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

      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):
     Number of surfaces                        1
     Number of Memory Blocks
         Total number of tracks               40
         Total number of hard sectors    80
 PDD2 (26-3814):
     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.
 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  
 Jump to page 6
 http://www.classiccmp.org/ cini/pdf/Tandy/Portable% 20Disk%20Drive%202% 
 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> 
 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


Reply via email to