Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: May 1, 2025
In the first part of this book we learned about spark-gap telegraph sets and how the oscillations they set up are damped and the waves they send out are periodic. In this and the next chapter we shall find out how vacuum tube telegraph transmitters are made and how they set up oscillations that are sustained and radiate waves that are continuous.
In no time the aerial was swinging above the windrow, and the lead-in wire had been brought back through the trees to the camp site. Here the instruments were connected and the wire coupled to them. The dry cells were next wired and the outfit was then ready. Lew sat down beside the spark-gap and pressed the key. Bright flashes leaped from point to point.
When the key was closed a series of sparks sprang across the spark-gap, and the waves were thus set up in the ether and carried the message to the receiving station.
This physicist showed that, if the electric waves are made to impinge on a flat wooden stand, on which are a series of resonators parallel to each other and uniformly arranged, these waves are hardly reflected save in the case where the resonators have the same period as the spark-gap.
A wireless system had also been erected on the roof of the building by the wireless enthusiasts of the troop and the helix, spark-gap and various coils and keys were also set up in the wire room. Headquarters immediately became popular with every member of the troop and always some one was to be found pottering about in the machine shop, building something that he was particularly interested in.
While Lew was writing down for him the wireless alphabet, Charley was showing him how to make the letters on the spark-gap. Before they turned in for the night, the ranger had learned to distinguish the difference between the sound of a dot and of a dash as the signals buzzed in the receiver. On the Trail of the Timber Thieves Very early the next morning the ranger was afoot.
Then he sat down beside his key, and while he watched the forester skin the wildcat, he kept his spark-gap snapping and cracking with the fat sparks from the new battery. He was calling Lew. He got no answer and flashed out the signal for the Wireless Patrol. Almost immediately Henry answered. His workshop was the headquarters of the Wireless Patrol. "Hello, Henry," rapped out Charley.
With a cry of joy, he put his finger on the key. It was almost the hour at which he was accustomed to exchange morning greetings with Mr. Morton. He pressed his key and a sharp flash resulted. Joyously he adjusted his spark-gap until he had a fine, fat stream of fire leaping between the posts. Then he fairly held his breath as he rapped out the ranger's call signal.
In the first part of this book we learned about spark-gap telegraph sets and how the oscillations they set up are damped and the waves they send out are periodic. In this and the next chapter we shall find out how vacuum tube telegraph transmitters are made and how they set up oscillations that are sustained and radiate waves that are continuous.
Differing from a spark-gap transmitter you cannot get any appreciable results with a low voltage battery current to start with. For a purely experimental vacuum tube telegraph transmitter you can use enough B batteries to operate it but the current strength of these drops so fact when they are in use, that they are not at all satisfactory for the work.
Word Of The Day
Others Looking