Sunday, May 10, 2015

Boy Genius Blocks Navy Wireless

Commander Albert C. Gleaves U.S.N. of the Torpedo Station in Newport, Rhode Island, had a problem. The government had installed a new wireless station for ship-to-shore communication but in 1906 they were experiencing interference from a nearby amateur radio operator.
My sign was GR. "GR GR GR," they said, "if you don't stop operating that coil, you will find yourself in the jug shortly." I answered by sitting on the key. I was such a nice boy! - Lloyd Manual, Wireless Age, Dec. 1916.

The Nashville American, 22 Feb 1906
The Nashville American, Feb. 22, 1906

The Navy investigated and discovered a teenage schoolboy who had converted a hen house into a "ham shack" and equipped it with a home-made transmitter. The meagerness of the radio set startled the professional wireless operators who examined it. A report was filed with the Navy Bureau of Equipment. Some of the components used to build the set were described in The Nashville American and included:

Friday, May 1, 2015

Experimental Wireless Station 1XX

The Radio Club at Brown University dates to the end of the First World War when the United States government lifted restrictions on the private operation of wireless equipment. Student amateur radio operators formed the new club during the Fall semester in 1919.

An early transmitter used on campus was described as "a ½ KW rotary spark set and a two step amplifier" in the September 1920 QST magazine. One of the call signs used was 1LAU which was assigned to student Herbert R. Grimshaw. The emissions from the crude transmitters used by amateurs during this time caused stations in the same geographic area to interfere with each other. President of the club E. Standish Palmer proposed a system for managing the problem:
"Providence has considerable QRM [interference] to overcome and some sort of a control station is being considered. Palmer suggests different hours for the different classes of communication and a visiting committee to go to the stations of the various amateurs who overstep and tune them up. This is a good idea. Help the young fellows out in every way possible. Make them feel as though we are helping and not trying to dictate to them."
Another transmitter was a home-made set with two vacuum tubes. The alternator used to generate the alternating current is not shown in the photo below. It produces an Interrupted Continuous Wave (I.C.W.) which, like the rotary spark gap described above, was used to send Morse code. These transmitters were not capable of voice communications.

Transmitter of station 1XX
Credit: QST, April 1921.

Friday, March 27, 2015

Trilobite Detritus

The Craigleith area of Ontario is well known for its abundance of fossils. In 1992 I visited this locality on the southern shore of the Georgian Bay to search for them. There was a railway cut through the shale near Collingwood. The first slab of rock that I cracked open revealed a cluster of trilobite carapaces. They date to the late Ordovician which is about 445 million years ago.

Closeup of trilobite tail pieces.