Sunday, July 27, 2014

College Majors

Personally I didn't have a clue back when I was doing college.  I was lucky enough to be able to go back to college, after a hitch in the Air Force, and get a degree in electrical engineering, which served me well thruout my working career. 
  To choose your major wisely, you really have to know what you want to do after graduation.  Of course, if you are wondering about what to major in, you probably don't have a clue about your future career, again, I didn't at the time.
   In the usual case, when you don't really know what you want to do with your life,  you oughta keep your options open.  College majors fall into four catagories.  science sechnology, engineering and mathematics (STEM) , liberal arts , job training (business, education ,pre med, pre law, computer science) and nothing majors (gender studies, sociology, political science).  You don't want to rule out anything too early. 
   Which means you want to take calculus freshman year.  All the STEM majors are calculus based.  Without calculus the course material will be meaningless to you.  If you don't have calculus, the whole STEM field will be closed to you.  Smart planning doesn't close out a broad avenue of study for no good reason.
   Calculus isn't hard.  The concepts are totally new to students coming up from algebra and trig, and can be hard to accept.  They aren't hard to remember, but  they are aren't readily believable like two plus two equals four, something everyone accepts.  Some people simply cannot get their heads around calculus, no matter how hard they try.  A lot more people shy away from it 'cause "math is hard".  The forward looking student ought to try it, 'cause without out calculus, whole realms of learning are forever closed to them. 
  Calculus requires preparation in high school.  You need algebra, perhaps two years of algebra, and trigonometry.  A lot of calculus work uses trigonometric functions, equalities and transformations which you have to know.  Now a days, schools tend to label the trigonometry course "pre-calculus" but it is still trig.  A course in plain geometry is nice, but not essential.  If you don't get this stuff in high school, you will have to pick it up in college, before you can take calculus.  If you don't do calculus until sophomore year, you won't be able to take STEM courses until junior year.  Which is pretty late.  So start planning in high school and get your math courses in early. 
   If, by junior year, you decide to major in liberal arts or job training, go for it.  But you will have the option of STEM majors if you want them.  Which is a better place to be than wanting to do a STEM major but being locked out of it thru lack of calculus.

Friday, July 25, 2014

Electricity for homeowners

Just a few bits of wisdom picked up over the years.  Understand, electricity can be dangerous, can burn your house down, so if you have any doubts about a do it yourself project, you ought to call a pro. 
   Juice comes into the house from the street with three wires.  Two hot wires, color code black, and a neutral wire, color code white.  The two hot wires are 120 volts, alternating current (AC) which means the voltage goes up and down, current goes back, and forth 60 times a second.  The two hot wires are 180 degrees out of phase with each other, which means when one wire is plus, the other is negative, and vice versa.  Which means you have 220 volts measured from one hot wire to the other.  Things like electric stoves, electric car chargers, big power tools , central air, and the like  get 220 volt power.  It is customary to run a special branch circuit for each 220 volt appliance.  The familiar branch circuits are all 120 volts, which is obtained by using one hot (black) wire and one neutral wire.  The hot wires each measure 120 volts to the neutral wire. 
  Black to brass, white to chrome.  Old electricians proverb.  The screws on the sockets and light fixtures are alternately brass and chrome.  Wire black to brass and white to chrome and you won't get hot and neutral switched around. 
   Fuses, or circuit breakers are there to protect the wires, not the appliances plugged into the branch circuit.  Should a short circuit occur, massive amounts of current will flow in the wires, which are buried in your walls, and heat them red hot, setting the house on fire.  The fuse or circuit breaker will open the circuit and cut off the current before anything bad happens.  New houses use #12 wire for branch circuits which can handle 20 amps.  Older houses had lighter #14 branch circuits which called for a 15 amp fuse. 
  Never fuse the neutral.  Another old electricians proverb.  It's complicated, and I cannot explain it without several diagrams.  So just take it from me.  Don't fuse the neutral.
  Treat neutral as if it were hot, i.e. don't think it's safe to touch.  A whole bunch of common faults can make neutral become hot and shock the bejesus out of you. 
  Run a safety ground color code green on all new work.  Safety ground protects against shock should the appliance insulation fail and allow a hot wire to touch the case, making the case hot.  If the case is connected to safety ground, all sorts of current will flow, and the fuse will blow, removing power and making the case safe to touch.  Back at the fuse box, the green safety grounds want to be connected to a good earth ground, say a 4 foot iron pipe driven into moist dirt, or the cold water pipe coming in from the street, before the water meter. 
   Most electric codes call for the neutral to also go to earth ground.  This is worth checking out.  One of the houses I owned over the years came to me with the neutral ground clamp rusted clean off and dangling in midair. 

Thursday, July 24, 2014

Flight safety or political retailiation?

Ted Cruz accused the Obama administration of  forbidding US airlines to fly into Tel Aviv in order to pressure Israel over the Gaza strip.  He might have something there.  The flight ban was laid on after a Palestinian rocket hit within a mile of the airport.  Which is not nearly as dangerous to aircraft as a SAM. 
   Fortunately FAA dropped the flight ban to Tel Aviv after two days, which makes me think maybe they were really thinking about flight safety rather than retaliation. 
  That a responsible US Senator would make such a charge indicates a major loss of trust with the Obama Adminstration.

