Monthly Archives: September 2020

1950 Remote Speaker

1950SepPSThis woman is listening to the radio in her kitchen, but she’s doing it at the fraction of the cost of a new radio, thanks to the remote speaker described in the September 1950 issue of Popular Science.

The radio is playing in another room, up to 150 feet away. It’s an easy matter to run a speaker wire to another room, but this means that to adjust the volume, you need to go back to the radio. If you want to install the remote speaker in a noisy location, this can pose a problem.

The magazine provides a solution, as this is more than just a remote speaker. It actually contains a one-tube amplifier using the always useful 117N7GT tube, whose filament runs right off the line current. It’s hooked to the radio speaker terminals through a transformer, and the variable resistor at the input allows you to easily turn the volume of the speaker up or down, without having to adjust the radio.

The article points out that the idea would work equally well with an automatic phonograph with a stack of records.

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Getting Started in Ham Radio: 1960

1960SepEICoverIf you wanted to become a ham sixty years ago, the September 1970 issue of Electronics Illustrated had everything you needed to get started. It contained a 16-page special section with a number of articles by prolific author Len Buckwalter, K1ODH.

The section began with an introduction noting that barely a week went by when amateur radio didn’t hit the news. For example, it noted that hams had recently handled life and death message traffic after a Midwest tornado, and that hams on the U.S. East Coast and England had successfully worked each other by bouncing signals off an earth satellite. The magazine showed how to obtain a license and a station to join in this fascinating fraternity.

The first hurdle was the code, but the article pointed out that this was easy with records or tapes. To study for the written test, the magazine provided three pages of questions and answers of the material that would be on the exam, in the same format as the ARRL License Manual. Despite protestations of hams as to how hard the tests were back in the day, it’s clear that the 1960 Novice test could easily be passed by anyone of even modest intelligence.

According to the article, it was taking about six weeks for the license to arrive in the mail, and this time could be spent putting together the transmitter-receiver shown on the cover. The receiver is a one-tube regenerative receiver for 80 and 40 meters. It used a 6U8, half of which was a regenerative detector, and the other half an audio amplifier to drive the headphones. The transmitter used a 6V6 tube, and a power supply with transformer and 5Y3 rectifier was built right in, making the unit a complete station in one cabinet. Plug-in coils were used for both transmitting and receiving. The receiver was running all the time, with the antenna switched between transmit and receive. This made it easy to calibrate the receiver dial by using the crystal: The transmitter coil was removed to keep it from overloading the receiver. With the key down, the signal would be easy to find on the receiver dial. For an antenna, pointers for setting up either a longwire or dipole were given.

1960SepEIschematic



Making LOUD Crystal Sets: 1945

1945SepRadioCraftSeventy-five years ago this month, the September 1945 issue of Radio Craft carried these pointers by Joseph Dante Amorose for making a crystal set that did well. The author had been working on crystal sets for a quarter century, and he reports that this one was “LOUD–louder than any set I have tried in 25 years.” The article is not so much plans for a set, but a discussion of the attributes that made the set pull in the stations so well and so loudly.

While the article hit the newstands after peace had been won, the author noted the value of a crystal set in the time of war in which the article was written: “In this day of scarce electric radios, that should provide something of value; a radio set that stays constantly on the job is a real asset these days.”

He began by noting that the aerial should be at least 150 feet of 14 gauge wire, but 500 feet showed noticeable gain. The antenna led to a loading coil, which the author said must be used to add volume and improve both selectivity and range. He found that 60 turns of number 24 wire on a 3 inch bakelite form worked best.

The ganged condenser not only saved money, since they were cheaper than two separate units, but also added gain since there was coupling between the two capacitors. The article included much discussion of the tuning coils, and then turned to the detector. The author recommended using multiple detectors and using a switch. He noted that the loudest crystal was steel galena. But when there were a lot of local stations, then iron pyrite would provide more selectivity. And for experimentation, a fixed detector should be used. When swapping out components, any change in volume would be very apparent if the detector was not adjustable.

An extremely good ground was required. In the country, the best was the pipe running to the well. In the city, it would be the cold water pipe, and not the steam pipe. He notes that one ground works well, but five are better, and ten isn’t too many.

Finally, he stressed the importance of using the best possible headphones, with a high impedance, and from a good manufacturer. In short, he stressed that you should use the best you can afford.

1946JunPSIt appears that the author copyrighted a booklet entitled “How to build the Amorose loud speaking crystal radio,” and in June 1946, he ran this classified ad in Popular Science to sell some of his writings.

 



The USPS Delivers!

MailTest1We take unwarranted criticism of the U.S. Postal Service very seriously around here. As we reported previously, the Post Office stood ready to serve the nation even after a nuclear war, and during COVID-19 the men and women of the USPS have acted heroically to ensure that the mail goes through. Even when rioters burnt down two post offices in Minneapolis, the Postal Service quickly regrouped to make sure that its customers would continue to receive mail with minimal interruption.

Recently, for political reasons, the USPS has come under intense criticism, the gist of which being that they can’t do anything right. They were allegedly in the process of ripping out all of their sorting machines, and even removing mailboxes. The particular conspiracy theory was that without these sorting machines, they would be unable to deliver millions of ballots. This didn’t make much sense to us, since most ballots in a given locality would all be addressed to the same city or county election office, and wouldn’t require much sorting, by machine or otherwise.

