CPR Certification

Today I attended a CPR and First-Aid Training session at Ivy Tech for faculty and staff. I was the only registered person of six to attend, so I had plenty of time to work on the CPR mannequins and learn to use an AED under direct supervision. At the end of the period I paid $7 for a two-year certificate from the Americani Heart Association.

There were some interesting related bits of information. Indiana has a "Good Samaritan" law, so my CPR efforts are protected from gross litigation; however, EMTs do not get the same legal protection, which is apparently one reason why they cannot even administer aspirin in Indiana. It is now considered acceptable to break the breastbone when pushing on the adult victim's chest; if you've not broken it, you probably have not pushed deep enough to cause the heart to pump effectively.

Anyway, I am quite glad I attended the course.

Saraga

Yesterday I made my first trip to Saraga, massive international grocery in northwest Indianapolis. It was recommended to me by a Japanese friend as having the best prices he's seen though there's little room to improve on costly Japanese imports. That said, I did buy an oden set that was pretty nice and a good daikon for $0.99.

One of Saraga's charm points is its massive produce section. There were some unusual items, including more types of pears than I have seen before.

Another is the sheer range of stuff. The Middle Eastern section in particular was quite large, but I couldn't find any laban or leb'n, a yogurt-like drink that works wonderfully with dates. There were some interesting African foodstuffs too.

The next time I go, I do plan to try mate tea soda. It does not sound that thrilling though I like mate tea. However, I am quite curious about the soda's taste.

最新計算機 / Newest Calculator

It turned out that my TI-89 cannot be used in linear circuit analysis II, because it is a graphing calculator. I bought a new calculator mainly because I was sick of working with complex numbers (i.e., a+bi) on a standard calculator. A calculator that can handle complex and magnitude/phase math was needed.

A friend bought a TI-36x Pro but I plumped for Casio's fs-115MS, in part because it was in stock at a nearby store and I didn't want to wait. Once I had it at home I worked through the tiny accompanying manual, which shows it does a broad range of things, though I wish it could do matrices.

I have had some frustrations with it, but mainly because it takes time to adjust. One is that I must choose the complex number output setting in advance, as either a + bi or polar form. Storing values is awkward because it took a while to realize that I must store with the Ans key sometimes; otherwise the calculator will perform, again and unwanted, the last operation then store that value, thus storing something you don't want.

All things considered, it is a nice calculator. However, I do wish classes would allow other things. Life would be easier if I could use MathStudio on my iPod on a test.

Coupling Inductor Problem Isn't

For some time now I have had trouble with the INDUCTOR_COUPLING element in Multisim. I would place it after placing my inductors then adjust the coupling inductor's settings for the inductors to be coupled and the k constant. Every time I would get a netlist error.

Tonight I found out why: Using INDUCTOR_RATED inductors with INDUCTOR_COUPLING will result in a netlist error. Use a standard inductor instead then modify it from the Properties pane.

Never ever use INDUCTOR_RATED if you plan to couple inductors!

Mutual Inductance in Multisim

For over a year, I have used National Instruments' circuit analysis and design software: Multisim. I have v12, educational version.

Our current homework is about mutual inductance. In class, we received a quick demonstration on how to do couple inductors in v13:

  1. place your inductors, but remember the dot's location is on the left of the inductor when you first place it, so rotate it to position the dot elsewhere
  2. under "Transformer," choose COUPLING_INDUCTOR and place it off by itself, as it is not connected to your circuit
  3. open that element's properties (Ctrl+M)
  4. under "Value," fill in the fields "Coupled inductors list" (by name, like "L1,L2") and "Coupling coefficient"
  5. finish your circuit

However, once I got home, I couldn't find COUPLING_INDUCTOR, rather COUPLED_INDUCTOR, which is not the same. The Help for v12 says COUPLING_INDUCTOR exists, but it apparently does not, perhaps an intentional omission in the academic version. Eventually I got a v12 file with a COUPLING_INDUCTOR element from someone else, so I've been using that file as the template for my assignments. It was very aggravating to learn that cutting and pasting the element into a new file resulted in a netlist error.

One thing I've done is mark the mutual inductance dots by using colored asterisks placed as text. Multisim seems not to offer a way to display the dots, so that is my solution.

This is what COUPLING_INDUCTOR looks like:

20140201-215313.jpg

I did write National Instruments about the netlist errors I kept getting when trying to link inductors before receive the COUPLING_INDUCTOR from someone. Their technical support should get back with me Monday.