Electronic Design

What's All This Toaster Stuff, Anyhow?

Well, I never owned a toaster, but I have owned several kinds of toaster ovens. A long time ago, I had a good GE one. But then Black & Decker took over GE, and while the toaster ovens performed okay, they showed me poor reliability after a while. They would fail shortly after the warranty ran out, and I'd buy another. I soon got tired of this. They would either quit open-circuit, or the heating element would go gablooey. (That's a technical term.) Either way, they were unrepairable. My wife volunteered to buy the next one.

She went out and bought a new kind of toaster oven from Black & Decker. When she got it home, it didn't work at all. She decided to try a DeLonghi toaster oven. It looks handsome, and it seemed to have many nice features. It's a model AS960, now about two years old, and it does seem to be reliable. The only problem is that it doesn't toast.

Whether you put in two pieces of bread, or six, it takes forever to get them even light brown. I have to put it through two "Dark" cycles to get it even light brown. I measured the power, using my watt-meter (ELECTRONIC DESIGN, May 13, 2002, p. 86), and it was barely 1200 W on our 112-V line. Not very healthy.

I decided to add a booster transformer to get it up to over 1400 W. I went down to Halted Specialties Corp., which had many small transformers—and a few BIG HEALTHY power transformers. Surely one of them would put out 10 extra V! I got a few and doped out which windings would do what. I wired three 115-V primaries in parallel and three 3-V secondaries in series. Lovely (surplus) transformers—this rig would put out 14 A and stay cool.

I set up some standard bagel pieces. I set up my wattmeters and voltmeters all around the toaster, along with the transformers. Sure enough, adding the boost transformers kicked up the power from 1260 to 1470 W. The heating elements got red. I prewarmed the toaster for three minutes, let it cool for one minute, and toasted some bagel pieces at 1460 W for exactly three-and-a-half minutes.

I let the toaster cool off for one minute and toasted a matched set of bagel pieces at 1260 W—to get them exactly the same color. And the time was—exactly three-and-a-half minutes. H'mmm. I'm not sure what went "wrong," but I'm glad I ran the experiment very carefully. Maybe this weekend I'll buy a loaf of white bread and repeat the experiment—1260 W, then 1460, 1260, 1460 W... I may learn a trick. So if you buy a piece of consumer electrical equipment, don't be surprised at anything. Don't even be surprised if you have to add a little helper to Ohm's Law.

See the figure

RELATED STORY - There was a guy, George Gobel, who wanted to decrease the time for starting his charcoal broiler. He tried several kinds of boosters, chemicals, etc. Finally he hit on the ultimate charcoal starter: LOX. He would apply a small flame under the charcoal. Then from the end of a 10-ft pole, he would pour a few gallons of liquid oxygen over the charcoal. His camcorder could not record any actual details, as the flame was too bright. But in three seconds, the charcoal was hot enough to broil meat. Think of all the time you have wasted trying to get charcoal started. Now you will never waste more than three seconds! There is one minor drawback: If you use a cheap metal grill, it will burn right through. You may find that a porcelain or ceramic grill lasts longer... Hey, maybe I should do that with my toaster! The URL is www.doeblitz.net/ghg/.

Comments invited! [email protected] —or add your comments online at ED Online 10940 ---or: Mail Stop D2597A, National Semiconductor P.O. Box 58090, Santa Clara, CA 95052-8090

Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.