And allegedly, the removal of mailboxes was to prevent voters from sending their ballots. The theory was that a voter would go to a spot where there used to be a mailbox, would see that the mailbox was gone, and then give up in despair. For the theory to work, the voter would have to be too dumb to look for another mailbox, take it to the nearest post office (where they would find a mailbox in the parking lot), give it to their friendly letter carrier, or just take it to the election office themselves. In short, as conspiracy theories go, it wasn’t very plausible, but a lot of people seemed to subscribe to it.

So as an experiment, I decided to test the United States Postal Service. I asked for volunteers on Facebook and NextDoor. I had them send me their address, and I mailed them an honest-to-goodness piece of snail mail. I had ten volunteers, and I asked them to inform me when they received the letter. I mailed the letters from three different locations. Some I mailed from a blue mailbox in front of a local strip mall (one of the boxes that was allegedly being torn out). Some I mailed from the drive-up mailbox in front of my local post office. And some I placed in my own mailbox, and the friendly letter carrier picked them up with the mail.

A small sampling of my letters is shown above. All ten were delivered in a timely fashion. Most of the transit times included a Sunday, but I included it. All ten of the letters were delivered in four days or less. Crosstown letters were delivered in either one or two days (the two day period included a Sunday). I tracked the average speed of each letter (measured by road miles from the center of the two ZIP codes). The slowest traveled an average speed of 0.16 miles per hour (845 feet per hour). That sounds slow, but keep in mind that I dropped it in a box in the afternoon, and there’s no way it could have arrived any earlier than the next day.

The fastest letter got from Minnesota to Maine at an average speed of 19.6 miles per hour. Remember, this included a Sunday, when it presumably didn’t travel at all. It was undoubtedly in multiple trucks during its trip. In my humble opinion, travelling at that speed for a mere 55 cents is an amazing bargain. Letters to Texas and Washington got similar excellent service. The full results are shown in the table below.

All of my letters were addressed by hand, and as my elementary school teachers would attest, my penmanship isn’t the greatest.  But the post office managed to sort them.  And all of the letters I saw had bar codes printed on them.  These would have been printed on the envelopes by an automatic sorting machine, and they are designed to be read by other automatic sorting machines.  These, of course, are the automatic sorting machines that the USPS allegedly ripped out and put on the scrap heap.  But somehow, my letters all made it through one or more of these allegedly non-existent machines.

In short, the criticism of the USPS is unfounded. As they have done throughout the pandemic, as they have done despite civil unrest, they continue to serve their country proudly.

If you’re wondering about the design on some of the envelopes, I copied the design from a 1944 patriotic cover. (You can see that cover and read more about it at this link.)  Just like they do today, during the war, the Post Office Department made sure that they mail went through. I’m sure there were detractors back then, but someone decided to print up some special envelopes to thank their letter carrier for heroic service.

We ought to do the same today.  If you haven’t done so recently, thank your letter carrier for his or her hard work.  And for the workers behind the scenes, you can invest 55 cents and mail them a thank you card.  Just address it to “Postmaster” and your city, state, and ZIP code.  I’m sure it will get pinned up to the employee bulletin board.  They’ve worked hard to serve you, and they deserve your thanks.

MailTest2



1940 Fish Pole Antenna

1940SepPSWhen this unnamed Hoosier took his girl fishing 80 years ago, we can’t help but believe that she was impressed by her date. Not only did he wear a tie for the occasion, but he demonstrated his ingenuity. He discovered that a steel fishing pole provided good reception when used as an antenna for his car. While the article doesn’t say, we have no doubt that he easily pulled in most of the Chicago stations in South Bend, Indiana, about 90 miles away. But when the couple arrived at the fishing hole, he removed the antenna and used it for its customary purpose as a fishing pole.

The photo appeared in the September 1940 issue of Popular Science, which doesn’t identify the couple, other than to note that he was a South Bend radio and fishing fan. We have no doubt that they had a fish dinner that night.



Postwar Radio Sales Begin

1945SepRadioRetailingSeventy-five years ago this month, the September 1945 issue of Radio Retailing was a thick one–175 pages. It was packed with ads from radio suppliers announcing that new radio would be rolling off the assembly lines for the first time in over three years. There was a pent up demand, and it was going to be a great time to be a radio dealer.

This editorial from that issue of the magazine tells all about the great day that was finally there. It was going to be a prosperous time, as Americans hit the showrooms for radios, appliances, and even television.

From most browsers, you can click on the image above to view it, and then click again for an enlarged version.



Laying Telephone Wire by Airplane

1945SepPMIt looks like Bell Labs was working on this idea toward the end of the war, and it probably wasn’t implemented, at least on a very large scale. But this ad from the September 1945 issue of Popular Mechanics sounds like a good idea for quickly laying lines for military field telephones. Instead of having men do the work on the ground, possibly through enemy territory, an airplane does the job, at a rate of 16 miles in 6 – 2/3 minutes. One end, with a weight and parachute, is dropped to the ground. Then, wire is spooled out continuously.