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> DIgikey sells the stuff and its cheap because these parts are used in consumer electronics and produced by the millions. On Sat, Apr 22, 2017 at 1:01 PM, Gene Heskett <[email protected]> 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 <[email protected]> > 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/SP0000638 > > > > > >> >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 > > >> > [email protected] > > >> > 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 > > >> [email protected] > > >> 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 > > >[email protected] > > >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 > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California ------------------------------------------------------------------------------ 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 [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
