On Sunday 23 April 2017 02:03:02 Chris Albertson wrote: > Gene, > They do make such devices. But there is one fundamental difference > between a fiber cable and an isolator, the cable can have any length > and hence a WIDE range if attenuation. The cable could be short and > with high quality termination and low losses in the conniptions of it > could be very long with poorly made terminals > > So the transmitter / receiver has to be able to handle a couple others > of magnitude different attenuation rates. > > Look on page 2 of the below linked document The figures describe > EXACTLY what you are asking for and it even compares it to an isolator > like you did > http://media.digikey..../fiber-optic%20devices%20toslink.pdf > <http://media.digikey.com/pdf/data%20sheets/toshiba%20pdfs/fiber-optic >%20devices%20toslink.pdf> > IP will look when its daylight and I've got a cuppa and one eye open.
Thanks. > DIgikey sells the stuff and its cheap because these parts are used in > consumer electronics and produced by the millions. Precisely what I am looking for. > > On Sat, Apr 22, 2017 at 1:01 PM, Gene Heskett <ghesk...@shentel.net> wrote: > > On Saturday 22 April 2017 14:26:56 Linden wrote: > > > When I worked in the semi con industry we used to have converters > > > for regular rs232 serial com at 9200 bod. Was a 9 pin sub d at one > > > end of the adaptor then 2 glass fiber cables plugged in to the > > > other. The receptacle and the fiber cable were made by omron. I > > > think the device itself was made in Austria and grew out of some > > > ones basement to small production. The only problems we had were > > > the glass fiber portion of the cables not being crossed when some > > > one had it apart or corrosion on the little PCB due to exposer to > > > HF fumes and other nasties. This was on machines designed and > > > built in the early 90. > > > > Gee I wish I could convince folks I do NOT need a serial signal at > > such and such a baud rate. ALL I want to do is turn on an led > > shining into the fiber at one end, and detect it with a high gain > > phototransistor at the other end. Seems pretty simple to me. Turn > > on the led shining into the end of the fiber for 3 u-secs, the > > phototransistor does a turnon at the other end, and voila! a step > > pulse, with no noise being shoved into the circuit on either end. > > Leave another led turned on for the duration of the dir signal when > > I want to reverse the direction. rs-422-485 gismos I have a bag of > > 5, still haven't found a place to put them other than hanging on the > > end of a usb extension cable as a pretty, lights up bright red so I > > can pick my way out of the garage if the overhead lighting breaker > > fails. I was going to use one to drive my vfd, till I found the fake > > vfd didn't didn't have any seriel circuitry, not even designed in > > but un-populated on its boards. A SpinX1 runs it rather nicely > > after I programmed it from its own keypad. > > > > > On April 22, 2017 9:56:27 AM PDT, Gene Heskett > > > <ghesk...@shentel.net> > > > > wrote: > > > >On Friday 21 April 2017 19:10:23 dave wrote: > > > > > > > >Did you get my PM to you yesterday evening? > > > > > > > >> Years ago when I thought fiber might catch-on I grabbed some > > > >> 62.5/120 plenum fiber at Boeing Surplus. > > > >> I got as far as connecting a 10-base2 card to a fiber converter > > > >> fishing out both ends of the fiber on the reel > > > >> and terminating with 3M (?) hot-melt end. It worked nicely but > > > >> 10 Mhz isn't straining fiber very much. The good thing about > > > >> fiber is the > > > > > > > >low > > > > > > > >> error rate; something around 1E-12. I just disposed of the > > > >> converters a few days ago. > > > >> Still have several Km of fiber and a few connectors. 10-baseT > > > >> works just fine thru conduit buried between desktop > > > >> (house) and shop. About 35 m. > > > >> > > > >> Dave > > > > > > > >I found, at newark/element14, some more fiber fittings, in this > > > > case a > > > > > > > >board mount cover for a 603 sized smd led that the fiber can be > > > > plugged > > > > > > > >into, takes 2mm od fiber, snap fit in board holes, at $0.17 a > > > > copy from > > > > > > > >Bivar. Found some fiber but in 10" lengths, assembled, so still > > > >looking. > > > >The key brand name seems to be Bivar for the hardware. 