I have 2 Teac FD-235HF disk drives.  I know that they can be used on an Amiga computer.  On the rear of the drive there is a jumper for DF0 and DF1, but where is the RY and DC jumpers or pads located?     :-o

Those are HD drives, so you better bypass the HD switch just in case you decide to stick in a HD floppy that hasn't been taped over.

If they're fairly recent, you probably won't find the mode select switches on the drive's controller PCB, so you'll have to go and get another floppy cable and swap the signals by changing wire positions.

Instructions should be on Aminet, but I don't remember what file. I'd have to search for them too, so I'll leave that to you.

PS. experience has shown me, that writing DD disks in "PC" HD drives will ruin them after a while.. The same doesn't happen with those Chinon half-speed-hd mechanisms that Amigas were shipped with.

Alignment differences and the fact that a HD drive writes with a different magnetizing force will do it. (the HD detect switch doesn't seem to help)

Don't believe me? I've transferred stuff with DD disks vice versa from amiga to PC and it's happened so many times over the years, that I've lost count.

Latest being yesterday: I wrote different disk images to DD disks using a Catweasel and a HD drive. In the end the DD disks started showing errors when I read them on the Amiga. The Catweasel still reads them fine without error.

Now I'm using taped HD disks and writing to them only with the Catweasel and HD drive, no problems so far.

@ DoomMaster,

Off topic, that avatar needs a cigar - the effect will be total :-)

@DoomMaster,

I see. And how often do you wear a camoflaged combat hat in your every day activites? :-)

Sorry, haven't a clue about the drives so I'll shut up now :-)

Doommaster,

What can I say? I'll address the points of your one paragraph block of a post in separate paragraphs:

There IS indeed such a thing as a DD or HD drive: DD drives only work in DD mode, HD drives can work in either mode. The newer drives are HD drives, what is your problem with that? Even though they have two operating modes, they're still referred to as HD mechanisms!

The stepper motor will step just as fast and the spindle motor will spin just as fast regardless of DD and HD mode. The exception to this rule are the famous Amiga "Half-speed HD" mechanisms, that halve the SPINDLE speed when you insert a HD disk. The stepper speed is still the same. (the delay between steps of course depends on the computer sending the commands, but a professional like you knows all about that, eh?)

Just to be completely sure: only Chinon and Sony have ever made these rare, sought after half speed HD drives. Your Teac will not change any of it's motor speeds no matter what disk you feed it. Your Teac will not work as a HD drive in your Amiga without a separate controller board.

I never said the drive would be hurt, please read my post again.

Did you read what I said? My experience with HD drives and DD diskettes == slowly developing read errors. It seems that most HD drives can't adjust their parameters correctly for DD disks and also the HD r/w head is different, which contributes to this problem as well.

You're fine if you only use that single drive to read and write the disks, but if you have to transfer data to a machine with a DD drive (like most Amigas have), you most probably will be experiencing trouble. Nothing a format won't cure - the disks aren't damaged physically - but you will get corrupt data on either end.

Most drives will be better than those Chinon clunkers, but that wasn't really the point.. Like I said before, I've experienced trouble using REAL DD DISKS IN MODERN HD DRIVES.

And about your problem: have you actually unscrewed your Teac drive's controller PCB and taken a look at it? Usually the text is silkscreened onto the PCB or written using the protective laquer even if the actual jumpers / switches are missing.

If you can't see text on the PCB, you'll have to switch the wires around in the floppy cable. (also you can try emailing teac for the schematics of the drive.. good luck with that :-P)

Also, have you just tried plugging the thing in? You might get it to work without any hassle.. Remember, you don't get HD mode without a Catweasel.

Let's get back on topic, people.  Do any of you know where I can find the information on converting a Teac FD-235HF disk drive to an Amiga DD disk drive.  Please let me know.  Thanks.     :-P

@ DoomMaster:
Never used that exact model of Teac drive, but I have had problems making some Teac drives work in the past.
I have had good successes with the earlier Panasonic JU-256 and some Sony drives if that's any help.

Some drives will work if you simply swap the ready and diskchange lines in the 34 way ribbon cable.  I think that's pin 2 and 34 from memory?

There's a bit more info on my technical website if you're interested:
http://amiga.serveftp.net

Look under the floppy drive conversion section.

Doommaster,

This will be my last reply to you ever, on any subject. Wonder why I didn't realise this before.

Why do you reply to only one point I made in my post? It had multiple things I wanted you to know, including a question that would have helped me diagnose your problem more, but you just picked one item (the one you understood?) and went with only that, dismissing the rest.

Anyway, here's a few replies to your "totally correct points that can't be disputed" (oh, they can, you're not the only person in this world who has worked with computers).

I just outlined that you might get into trouble if you try to read those DD disks on other drives than the HD mechanism you plan into installing into your Amiga.

This will not change. Maybe you will get lucky and you won't experience it. Maybe you won't think more of it but consider your disks "dodgy, not worthy of your professional computer", and try another and this disk will work -> problem solved (even though it is still there).

No matter what you say, I have STILL had those DD-HD problems in the past. What I didn't say was, that many of my friends have encountered the same anomalities with DD disks written in both a DD drive and a HD drive in turn. It's a very real problem, but you choose to insist that I'm wrong. Thanks for respecting my life experiences, pal!

Back in 1990 you probably had DD Teac drives, but you probably know best what you had (or do you, I'm beginning to doubt that).. I've had only good experiences using various DD mechanisms with Amigas. They're mostly just plug'n'play.

I've never had the plastic break in Chinon mechs myself.. Just the electronics burn and the wp sensor and disk insert sensor switches go bad. The actual mechanism has always been intact in the broken ones I've encountered.. Of course your drives might have been handled differently. A hint: insert disks shutter first with the metal grabbing disc on the rear side. :-P

You also didn't notice in my posts where I tried to help you (the part where I asked you a question)? Did I write too much and you got bored half way?

Please don't wonder why the people who are trying to help you mysteriously disappear after a few conversations with you! You don't want to be helped! It seems that even when you can't figure it out for yourself, you must tell us how much you know and be better than your helpers.. Learn a little humbleness, please! If you're the one who's needing help, please don't act like you know everything that relates to the subject but is not about it?!

I'm very impressed that you know the difference between DD and HD drives, but this doesn't tell me what's silkscreened onto your Professional Teac's PCB..

Now please tell the next person who volunteers their time and energy to you, whether you see any silkscreened or laquered text that might describe jumpers or switches that could be soldered there. That will actually carry this conversation on. If you see the text, then you already know where the jumpers are. If you don't see any text, please please tell us so someone else can help you more.

You seemed to forget the actual relevance in this thread the instant someone (me) posted something that wasn't 100% about your problem! I did discuss your problem on both posts, how come you totally missed it?

I have to give it to you, you're an excellent troll. Here I am with smoke coming out of my ears and you're probably just laughing how you ticked me off. Harumph.

Now: please only reply to the question I made a couple of times in this thread. Forget all about using DD disks in HD drives. FORGET. It is not relevant and I'm sorry I distracted your line of thought with something like that. Now focus again on how to get your Teac High Density Floppy Disk Drive Mechanism fitted into your Amiga 2000 HardDrive Professional computing machine. (hope that didn't distract you either, I'm having a hard time holding my sarcasm and general assholeness inside me).

Have a good rest of your life, hope someone else has more nerves than me..