The internet, crammed with spam, the dumbing down via false histories and "facts", a vast library, but tainted - read it with a block of salt.

Then there are those sneaky quiz cheaters, surprisingly mostly from the UK, who are using PDAs in the classroom. The teachers must think those students have a fancy calculator. They will e-mail me with questions such as; What do the initials CPU stand for? What is the reason for using opto-isolation in a PLC circuit? Many more Q’s right off their quiz sheet. They must think I am poised at the keyboard ready to answer. Nice try.

The hacking and the tracking - I had been exchanging phone calls and e-mails between two potential sociable clients when something arrived titled "Want to see a picture of my girlfriend?" I clicked on it, had second thoughts and clicked on delete. Too late, the first thing the virus or worm did was cancel delete. I’ll spare you the ugly details.

I’m an old DOS dog use to a hard drive patiently waiting for my command. Now who knows what it’s doing. Have we lost control of our own computers? I received a one paragraph e-mail about a PLC software job in Chicago that had four pages of HTML code hooked to it. I received a three page contract from another source that had a listing of every directory, err folder, on the guy’s hard drive. I guess I should not judge a man by his folders.

I apologize to all those whose e-mails fell in a large pothole on the information super highway, or were thrown out with the bath water, or taken for a quiz cheater. If you try again, I will try to respond in a timely manner.

Corrections:

This site is 3 years old and I’ve just discovered I’ve been claiming PLCs can hook up to POX sensors. I suppose they could be hooked up to germ detectors, but I meant PROX sensors (Proximity switches usually sensing a metal part or cylinder position on the assembly line).

The article about step motors is missing a reference to an article in the March 93 issue of Popular Electronics by Charles Rakes that removed the mystique about how the motors work.

-Dick Profitt 10/02

Since its foundation, Profitt Technical Services has aided in the instruction of several hundred students. Many of these students are midway to retirement as valued employees who know and like Mitsubishi automation products and have served their company well with Ladder Logic programming, trouble shooting, improvements and additions as a result of Dick's initial teaching.

In addition to PLC training classes, Profitt Technical Services also offers programming, program trouble shooting, electrical trouble-shooting and training. In his free time, Dick authors his own technical yet humorous publication, Scan Times. Find articles from past issues of Scan Times, in our complete site map on the left of every page.