Bradshaw Lupton Jr, K1TE
A 1910 book about wireless telephone provides a fascinating look into radio’s early history.
Early on a steamy Sunday morning in August my eagle-eyed spouse, Paula, N1EOG, spotted a yellow pamphlet titled The Wireless Telephone sitting on a dealer’s dollar table at the Grafton, Massachusetts flea market. I was trying to be good and not spend the buck, but the cover drew me in (see Figure 1).
I fanned through the pages amazed at the simplicity in the ancient diagrams. This 1910 book detailed the birth of the “wireless telephone,” with the 25 year old author, Hugo Gernsback (see Figure 2), predicting the widespread proliferation of battery powered radiotelephones by 1920. Gernsback was based in New York City where he wrote, edited and otherwise documented the experiments of the early 20th century. He corresponded with the European radio experts and imported both the knowledge and the parts for the most exciting technologies of the early 1900s. He was a brilliant entrepreneur of what would become radio technology at a time before ham radio existed.
The first illustration in the book captured my imagination. Even though the radiotelephone it showed was just inductive and only transmitted 50 feet, I thought it was awesome that the receiver and transmitter combined used only eight parts (see Figure 3). In keeping with this simple design there followed instructions for a wooden lathing and 5 foot coil “antenna” (see Figure 4). While the method worked through 50 feet of wood, walls and stone, Gernsback noted “the coils must be aligned facing each other as it works poorly otherwise.”
Real Ground Wave
If 50 feet wasn’t DX enough for you, instructions followed for an earthen “closed circuit” telephone with only three parts. As you can see in Figures 5 and 6, it consisted of a pair of metal plates buried in the ground to which a modulated current was applied. These parts were available right there at the Grafton market in the form of an old telephone and a bunch of batteries. From these you could assemble a working wireless telephone! Gernsback used buried plates of zinc and copper, with an electrolyte of zinc chloride solution around each. He reached an amazing distance of 3 miles with the two plates 300 yards apart.
I have to admit, that while the cover hooked me, the working spark gap radiotelephone using only five parts was nearly incomprehensible (see Figure 7). I thought of the cell phone in my pocket with its umpteen million transistors and a $70 per month data plan.
The pamphlet further described the first Audion tube (see Figure 8), with its filament, grid and “wing” (plate). He talked about how the early tube systems started out very sensitive, but rapidly deteriorated. One probably had to mail away (to Gernsback) for replacement parts unless one could build and evacuate a tube in the basement. Included was a schematic of a radiotelephone receiver (see Figure 9). I noted that the diagram has the high voltage battery across the headphones — very, very scary.
Ever the businessman, Hugo Gernsback provided catalogs, parts and technology out of his Electro Importing Company (see Figure 10) in New York City. Gernsback was the visionary entrepreneur, experimenter, editor and thinker. I bought the book for a buck based on its cover, then fell in love with this fascinating look at radio’s first baby steps.
The back cover advertises his May 1909 Modern Electrics publication with the feature story “Signaling to Mars.” Now that’s one I want to read! If you have it or spot it, please drop me a line.
My spouse and I will continue to comb the Grafton flea market for more inexpensive and exciting published treasures.
Photos by the author unless otherwise indicated.
Bradshaw Lupton, K1TE, an ARRL® member, has been a ham since 1968. He has worked as a chemistry and physics teacher, a communications software engineer and currently is an instructional designer. Bradshaw has republished the 1910 public domain book The Wireless Telephone by Hugo Gernsback. It is available as an eBook for Kindle, Nook and iPad and also in hard copy from Amazon.com. Bradshaw can be reached via email@example.com.