Path: utzoo!utgpu!water!watmath!clyde!rutgers!ames!pasteur!ucbvax!decvax!decwrl!sun!pitstop!sundc!seismo!uunet!portal!cup.portal.com!thad
From: thad@cup.portal.com
Newsgroups: comp.sys.amiga
Subject: Re: Homebrew external 3.5" drives
Message-ID: <3252@cup.portal.com>
Date: 15 Feb 88 23:41:38 GMT
References: <4999@pyr.gatech.EDU>
Distribution: na
Organization: The Portal System (TM)
Lines: 37
XPortal-User-Id: 1.1001.2826

Eric and I jointly did that article re: adding 3.5" drives to one's Amiga
(I did the schematics, proof-read the article, and hand-built (wire wrap)
one unit to be suuuuure it worked! :-)  Usually accompanying that article
(in ARCs on BBS systems) is another article I wrote (with accompanying
schematics and IFF photos) re: modifying A1010 drives for use with external
power.

I haven't seen Eric in over a year; he hasn't attended FAUG or BADGE meetings
and he may have moved out of the area.

Since that original article, I have updated the schematics to diagram the
differences required to connect 5-1/4" drives.  And I've built a LOT of those
circuits, even some for church groups who use the Amiga to produce their
flyers and needed both 3.5" and 5.25" floppies for a variety of reasons.

Halted is still in Sunnyvale, but that (original) drive is no longer in stock.
Newer Toshiba drives (physically smaller) operate just fine, as do nearly
ANY other "modern" 3.5" floppy.  Caution must be observed with drives such
as Matsushita, however, since there appears to be a "problem" with the
track zero handling with these ... it's possible to "attempt" to step the
heads out beyond track zero (e.g. to track -1) ... this was noted by people
who've installed the noKLICKstart patches to their Kickstart disks.  I do
have a circuit fix to correct that problem (adapted from the information
handed out at the 2nd Developers' Conference in Monterey).

If there's interest, I can post an updated article to the binaries newsgroup
(because of the IFF material).  Send me e-mail (address below); also include
instructions for posting to the binary newsgroup (e.g. do I post directly,
or to the moderator?).  The updated article would also be available on the
BBS and commercial services in the SF Bay Area.  It'll be approx. 10 days
since I'm going to be out of town most of this week.

Thad Floryan

...!sun!portal!cup.portal.com!thad      (or ...!well!thad)
BBS-JC 415/961-7250 (300,1200,2400) 24hrs
FAUG-BBS 415/595-2479 (300,1200) 24 hrs