From owner-freebsd-hardware Mon Dec 30 06:42:09 1996 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.4/8.8.4) id GAA28368 for hardware-outgoing; Mon, 30 Dec 1996 06:42:09 -0800 (PST) Received: from diablo.ppp.de (diablo.ppp.de [193.141.101.34]) by freefall.freebsd.org (8.8.4/8.8.4) with SMTP id GAA28353 for ; Mon, 30 Dec 1996 06:42:04 -0800 (PST) Received: from freebie.lemis.de by diablo.ppp.de with smtp (Smail3.1.28.1 #1) id m0veiuU-000QXsC; Mon, 30 Dec 96 15:41 MET Received: (grog@localhost) by freebie.lemis.de (8.8.4/8.6.12) id OAA02928; Mon, 30 Dec 1996 14:48:48 +0100 (MET) From: grog@lemis.de Message-Id: <199612301348.OAA02928@freebie.lemis.de> Subject: Re: DAT reliability In-Reply-To: <3.0.32.19961230125151.0068a21c@pop.dial.pipex.com> from Simon Reading at "Dec 30, 96 12:53:06 pm" To: aat81@dial.pipex.com (Simon Reading) Date: Mon, 30 Dec 1996 14:48:48 +0100 (MET) Cc: freebsd-hardware@FreeBSD.org (FreeBSD hardware Users) Organisation: LEMIS, Schellnhausen 2, 36325 Feldatal, Germany Phone: +49-6637-919123 Fax: +49-6637-919122 Reply-to: grog@lemis.de (Greg Lehey) X-Mailer: ELM [version 2.4ME+ PL28 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-hardware@FreeBSD.org X-Loop: FreeBSD.org Precedence: bulk Simon Reading writes: > At 12:59 30/12/96 +1030, Michael Smith wrote: >> Simon Reading stands accused of saying: >> The SDT-7000, as has been observed, has a completely >> different head assembly design. The transport, insofar as any >> helical-scan transport can be, is pretty good. You can whine all you >> like about consumer-grade product, but TBH your average consumer-grade >> transport is pretty bloody good. Sony are going to hurt a lot more >> with 5% returns on a consumer product than on a computer product. > > 1. As you say, the SDT-7000 is a new design. Like ANY new product, I would > expect more teething troubles than one which has been out in the market for > longer. (NB. I'm not saying this was the cause of my problems). I don't think that *any* is valid. Many new products have teething troubles; many others don't. During this discussion I have come to the conclusion that the HP C1533A is a whole lot more reliable than the 35480A, for example. > 3. How many people listen to their DAT player four hours _every day_? How > long would it last if they did? I listen to my CD player for hours every day. It's about 7 years old now. I don't have a DAT player, but I would guess that the typical duty cycle for hi fi equipment could be higher than for tape backup devices. >> I would guess that the 5200 has been >> out for longer and that any bugs/problems would be more likely to be >> observed/sorted out than any with the 7000. The small price difference >> between the two models make me think that there has been little change in >> the funamental mechanism design and that 8000rpm may be too fast to >> transport the tape using the existing mechanism. >> >> The price of the unit has little or nothing to do with its cost, >> design or taste when deep-fried. I've observed over the last few >> years that as a general rule, most DAT units "just work". I've only >> met a few "persistent plaintifs" who seem never to be able to get a >> working unit. > > There are two separate issues here. > 1. Infant mortality. The reason why I returned my SDT-7000 was because it > didn't work. Agreed. But there was evidence in your case that the device had already been installed somewhere and returned for some reason. > The reason why I have not exchanged for another SDT-7000, is in case > it is a problem with the batch. (I can't afford to waste time with > another dud). Fait accompli. You're assuming that you would be better off with another brand. I don't think that these problems extend to whole batches. > 2. Expected Lifetime. As stated before, I'm much more interested in how > long I could expect a DDS-2 to last. From correspondence I've received I'd > guess 18 months+ light usage, six months or so heavy usage (I'm happy to be > corrected on this). I suspect you're (mis)quoting me here. I was talking about the 35480A when I mentioned 6 months. I'm pretty sure I've had the C1533 for well over a year, and it has had well beyond the expected 12% duty cycle in that time. > Does one DDS-2 manufacturer produce more reliable drives than > another? I don't think we're much closer to an answer on this > question. There are bound to be differences in reliability. It's just the question whether they are statistically relevant. My feeling is that the technology has matured considerably in the last 5 years, and that it will continue to mature. As a result, I would prefer a new model over an old model, even if other factors (capacity, speed) remain the same. Greg