603 size > > > > smd leds > > > >are similarly priced. I did find an smd phototransistor, but its > > > > target > > > > > > > >is not centered in the package. Not a major problem since I'll > > > > probably > > > > > > > >be designing the pcb, but it would be nice to use the same pcb > > > > pattern on both ends. Since Bivar has a phone numnber in the > > > > pdf, I'll see if I > > > >can contact them Monday. Hopefully its still a good number. > > > > > > > >> On 04/21/2017 01:53 AM, Erik Christiansen wrote: > > > >> > On 20.04.17 14:51, Gene Heskett wrote: > > > >> >> The led makers have now had 40+ years to design such a > > > >> >> package, > > > > > > > >and > > > > > > > >> >> I fail to understand why it has not happened. > > > >> > > > > >> > Somewhere near the bottom of my junkbox is an envelope with a > > > >> > pair of Siemens opto-link (real product name long forgotten) > > > >> > devices, which came out around 35 years ago. They're small > > > >> > grey rectangles with through-hole pins, and a fibre entry > > > >> > with ring-nut (like on a collet holder) on one end. Dunno if > > > >> > they're still marketed, though. > > > >> > > > > >> > At Digi-key, this Broadcom offering looks just like one end: > > > > > > > >https://www.digikey.com/product-detail/en/broadcom-limited/SP0000 > > > >638 > > > > > > > >> >58/516-2872-ND/2220931 > > > >> > > > > >> > But that would leave the rest of my coil of shielded > > > >> > twisted-pair (for RS485) cable gathering dust. With 7v of > > > >> > permissible common-mode, and differential transmission for > > > >> > noise immunity, what more is really needed? RS485 > > > >> > transceivers are around $2 to $3 IIRC. (I saw some for 25c > > > >> > today, but they were surplus stock of a now obsolete device.) > > > >> > > > > >> > Erik > > > > > > > >----------------------------------------------------------------- > > > >--- > > > > > > > >> >---------- Check out the vibrant tech community on one of the > > > > > > > >world's > > > > > > > >> > most engaging tech sites, Slashdot.org! > > > >> > http://sdm.link/slashdot > > > >> > _______________________________________________ > > > >> > Emc-users mailing list > > > >> > Emc-users@lists.sourceforge.net > > > >> > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > > >----------------------------------------------------------------- > > > >---- - > > > > > > > >>-------- Check out the vibrant tech community on one of the > > > >> world's most engaging tech sites, Slashdot.org! > > > >> http://sdm.link/slashdot > > > >> _______________________________________________ > > > >> Emc-users mailing list > > > >> Emc-users@lists.sourceforge.net > > > >> https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > > >Cheers, Gene Heskett > > > >-- > > > >"There are four boxes to be used in defense of liberty: > > > > soap, ballot, jury, and ammo. Please use in that order." > > > >-Ed Howdershelt (Author) > > > >Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > > > > >----------------------------------------------------------------- > > > >---- --------- Check out the vibrant tech community on one of the > > > > world's most engaging tech sites, Slashdot.org! > > > > http://sdm.link/slashdot > > > > _______________________________________________ > > > >Emc-users mailing list > > > >Emc-users@lists.sourceforge.net > > > >https://lists.sourceforge.net/lists/listinfo/emc-users > > > > Cheers, Gene Heskett > > -- > > "There are four boxes to be used in defense of liberty: > > soap, ballot, jury, and ammo. Please use in that order." > > -Ed Howdershelt (Author) > > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > ------------------------------------------------------------ > > ------------------ > > Check out the vibrant tech community on one of the world's most > > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
