Does a PDF exists of "Tandy Disk Drive ll Service Manual"?????
I have the one for the TPDD1 but not the 2.
 

    On Tuesday, August 8, 2017 7:53 AM, John Gardner <gof...@gmail.com> wrote:
 

 So flipping a  3.5"  floppy <would> work,  if the housing for the disk

would let you do that.  Hmm...

And the reason HD disks are unreliable is that the signal returned

by the media when reading the disk is (presumably) too high?

Interesting...

 ...


On 8/8/17, biggran...@tds.net <biggran...@tds.net> wrote:
> The specifications in the PDF for the PDD1 and PDD2 says the following:
> PDD1 (26-3808):
> Disk
>      Number of surfaces                        1
>      Number of Memory Blocks
>          Total number of tracks              40
>          Total number of hard sectors    80
>
>
> PDD2 (26-3814):
> Disk
>      Number of surfaces                        1
>      Number of Memory Blocks
>          Total number of tracks              80
>          Total number of hard sectors    160
>
>
>
>
>
>
> On 8/8/2017 12:39 AM, Gary Weber wrote:
>> > Double-sided doesn't hurt anything of course, although it's too bad you
>> > can't make
>> 3.5" flippy disks as easily as you could 5.25"!
>>
>> After rereading this I wanted to make one critical point.  Remember,
>> if yours is truly the TPDD2, it already is double sided.  It formats
>> the drive as 100K per side (200K total).  You use the "Bank" feature
>> in TS-DOS to switch between which side you're accessing.  So, no need
>> to be fantasizing about flippy-floppies.  ;-)
>>
>> It was the original TPDD that is only 100K single sided.
>>
>> Gary
>>
>>
>> On Mon, Aug 7, 2017 at 8:04 PM, Kurt McCullum <kurt.mccul...@att.net
>> <mailto:kurt.mccul...@att.net>> wrote:
>>
>>    Thanks Brian & Garry,
>>
>>    I suspected that to be the case but when my HD disk appeared to
>>    work I thought I would ask.
>>
>>    Kurt
>>
>>    *From:*M100 [mailto:m100-boun...@lists.bitchin100.com
>>    <mailto:m100-boun...@lists.bitchin100.com>] *On Behalf Of *Brian
>> White
>>    *Sent:* Monday, August 07, 2017 4:41 PM
>>    *To:* m...@bitchin100.com <mailto:m...@bitchin100.com>
>>    *Subject:* Re: [M100] 3.5" Media
>>
>>    I wasn't using these when they were current, but... No question
>>    double density. Aside from the dates when these things were sold,
>>    or the fact that the actual formatting is far less than double
>>    density, or the fact that the original utility disk that came with
>>    it is double density, which are each solid points on their own...
>>
>>    The manual for PDD-2 says to use cat 26-415 or 26-416,
>>
>>    and those catalog numbers are not only double density but actually
>>    single sided.
>>
>>    Double-sided doesn't hurt anything of course, although it's too
>>    bad you can't make 3.5" flippy disks as easily as you could 5.25"!
>>
>>    But trying to use SD/DD read/write head signal strength on HD
>>    media is going to either not work at all, or work very
>>    poorly/unreliably, or worse, *appear to work but be corrupt*.
>>    Because the HD media is more sensitive than the older media, and
>>    operates at lower signal strengths than the older media. An SD or
>>    DD drive write signal is stronger to match the weaker media it was
>>    meant for. So in effect you are over-driving the newer media. In
>>    plain audio you can tell when that's happening because you
>>    actually hear the distortion like a ripped speaker. As data, you
>>    can't hear it directly or tell it's happening, which makes it more
>>    dangerous. They should have made HD disks so they don't even fit
>>    in older drives. Make them slightly longer maybe, so that old
>>    disks could still fit in new drive, but new disks couldn't fit in
>>    old drives. The guy who sent me my copy of the utility disk sent
>>    one of each type, and the HD copy actually works, which is what I
>>    mean by "dangerous", because, going by that, you would conclude
>>    "It works, so, it works."
>>
>>    Jump to page 6
>>
>> http://www.classiccmp.org/cini/pdf/Tandy/Portable%20Disk%20Drive%202%20Operation%20Manual.pdf
>>
>> <http://www.classiccmp.org/cini/pdf/Tandy/Portable%20Disk%20Drive%202%20Operation%20Manual.pdf>
>>
>>    Jump to page 41
>>
>> http://www.colorcomputerarchive.com/coco/Documents/Radio%20Shack%20Catalogs/Tandy%20Computer%20Catalog%20and%20Software%20Reference%20Guide%20(1988)(Tandy).pdf
>>
>> <http://www.colorcomputerarchive.com/coco/Documents/Radio%20Shack%20Catalogs/Tandy%20Computer%20Catalog%20and%20Software%20Reference%20Guide%20%281988%29%28Tandy%29.pdf>
>>
>>    That catalog doesn't say DD explicitly, but it does say others are
>>    HD and 1.44M explicitly, which makes everything else not-HD by
>>    omission.
>>
>>    I assume that somewhere a more authoritative reference on the
>>    catalog numbers would show that more explicitly.
>>
>>    --
>>
>>    bkw
>>
>>    On Mon, Aug 7, 2017 at 6:41 PM, Gary Weber <g...@web8201.com
>>    <mailto:g...@web8201.com>> wrote:
>>
>>        Double Density for sure.  A long time ago, I had attempted to
>>        format a
>>        high density disk on a TPDD2 but it gave an error.  I've
>>        always had
>>        to use double density disks.
>>
>>
>>        On Mon, Aug 7, 2017 at 2:33 PM, Kurt McCullum
>>        <kurt.mccul...@att.net <mailto:kurt.mccul...@att.net>> wrote:
>>        > For those who have used a TPDD2 in the past, I have a
>>        question about media
>>        > type. Do these drives prefer double density (720k) or high
>>        density (1.44mb)
>>        > media? I've tested with both from by using recycled media
>>        from years gone by
>>        > and both seem to work. My primary interest in the drive is
>>        to see if I can
>>        > improve mComm but as I'm testing, I'd like to actually use
>>        the proper media.
>>        >
>>        > Kurt
>>        >
>>
>>
>>        --
>>        Gary Weber
>>        g...@web8201.com <mailto:g...@web8201.com>
>>
>>
>
>


   

Reply via email to