ELEC 241 Lab

Chapter 1

The Lab PC

Logging In

In order to use the Lab PC, you must first login. Your username will be the same as on Owlnet, but you will have a different password. See your labbie or Terry Graham to get your initial password (you will have to change it the first time you login).

If you have run the "pcpasswd" program on Owlnet, you will be able to access your Owlnet files from the Lab PC. For this to work, you must choose the same new password for the Lab PC as you did for pcpasswd.

Here are the steps for logging in:

  1. If the screen is blank or displaying a screen saver, press any key. The monitors have a power shutdown feature, so it may be necessary to wait a few seconds for a display to appear.
  2. You should see a dialog box asking for your username and password. Enter these (using TAB or the mouse to move between fields) and click "OK" or press RETURN (use TAB to move between fields).
  3. If this is the first time you have logged in, you will get the message: "Your password for unilab has expired. You must specify a new one to log on." Click "OK" and complete the dialog to specify a new password.
  4. You will get a pair of dialog boxes relating to mapping your Owlnet directory to the Lab PC. The first is titled "Connecting O: to //long-eared/homes." The second asks you to "... supply a password to make this connection." If you have run "pcpasswd on Owlnet (see above) enter the passwd you specified then. If not, click "Cancel" and answer "yes" to the subsequent dialog.
  5. At this point you should be successfully logged in.
  6. When you are finished, be sure to log out: Select "Shut Down" from the Start menu and choose the option "Restart the computer." PC-Rdist will run to reset the software configuration, and the computer will reboot.

Available Software

There are three software packages that we will be using:

Netscape:
Intended primarily for displaying the online Lab Manual. Also useful for running the color code calculator or surfing the web when the labbie isn't watching.
Matlab:
Useful for plotting data taken with the traditional instruments. Also used to compute spectrograms and do digital signal processing (DSP).
Labview:
In conjunction with the Data Acquisition (DAQ) card, converts the PC into a programmable lab instrument, able to perform both the functions of the traditional instruments, as well as functions that they cannot (e.g. spectrum analyzer). Also used to record and play signals digitally, to implement feedback control laws, user interfaces, etc.

The Online Lab Manual

The 242 Lab Manual actually exists in two forms: the printed manual and the online manual (what you're reading now). The content is largely the same but the online version has a few extra goodies. Being an HTML document, it has hypertext links between related sections (in the printed version, these are underlined so you can tell that there's additional information available online). It has additional photographs showing closeups of some components, circuits, and techniques. And, of course, the pictures are in color.

It also has active links for starting up some of the software packages used in the Labs. This means that instead of having to find the program icon and then navigate through the directory tree to find the configuration file, you just press the button and the program starts up, ready to go.

When you start up Netscape on one of the Lab Station PCs, you will get the Lab Station home page. Click on "ELEC 242" under "Lab Manuals" to go to the 242 lab manual. You don't have to wait until lab to use the online manual. it's available from the 242 home page at http://www.owlnet/~elec242.