[BC] need a NON-technical explanation

[David L. Hershberger]

Richard B. Johnson writes:

> The engineering joke at the time was a Hz to c.p.s. conversion chart with 
> Hz as the ordinate and c.p.s. as the abscissa. It, of course, was a 
> straight line starting at the origin and ending at the limit.

I remember seeing an article where it was argued that Charles Proteus 
Steinmetz was much better suited than Hertz for the honor of the new unit of 
frequency. Hertz, after all, had shelved the phenomenon after he discovered 
it. So it was proposed that the unit of frequency, rather than being named 
"Hertz," be named the "Charles Proteus Steinmetz" instead. And since that 
was unwieldy, the unit would be abbreviated CPS. So a kilocycle per second 
would become kcps instead of kHz. And a megacycle per second would be a 
Mcps. You get the idea.

As for wavelengths vs. frequency, there are some inconvenient relationships 
between the two. Let's say you want to discuss spectrum in terms of 
wavelength. Assume your transmitter is on 540 kHz (555.171 meters). You 
modulate with a 10 kcps tone (that would be a 29.979 kilometer tone). Then 
your upper sideband has a wavelength of 545.077 meters and the lower 
sideband is 565.646 meters. Where the confusion comes from is that the lower 
sideband is 10.475 meters away from the carrier, but the upper sideband is 
10.094 meters. The two sideband displacements are not equal when measured in 
meters. And they bear no simple relationship to the 29.979 kilometer tone. 
And instead of calling them upper and lower sidebands, maybe they should be 
called shorter and longer sidebands.

And channel spacing (10 kcps) at the low end of the band (540 kcps) is 
10.094 meters, but up at 1.6 Mcps it is only 1.178 meters. Isn't that 
confusing? No wonder we went to using the reciprocal instead.

Dave