Path: utzoo!attcan!uunet!crdgw1!crdos1!davidsen
From: davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr)
Newsgroups: comp.unix.xenix
Subject: Re: ST-251 Drives as RLL?
Message-ID: <1952@crdos1.crd.ge.COM>
Date: 21 Dec 89 19:58:19 GMT
References: <117@mnopltd.UUCP> <1989Dec15.165414.3335@ddsw1.MCS.COM> <1933@crdos1.crd.ge.COM> <129@avatar.UUCP>
Organization: GE Corp R&D Center, Schenectady NY
Lines: 19
Reply-exos:@crdgw1:To: davidsen@crdos1.crd.ge.com (bill davidsen)

In article <129@avatar.UUCP> kory@.UUCP (Kory Hamzeh) writes:

| Thats not true. I had several different kinds of MFM drives sold to me
| as RLL. They would all work fine for about a couple of months, then they
| would develope a couple of new bad sectors a day. Just because the drive
| works for a day or two, it doesn't mean that there will be long term
| reliability.

  I've seen that. A good power line filter usually cures the problem. It
may also be that the controller in this case is marginal. There are some
good articles on how RLL works and what can go wrong. I won't try to
restate the technical stuff, but there is no reason to expect gradual
deterioration other than line noise of a combination of controller and
disk which is marginal (and every vendor makes a few bad ones, no question).
-- 
bill davidsen	(davidsen@crdos1.crd.GE.COM -or- uunet!crdgw1!crdos1!davidsen)
"The world is filled with fools. They blindly follow their so-called
'reason' in the face of the church and common sense. Any fool can see
that the world is flat!" - anon