On Monday, February 20, 2012 10:53:17 PM mel...@earthlink.net did opine: > Honeywell datasheets suck...
Yeah, I'd compare that vacuum to the one about halfway to Alpha Centari. > The only relatively good picture is the schematic and the view on the > left is from the top and the actual basing they show is from the > bottom. > > The polarity they show on the top corresponds to the + S for Vcc and + E > for anode/Kathode. At least that is the way I am looking at it. Which is how it is in the board layout if you looked. > Not > sure why they used a K instead of C, but the + sign does follow the > power for the sensor and the anode of the led (if you rotate the basing > view 180 degrees). The forward voltage for the led will be 1.6 volts! I believe that may be the maximum self destruction voltage, assuming sufficient is available to reach that. At my dvm's diode range, I checked 6 of them, 3 had never seen power, and they all read a couple of millivolts from .989 volts forward, and with nearly 21 ma now flowing its just a few millivolts above 1.24 volts. > What you may be seeing using the DVM is a minute voltage drop based on > the reverse leakage current (won't be much). And it wasn't much, <20mv. > > best regards, Steve Thatcher > Electronics Engineer Well I hate to look in the mirror and point fingers, its so damned embarrassing, but what else can I do? Turn in my C.E.T. certificate? Oh no, not THAT! That test, in 1972, was 100x the test for a 1st phone was in 1962. When I turned it in in about 45 minutes elapsed time (the test admin had allowed a 3 hour period to do it) he asked if I was sure & I said that was as good as I could do. Then he started scanning the answers, with his eyebrows going up about 1/2" a page. He wouldn't say other than National had to check it officially. The certificate showed up in the mail 2 weeks later & when I called the test admin, a prof at the local community college, he allowed I'd missed 2 out of 125, about 20 less than he had ever seen before. I thought at the time he must be easily impressed & wondered how well the students he was teaching that class did when they tested, but I guess I got that answer when I talked to Ron Crow about 5 years later. I am NEB-118, 5 years later they had only issued 4 more certs. That did impress me. What was wrong? Working from one of those 8 ounce bags of 5 or 10 each tape bound 1/4th watt R's the shack has peddled for years, I spotted the 150's thru the bag, but when my hand came back out of the bag, it had 150k's in it, third strip a pale yellow. So, swapping them out, and they actually read 147.7 ohms this time, I now have 3.098 volts across the resistor in series with each LED, and the led voltage is showing at about 1.24volts for all 3 of them. So now I have 3.098/147.7= 0.0209 amps thru each one, and they switch as expected when the slot is blocked. These 1 oz circuit boards aren't really made tuff enough to be repaired, so there is now 3 pieces of wire wrap bypassing broken traces, but it will work just fine once the thing is mounted in the lathe & the cover installed on the headstock & nobody but this group will ever know the secret. ;-) TBT, I really need an iron with about a 1/10th sized tip & only maybe 10 watts for this, that temp controlled XYTronix I've had for around 27 years now, while a good iron, wasn't really designed for this small work, and at my age, neither are the nerves and eyes without the illuminated magnifier I also have. I can get 1/64th inch tips which would help but the only decent one I could find for this is a 1/32nd inch, bigger than these joints. I need to go shopping to see whats available if I am to make too many more of these. But I'm probably the only idiot that would try to cnc a 7x12 so even if I advertised, I doubt I'd make a sale. I hung it off the edge of the table so it could burn something up if it failed in the night & left it powered from a switch mode 5 volt, 1 amp wall wart supply as an overnight smoke test. 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> Banacek's Eighteenth Polish Proverb: The hippo has no sting, but the wise man would rather be sat upon by the bee. ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
