Denton’s Corner
Today’s Bit of Whimsy
There was a fine android named Paul
Whose speed was reduced to a crawl.
He said, “Please plug me in,
My battery’s thin.
I need some amps from the wall”.
Now THAT Was A Ham Project!
One of the most interesting and brilliant hams in the world was Grote Reber, W9GFZ, of Wheaton, Illinois.
In 1937, the world was in the grip of the Great Depression. Resources were scarce. What’s a ham to do? Grote decided to see if he could bounce a ham signal off the moon, and receive an echo. To that end, he built a partially steerable 9 meter parabolic dish antenna in his back yard, and designed and built his own transmitter and receiver. Fortunately for the world, his effort was in vain. Moonbounce was not accomplished for another 12 years, and required power levels unavailable to amateurs.
Why was this fortunate?
With no echoes from the moon, he repurposed the 9 meter dish to look for interstellar radio emissions. He knew that in 1933, Karl Jansky had discovered radio emissions at 20.5 MHz emanating from the center of the Milky Way. According to the then current theory, higher frequencies should show much more intense radiation (Google “ultraviolet catastrophe”). If 20.5 MHz whispered, 3300 MHz should roar. Could he detect stellar radio signals?
Grote designed and built a receiver for 3300 MHz, but could not detect any stellar emissions. I have no idea how you would build a receiver for such a high frequency using 1930s technology, but he did it. The net result of his finding that there was nothing to hear at 3300 MHz called into question the prevailing theory of how interstellar radio emissions should behave.
Nothing to hear at 3300 MHz? He then designed a new receiver for 900 MHz. Again, no luck.
In this case, the third try was a charm, and his new 160 MHz receiver began to yield definite results, and he produced the world’s first radio source map of the sky.
Grote did all this in real ham fashion: no sponsorship, self financed, mostly created through his own labor, and done just to learn something, while holding down a full-time day job.
He did succeed in publishing his results, but not without controversy. His article was reviewed for publication by electronics experts and by astronomers. The astronomers couldn’t understand the electronics explanations, and the electronics experts could not understand the astronomy portion of the article. In the face of such uncertainty, the article was still published and Grote Reber became acknowledged as the father of radio astronomy.
For about a decade, he was the only radio astronomer in the world. Eventually he was joined in the radio astronomy field by his friend, John Kraus, W8JK who built the “Big Ear” radio telescope at Ohio State University. But that is a story for another day.
73 for now,
Denton W7DB