Well, that confirms what I deduced. Stupid enough, I just assumed i'd be SS/DS.
And I never read the specs... Greetings from the TyRannoSaurus
Jan-80
From: "biggran...@tds.net" <biggran...@tds.net>
To: m...@bitchin100.com
Sent: Tuesday, 8 August 2017, 16:29
Subject: Re: [M100] 3.5" Media
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> 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-bounces@lists. bitchin100.com] On Behalf Of Brian White
Sent: Monday, August 07, 2017 4:41 PM
To: 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
Jump to page 41
http://www. colorcomputerarchive.com/coco/ Documents/Radio%20Shack%
20Catalogs/Tandy%20Computer% 20Catalog%20and%20Software%
20Reference%20Guide%20(1988)( Tandy).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>
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> 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