Heat, not light, "finds" the Lois Lerner emails

To find something, you can turn on the lights or turn up the heat.  In the case of Lerner's missing emails, heat seems to have been more effective than light.  Under extreme heat IRS has just admitted that maybe Lois' emails might be available after all. 
   In actual fact, the IRS excuses about crashed hard drives are BS, even though the newsies have fallen for them.  The emails all travel over the office local area network (LAN) and thru central email server computers.  Which are probably running Microsoft Exchange  Those servers can keep a complete record of every email ever sent, neatly sorted by sender, receivers and date.  In the IRS, which might need an old email to either prosecute tax payers or defend itself in court or in front of Congress, it is inconceivable not to have central archiving of email.  Any IT guy will tell you that you cannot depend upon users to kept decent (or any) records.  IT has to do the achieving centrally.  
   Keep the heat on.  Tell that smarmy new bald headed IRS chief to produce Lois' emails or go to jail for contempt of Congress. 

Wednesday, July 23, 2014

Do they have the votes? Now?

Vast excitement on the TV news about the Obamacare court cases.  The DC circuit court held that the plain language of the Obamacare law is binding.  Even though the plain language, citizens in states without state run exchanges (most citizens) don't get government subsidy, seems wrong.  Probably is not what the Congresscritters intended.
  Later that day, another Federal circuit court held the other way.  All the TV newsies are talking about taking it to the Supremes and that will take a year.  All the talk is about resolving things in the courts.
   Little to no talk about having Congress fix it.  Congress could pass a law saying that section yadda-yadda of the Obamacare law is hereby amended to read as follows...."  Would only take a day or two.
  But, does anyone have the votes to pass something like that?  Would Narry Reid allow a vote on it? Polls show that by 55% to 45% the voters want Obamacare to go away.  They think Obamacare is causing Great Depression 2.0, jacking up medical costs, making jobs harder to get, and preventing them from going to the doctor and hospital that they have always gone to.  Clearly there is reason to worry that opening up an amendment to Obamacare might give its opponents a chance to kill it for good.
   So, right now,  the newsies (all in favor of Obamacare) are trying to steer the matter to the Supremes, where they think there is a better chance for it than in the Congress.
   Real believers in democracy, those newsies. 

Tuesday, July 22, 2014

Flight Examiner SAM

At Korat Royal Thai Air Force Base (Thailand) one would see pilots wearing a shoulder patch with that logo.  That was 1968 and we were flying F105 fighter bombers up to Hanoi twice a day, every day.  SAM in those days was SA-2, a not very mobile system.  A SAM battery consisted of several launchers, a couple of radar trailers, some hootches and "stuff".  The Russians had provided the more up to date tracked vehicle mobile SA-6 to the Egyptians in time for the 1967 war with Israel, but the North Viet Nam comrades didn't have it yet. 
   SA-2 was the SAM designed to get U-2 photo recon flights operating above 70,000 feet.  This resulted in a big rocket, about the size and dimensions of a telephone pole.  It took the rocket motor quite some time to boost this heavy missile up to real speed.  At low altitude, the F105 could out fly SAM.  Pilots who survived this feat of airmanship got to wear the patch. 
Once SAM was at altitude, with much of his fuel burned off, he was deadly fast, cannon shell fast, too fast to dodge, almost too fast to see.  So the effect of SAM was to force us down, into the ground fire.  Instead of going in at 25,000 feet, well above any kind of ground fire, we had to fly at  5000 feet.  One pilot put it thusly  "Even the kids have slingshots." 
  SAM was a radar guided beast.  No heat seekers for him.  We carried electronic countermeasures pods to confuse Mr. SAM.  The early ones were straight noise jammers.  The later QRC 160 pods attempted to spoof SAM by picking up his radar pulses, amplifying them, messing with them, and squirting them back at SAM's radar.   A weakness in QRC-160 was the occasional pod that started talking to itself.  The receiver would pick up a bit of noise, it would amplify the noise and transmit it.  The transmit antenna wasn't far from the receive antenna (how far away can you be when the whole pod was only ten feet long?)  The receiver would pick up the transmissions, amplify them again, transmit them again, and within seconds the pod transmitters would be blasting a full power signal.  This worried the aircrew, who feared that the comrades could track them and launch at them.  So the talkative pods were sent to my ECM shop to shut them up.  There was nothing in the technical order about loud mouth pods, fix there fore.  So after a lot of trouble shooting and testing, we resorted to ordering some parts that we knew base supply didn't have.  After waiting about 30 days for parts, we were allowed to ship the talkative pods back to depot, which got them out of our hair. 
   The SAM that took out the airliner is a descendent of  SA-2.  About third or fourth generation.  SA-2 was followed by SA-6.  SA-6 managed to pack 3 missiles and the radar into a single tracked vehicle.  SA-11, the one suspected of airliner shooting,  carried six missiles and must have had a new electronics and radar suite, came after SA-6.  I have heard of an SA-17, but know little about it.  SA-2 fifty years ago would hit airliners at 33,000 feet, no sweat.  The later models must be just as effective. 

Monday, July 21, 2014

Israeli Travelog, Bebi gets favorable TV coverage

Public television ran a nice "travel in Israel" piece on Sunday.  It had boating down the Jordan, views of Jerusalem, the Dome of the Rock, the Wailing Wall, Masada, and spectacular scenery.  For extra points, they had Benjamin Netanyahu, Israeli prime minister, acting as host.  Bebi knew the history and the archeology of all the places, told  interesting stories, and he came across as a well educated and thoughtful man.  In fact, I was impressed at how nice the TV coverage was for Bebi.  Dunno just who set up this TV deal, but it did Bebi a lot of good.  It was probably filmed before the current Gaze dustup, but it was nice coverage.  Good travel log too.