From: gene h. <ghe...@wd...> - 2012-02-22 00:41:31
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On Tuesday, February 21, 2012 07:33:44 PM Steve Blackmore did opine: > On Tue, 21 Feb 2012 16:33:00 -0500, you wrote: > >Quick test this afternoon, duty cycle sucks, need MUCH narrower slots. > >Since I don't have anything narrower for bits that will cut that brass, > >I believe I will make another identical brass wheel and mount it > >slightly out of time to narrow the slot, there is room for it in the > >opto's. > > Hi Gene, I used OPB916BZ opto's > > http://www.optekinc.com/datasheets/OPB916.PDF > > slots are 3mm with 3mm space between, all slots 6mm long apart from > index which is 12. Index opto is fitted nearer to wheel. Slots start 2mm > in from edge of wheel. Diameter of wheel was made to suit those params. > I get a super square pulse with even mark/space - checked on the scope > and they are as close to perfect as doesn't matter :) Wheel is not > enclosed and there is no jitter from either daylight or fluorescent tube > above lathe. > > Steve Blackmore Those look to be pretty similar, with yours a bit more versatile since it has the inversion ability. Mine are, according to the spec's, 60ns rise, 15ns fall. Yours may have a slightly deeper slot. Either should do the job. My problem is that I don't have a huge choice in diameters, no room so I have less than 5mm I could shrink, and likely a mm bigger will hold the pcb out far enough the change gear cover wouldn't fit anymore. Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> Every man is as God made him, ay, and often worse. -- Miguel de Cervantes |