A hundred years ago, the January 1926 issue of theBritish publication Popular Wireless showed how to put together this “ultra” crystal set.  It was designed to  pull in the main BBC broadcast, as well as the then-new transmissions of station  5XX on 187.5 kHz.  That station broadcast from Daventry with high power (then 25 kW), with the idea of blanketing Britain with its signal.

The set was named “ultra” due to the fact that the honeycomb coils were designed such that the primary and secondary would always have their main portions directly next to one another, for maximum signal transfer.

Replica of the Jessup Wagon used by Carver as a mobile agricultural classroom.

We recently had the pleasure of visiting the George Washington Carver National Monument in Diamond, MO, Carver’s birthplace.  For the Route 66 fans, that’s not far from Joplin, MO.  Since Carver lived until 1943, we had no doubt that radio would play an important part of the exhibits.  And we were not disappointed, as one of the galleries contained the stylized antique radio shown above, which allowed visitors to listen to several radio broadcasts made by the scientist and inventor.  In addition, there were microphones and headphones which visiting students could use to create a similar radio interview.

You can find a sampling of broadcasts by Carver at the Iowa Public Radio website.  At this link, you can listen to the 1939 broadcast of “Strange As It Seems” about Carver, including an interview.

The monument also includes a classroom and laboratory.  The classroom is a non-specific period room, while the lab is modeled after Carver’s laboratory at the Tuskegee Institute.  The Monument is geared up for school field trips.  I noted that there were a number of rules written on the board in the lab, such as “four on the floor.”  One of the rules was the mortar and pestle must stay together, as I’m sure the mortar and pestle would otherwise make interesting toys for the students.

Carver died 83 years ago today, on January 5, 1943.

Seventy years ago, the January 1956 issue of Popular Electronics gave some suggestions on the kinds of things that electronics hobbyists could think about inventing.  The ideas came from the National Inventors Council, a governmental agency tasked with encouraging independent inventors to come up with ideas useful to the government and military.

Shown above is a 3D radar display.  The magazine noted that a “truly three- dimensional display would not only have wide application in military work, but might have wide commercial application in the development of a three -dimensional television system for home use.”  (We should note that Mr. Whoopee didn’t come up with his version until 1963.)

Some of the inventions described in the magazine did come to fruition.  For example, it mentions that the military is in need of a recording method which would cover a huge spectrum, up to 1000 MHz, but that current tape and wire recorders weren’t up to the task.  Today, it’s pretty commonplace for a software-defined receiver (SDR) to have recording capabilities, so that you can play back a huge chunk of spectrum.  Today, your computer has enough capability to do just that.

Similarly, the portable power sources that the military was looking for 70 years ago are probably in your pocket right now, as the battery in your phone meets most of those specifications.

The magazine mentioned that hams could probably come up with a “microwave oscillator, suitable for both continuous – wave and pulsed operation, with an output of 1 kw. or more.”  The idea shown at left did, indeed, come to fruition, and you probably have it installed on both your computer and phone, in the form of some kind of voice-recognition software.  So someone must have come up with that new approach mentioned in the caption.