On Wed, 1 May 2013 17:50:45 -0400, "Tom Del Rosso" <email@example.com> wrote:
> >Artemus wrote: >> > >> The same thing was done with the hand held microphones of CB >> (and probably other) radios in the 70's. A metal plate was added to >> increase the "heft" and assumed quality of the mike. > >It probably also prevented the coiled cord from springing the mic out of its >holder when you put it down.
It's much more complexicated than that and it didn't originate with CB. Way back in the late 1950's and early 1960's, there was a TV show called California CHP with Broderick Crawford. (Yes, I'm showing my age). <http://www.youtube.com/watch?v=2l3jYfV8BtQ> To be seen talking on the radio, a new innovation in the 1950's, he was usually standing outside his Buick, talking into the Motorola microphone. When done, he would often would throw the microphone into the vehicle, where it would presumably land on the seat. That's because the "persuader" microphone of the era was made out of heavy cast zinc, had a rather large heavy carbon microphone element, and included a really heavy duty coil cord, more suitable for an electric power tool than a microphone. It was good, reliable, and survivable.
Enter the 1970's and Motorola decided that smaller and lighter radios needed smaller and lighter microphones. Never mind that there was no correspondent shrinkage in the size of the users. The new mic was made from light plastic and had a light dynamic mic element. The heavy duty coil cord didn't change. The result was when the typical Broderick Crawford wannabe would release the microphone, the tension in the coil cord spring would launch the mic towards the pre safety dashboard and crack the plastic case. When I was running a 2-way radio shop in Smog Angeles area, I was forever replacing Motorola microphone cases for customers.
The initial Motorola solution was to add some weight to the mic, but that made things worse. The Motorola mic didn't have much space for much added weight, so the mic slammed into the dashboard with even more force. Eventually, Motorola ran out of heavy duty coil cords, and installed something lighter. The problem was they also switched from a decent rubber coil cord, to a not so wonderful plastic coil cord, which would crumble into small pieces when frozen. It took about 10 years for Motorola to finally get a reliable microphone. The plastic was thicker, the shell was solvent welded together, some weight is added inside, it was filled with waterproof foam, and the coil cord could easily be disconnected and replaced with an RJ45 connector at both ends. The mic element was now electret, but still simulated a carbon microphone. At the time, replacing the chronic broken locking tabs on the RJ45 connectors was the only remaining problem. GE and RCA were not far behind Motorola and successfully repeated all of Motorola's mistakes and subsequent fixes.
I'm not sure what point CB radio discovered adding "heft" to the microphone. Oddly, as CB radios shrank, CB microphones became larger and heavier. There's some odd psychology involved, but since this is a family newsgroup, I won't go there.
Anyway, the weight added to the microphones had little to do with marketing, and more to do with users trying to emulate the Boderick Crawford style of microphone launching.