gt4785b@pyr.gatech.EDU (CARTER) (02/14/88)
I've just recently read a copy of an article (being passed around on floppy) titled "Adding a Third and Fourth Floppy Disk" by Eric D. Black, dated April 1986. It describes building the small amount of circuitry needed for adding external 3.5" drives to the amiga. I have a few questions: 1) Eric, are you still out there usenet somewhere? If so, please send me your email address. 2) Eric used Toshiba drives (model FDD-4403AQK-02), from Halted Specialties in Sunnyvale, for $99. Can somebody send me Halted's address and phone. Do you know whether they still carry the drives? OR are there any other places selling these drives? 3) Are there other drives that are plug-compatible? (and don't say NEC model FD1035; the Toshiba was much quieter, and I rather like that feature). 4) If I were to lay out a PC board for this circuit, would anyone else be interested in having one? It has about 3 TTL chips and a few transistors and resistors; nothing major. The main advantage of a PC board is that it will free you from hand-wiring the DB-23 and 34-pin drive connectors. I will summarize and post the results. David Carter gt4785b@pyr.gatech.edu
thad@cup.portal.com (02/16/88)
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
hansb@ariel.unm.edu.unm.edu (Hans Bechtel) (02/17/88)
I am interested in those binaries for the 5 1/4 drive... I have a 5 1/4 tandon dirve that I am STILL trying to make work.. It does kinda work in transformer (ibm emulation) mode, but it does not work in the amiga mode... The amiga mode does not recognize the "df2:" not even being there, even after being mounted. Hans Bechtel
clark@ssc-vax.UUCP (Roger Clark Swann) (02/20/88)
**** line eater food **** I too am in the process of rigging up an external 3.5 floppy drive for the Amiga. The required interface circuit is nothing difficult to put together. However, it would be nice to have a small pc board to put the parts onto or even pre-built card, ready to install. Does anyone know if such an item is made / offered by some co. ??? It seems like there should be sufficient demand for this type of thing to be produced in quantity... If no one else is doing this, maybe I should start.... Comments??? Roger Swann uucp: uw-beaver!ssc-vax!clark