Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 5/3/83; site utcsrgv.UUCP Path: utzoo!utcsrgv!spoo From: spoo@utcsrgv.UUCP (Suk Lee) Newsgroups: net.audio Subject: Re: linear tracking query Message-ID: <3255@utcsrgv.UUCP> Date: Thu, 9-Feb-84 17:49:48 EST Article-I.D.: utcsrgv.3255 Posted: Thu Feb 9 17:49:48 1984 Date-Received: Fri, 10-Feb-84 03:50:36 EST References: <397@sii.UUCP> Organization: CSRG, University of Toronto Lines: 37 I would suspect that the variable pitch "feature" was thrown away for two reasons: I don't think that many people actually use it, and it was a "bug" turned into a "feature" that turned back into a "bug" when quartz locked oscillators became common in DD turntables. In the beginning... direct drive turntables used an internal oscillator to lock the drive speed (not necessary with the synchronous motors typically used in belt-drive turntables). However, these oscillators drift with temperature, which prevented the manufacturers from factory-setting the speed. So, they slapped a cheap strobe on the platter, stuck in a pot in the oscillator circuit, and hey presto, we now have a "feature". With the advent of quartz locked oscillators, it became difficult to offer a quartz-locked variable speed feature (most DD's with quartz-lock turn it off when you turn on the variable spead "feature"-- Technics being an exception), and I suspect that manufacturers threw this "feature" away since they don't need it anymore. -- From the pooped paws of: Suk Lee ..!{decvax,linus,allegra,ihnp4}!utcsrgv!spoo