verticaly across the Back of the Drive.. One the One side, ( Right side, IIRC ), there is a Multi-Turn Potentiometer, use a Jeweler's Screwdriver to turn, while observing the Copy ][+ Disk Speed test, you will see the Speed change in Real Time... According to Copy ][+, it should be 200.0 ms, with a Min of 198.0 ms, and a Max of 202.0 ms..

Nice Video!! I see it was posted by Ken Gagne, he is a guest on Retro Computing Roundtable, this month..

Quote:

And about what MarkO said:

Read the Computist magazine. To copy disks on 5.25 drives, drive 2 must be set at a slightly lower speed than drive 1.

Many games required a Slower Target Drive Speed when Copying.. You could set D1 closer to 202.0 ms, and D2 closer to 198.0 ms and still be in spec...

MarkO

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Re: Unidisk and drive repairs. Info needed please.

MarkO wrote:

Many games required a Slower Target Drive Speed when Copying.. You could set D1 closer to 202.0 ms, and D2 closer to 198.0 ms and still be in spec...

At the risk of asking a dumb question, why?

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Re: Unidisk and drive repairs. Info needed please.

I wondered the same thing. EDD 4 Plus tells you to set the drive speed of drive II several ticks below drive 1. (I think it was 296 vs. 299/300rpm)
Zan