Electronic Design

Bob's Mailbox

Dear Bob: I had to laugh at your recent column.* I experienced similar product destruction with my (brand x) air cleaner. Let's see, I lost: all belts and wheels in two high-end (industrial) VCRs—and one a second time. Also, belts in three audio CD players, in a DVD player, three computer CD drives and one

DVD drive, plus a belt in a vacuum cleaner—three times. (Ouch!! That's painful!! /rap) The air cleaner seems to be two appliances in one. It has an ozone generator and a positive ion generator. The positive ions don't destroy anything but make your walls and windows dirty by depositing dirt on them. If I were the litigious type, I'd smell class action.

  • John Spangler (via e-mail)
  • Pease: Well, I can't say I'm in your class action, but I am trying to help by warning everybody. Note that some companies, such as the Sharper Image, will sell you an air cleaner guaranteed free of ozone.

Dear Bob: I was the chief engineer of a Cleveland, Ohio, FM radio station back in the mid-1970s. Inside the transmitter building was the usual high level of ambient noise from the transmitter blowers. To hear program audio I had a fairly hefty receiver and speaker system. One day I noticed that there was something not quite right about the sound.

Pulling the front cover off revealed that the compliant rubber ring supporting the cone had completely disintegrated on both units. (Uh, yeah. /rap) I never actually smelled any ozone, but I'm certain some was being generated by the high potentials. Judging from the September issue article, there must be some pretty elevated levels of ozone in those living spaces to cause the problems mentioned. Sounds like we should be more worried about ozone than radon gas!

  • John Mattesini (via e-mail)
  • Pease: Yeah, but a transmitter has a set of big fans to keep it reasonably cool. And the hot air is then sent out of the building, along with most of the ozone. So it's not as bad there as in some other places.

Hi Bob: I certainly do agree with your comments in "What's All This Wireless Stuff, Anyhow?" (ELECTRONIC DESIGN, Sept. 15, p. 22). Pictures are indeed better on the radio. A few years ago, Stan Freeberg, a once-notable comedian, made a series of commercials for radio, which were broadcast on (what else?) the radio. The purpose of the advertisements was to vividly illustrate the power of the human mind to visualize objects and tasks that would otherwise be impossible to portray on television or other visual media.

Imagine, as did Stan Freeberg, Lake Erie totally covered in whipped cream with giant battleships delivering maraschino cherries! I can actually "see" that in my mind, can't you? (Heck, I got it memorized! It's a classic. But wasn't it a bomber that dropped the cherry on top? I can still see that in my mind's eye. I don't recall seeing any battleships. /rap)

The "eye of the mind" has always been more graphic and demonstrable than any graphic that can be presented. Remember all those radio programs that you and I listened to as kids? How did the "Green Hornet" look to you? How about the squeaking door on The Inner Sanctum?

  • Karl Kanalz (via e-mail)
  • Pease: Man, Inner Sanctum was too scary for me. It made me uncomfortable. These shows were a little too real!

Dear Bob: Your article on "Wireless Stuff" was most amusing. On a similar note, you might want to look at the wired world as well. In the 19th century, we had cable communications. And the system was totally digital. It was called the telegraph.

  • John A. Rupkalvis (via e-mail)
  • Pease: Gee, I don't even have digital cable communications at my house. I do have a telephone, but it's analog.

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