Electronic Design

Bob's Mailbox

Dear Bob:
Here are two more examples of contrariness from professional broadcasting:

The Germans: Professional tape recorders, like the Telefunken M 15 A still in use in German broadcasting stations, have a tape transport for reels of tape with the magnetic layer on the outside of the (open) reel. But internationally, the magnetic layer of the tapes is on the inside of the reel. This seems to stem from the first AEG tape transports built in 1936. The reason for this approach may have been that there is more space available compared to the space between the reels. And space was certainly needed in the beginning, because of the rather bulky tape heads. (This seems plausible—but ODD!! /rap)

Regarding tape movement, this is and always has been "normal" from left to right. (You mean you haven't found anybody to do this backwards? In my kitchen, I have an inexpensive tape machine in which the cassette gets inserted into the door UPSIDE DOWN. Both spools turn CCW during normal playing. But as the tape is at the TOP, it's actually going from right to left as it goes past the heads! That doesn't change the tape flow. It just means that the tape mechanism is upside down. And of course, there are reversible tape decks in which the tape can go alternately LEFT or RIGHT. /rap)

Initially, a tape speed of 1 m/s was used in Germany (Telefunken K1 of 1936) and later 77 cm/s (Telefunken K7 of 1940). Later, after the war, tape speeds based on inches per second were and are still being used—7.5, 15, and 30 in./s. (Not only 7.5, but 3.75 and 1-7/8 in./s. Almost all audio cassettes are at 1-7/8 in./s. Except some books on tape are 15/16 in./s, I think. /rap) It is interesting to note that 30 in./s (76.2 cm/s) is quite close to the 77 cm/s used in 1940—a period of time during which Germany certainly never would have adopted anything based on inches. (And in 1940, Germany wasn't exactly on the committees to set up international standards! In fact, they just wanted to IMPOSE their standards as universal! /rap) I believe tape width was initially only 6 mm, compared to 6.25 mm (1/4 in.) as used today.

The British: In professional broadcasting mixers from Britain, it was (and still is?) common to find a fader arrangement where the fader at its top position would give zero volume. All mixing consoles in use elsewhere at that time ('70s and '80s) have their zero volume position at the bottom end. Admittedly, the British way of doing this has the advantage that it will hardly be possible to fade in a signal inadvertently, since this would require pulling rather than pushing—which may happen more easily. Reference: Penny and Giles Conductive Plastics Ltd. Audio Products Catalogue of 1983—1500/1900 series faders with the options of "fade up" (infinity towards operator) or "fade down" (infinity away from operator).
via e-mail

Hmmm...Yes, that is an OBSCURE kind of contrariness! Thanks for the stories!—RAP

Dear Bob:
I have just read your column, "What's All This Vice-Versa Stuff, Anyhow? (Part II)" (Electronic Design, Aug. 9, p. 107).It takes a while for it to arrive here in Australia! I just thought I would add some clarification to the "which side of the road do you drive on" discussion. If my memory serves me, there was an international meeting in 1903 to provide some standardization to automobiles. At this time, it was decided that the driver should sit on the left side of the vehicle and drive on the right side of the road. (Here, your arguments may figure in).

After this meeting, Royce (later of Rolls Royce fame) convinced the British Government that if they switched to the left side of the road, it would keep all those nasty foreign cars out of England and, of course, help bolster their English industry.
via e-mail

Charming! Very amusing! YOU are the first guy to tell me this! But England had been driving on the left for well over 100 years, officially, and over 1850 years at that point unofficially. So maybe Mr. Royce was just deciding to REFUSE to change over? Considering the turmoil a changeover would have made, I can hardly blame them for staying put! I mean, cars and drivers are hard enough to change over. But getting the HORSES to go along would have been IMPOSSIBLE!!

Dear Bob:
This is in response to the baseball-throwing letter in "Bob's Mailbox," (Electronic Design, Oct. 28, p. 100). I was not impressed with the presentation of evolution as fact when we all know that it is, like any idea of the beginning of the world, no more than a theory. A theory full of holes, inconsistencies, and a lot of guesswork.

I recognize that it is a theory many believe as fact, although many also believed at one time that the Earth was flat. For many reasons, some of which are scientific, I choose to believe a different theory regarding the creation of the world. I do not mind a good discussion on the topic, however; but let's not forget that what we are dealing with are theories. To present, or to allow to be presented, evolution as fact is somewhat intellectually dishonest at best.
via e-mail

Todd, you can believe any theory you want to. But if you want to say that the "Theory of Evolution" is only a theory because it hasn't been proven to a shadow of a doubt by facts and complete evidence, then there's no point in debating or arguing. Obviously, we have completely different ideas about what "a theory" is. If you don't want to believe in it, you don't have to.—RAP

All for now. / Comments invited!
RAP / Robert A. Pease / Engineer
[email protected]–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.