5 March 19

RTTY dates back to the mid 1800’s but was not transmitted over radio till 1922 by the US Navy between an aircraft and a ground station. Later that year RCA transmitted between a radio station in Chatham Massachusetts and a ship the R.M.S. Majestic… For more (Click Here)

The typical RTTY baud rate is 45.5 on amateur radio. For more history on Baudot (Click Here)

2 March 19

The USAA-CQ put on by CQ magazine is an ongoing world wide challenge for USA Counties. The rules and regulations can be found (Here). This challenge is ongoing and in the regulations you will find a link to the acceptable electronic logging program submissions. This contest is open to all Amateur Radio Operators. CQ Magazine has a few more Contests, (Click Here For The Calendar).

Source: CQ Magazine

28 Feb 19

Model J Echophone

The Echophone

Article and pictures are from The Perham Collections site.

The Radio Shop was founded by Arthur E. Bessey, Jr., a well-known amateur radio operator, sometime before May 1920. Bessey was already in business with his father in Sunnyvale, who had an innovative patent for incubators and brooders for poultry farmers. Bessey and his partners started their business in these poultry buildings, soon opening a sales location in downtown San Jose’s Bank of Italy building.

Patterning their parts after Colin Kennedy’s and claiming to have an official license from patent-holder Edwin Armstrong, they advertised a matching detector and two-step amplifier, and a three-circuit tuner. In 1922, as the radio boom hit the Bay Area, Bessey also started Sunnyvale’s first radio station, KJJ.

Initially, The Radio Shop built sets to order for other companies or distributors, then began to make simple sets under their own trade names, including the Echophone. Echophone eventually was sold to William J. Halligan, and became the basis for Hallicrafters.

The Perham Collection of Early Electronics includes two models of the Echophone:

24 Feb 19

Jamboree-on-the-Air, or JOTA, is the largest Scouting event in the world. It is held annually the third full weekend in October. JOTA uses amateur radio to link Scouts and hams around the world, around the nation, and in your own community. This jamboree requires no travel, other than to a nearby amateur radio operator’s ham shack. Many times you can find the hams will come to you by setting up a station at your Scout camporee, at the park down the block, or perhaps at a ham shack already set up at your council’s camp. … JOTA Website

Radio Merit Badge Requirements

Radio

23 Feb 19

The trembler coil was a device called a Ruhmkorff or induction coil, widely used in the 19th century.  It combines two magnetic devices on the same iron-cored solenoid. The first is a transformer, used to transform low voltage electricity to a high voltage, suitable for an engine’s spark plug. Two coils of wire are wound around an iron core. The primary winding carries the low voltage battery current, and the secondary winding generates the high voltage for the spark plug. Attached to the end of the coil is an interrupter or trembler, a magnetically operated switch or relay, which repeatedly breaks the primary current to create flux changes in the transformer needed to produce high voltage.

Source: Wikipedia

The black box on the far side with 4 white wires and 4 yellow wires is the trembler (or ignition box)

22 Feb 19

Spark transmitters and the crystal receivers used to receive them were simple enough that they were widely built by hobbyists. During the first decades of the 20th century this exciting new high tech hobby attracted a growing community of “radio amateurs”, many of them teenage boys, who used their homebuilt sets recreationally to contact distant amateurs and chat with them by Morse code, and relay messages. Low-power amateur transmitters (“squeak boxes”) were often built with  ignition coils from early automobiles such as the Ford Model T …

The Images below are from Hamfesters Radio Club Chicago Ill …. W9AA

Source: Wikipedia

14 Feb 19

First defined in ICAO publication “Doc 6100-COM/504/1” and in “ICAO Procedures for Air Navigation Services, Abbreviations and Codes (PANS-ABC)” [Doc8400-4] (4th edition 1989), the majority of the Q codes have slipped out of common use; for example today reports such as QAU (“I am about to jettison fuel”) and QAZ (“I am flying in a storm”) would be voice or computerized transmissions. But several remain part of the standard ICAO radiotelephony phraseology in aviation. These are also part of ACP131, which lists all ITU-R Q Codes, without grouping them by aeronautical/marine/general use.

For more about the “Q” codes “Click here Wikipedia

13 Feb 19

Thomas Edison patented Electromagnetic Induction, he called it “Grasshopper Telegraphy”. Which allowed telegraphic signals to jump the short distance between a running train and telegraph wires running parallel to the tracks. The system was successful technically but not economically. During the Great Blizzard of 1888, this system was used to send and receive wireless messages from trains buried in snow drifts. The disabled trains were able to maintain communications via their Edison induction wireless telegraph systems, perhaps the first successful use of wireless telegraphy to send distress calls. Edison would also help to patent a ship-to-shore communication system based on electrostatic induction. This is about all that is written about this but for more info and history “Click Here for Wikipedia“.

12 Feb 19

Examples of dielectric media are glass, air, paper, plastic, ceramic, and even a semiconductordepletion region chemically identical to the conductors. From Coulomb’s law a charge on one conductor will exert a force on the charge carriers within the other conductor, attracting opposite polarity charge and repelling like polarity charges, thus an opposite polarity charge will be induced on the surface of the other conductor. The conductors thus hold equal and opposite charges on their facing surfaces, and the dielectric develops an electric field.

A simple demonstration capacitor made of two parallel metal plates, using an air gap as the dielectric.

Source: Wikipedia