1936 Two Tube Regen

1936JulPS21936JulPSEighty-five years ago, this gentleman was showing off the two-tube broadcast receiver that he constructed according to the plans shown in the July 1936 issue of Popular Science. The set’s main claim to fame was that it didn’t require expensive and heavy B batteries. The two-tube regenerative set ran off of just nine volts on the plates, plus an additional 1.5 volt battery to light the filaments of the type 30 and type 40 tube.

The simple circuit required only nine commercial parts–a transformer, an RF choke, two variable condensers, the tubes and sockets, and a switch. The “pancake” coils were easily wound at home.

The article noted that the layout of the circuit was quite critical, but over the course of a few months, the author pulled in more than 50 stations as far as 1500 miles away, with just a 12 foot indoor antenna and no ground.

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Safely Fixing Your TV: 1951

1951JulPMSeventy years ago this month, the July 1951 issue of Popular Mechanics gave some pointers on how to safely do some repairs to your television. The magazine noted that sets were much more complex than radios, but even inexperienced owners were often able to bring a radio set back to life by swapping tubes, and there was no reason that they couldn’t do the same thing with a television.

Of course, the first step was to make sure you knew which tube went in which socket, and the magazine provided sources for this information. The second issue was the high voltages, which could prove lethal, and the magazine noted how to make sure the capacitors were discharged before tackling the job.

If the picture tube had to be replaced, one important safety factor to keep in mind was that the tube could implode if dropped, sending chards of glass all over the room. As shown above, when doing this delicate job, it was important to wear gloves and safety goggles. To dispose of the old tube, it was put in the box in which the new one came. Then, it was taken to the back yard, and a crowbar was used to smash it to smithereens inside the box, so it didn’t risk implosion when the garbage man hauled it away.



1990 Grocery Prices

1990Jul13PghHere’s a snapshot of grocery prices in 1990, from the July 13, 1990, edition of the Pittsburgh Press.  You can click on the image to view a larger version.

According to this online inflation calculator, the dollar was worth just over two times as much then. One dollar in 1990 is the equivalent of $2.06 in 2021 dollars.

Let’s see how some of these prices compare. We’ve taken other looks at historical prices, but since these are “only” 30 years old, we can make apples-to-apples comparisons, since many of the same brand names are still around.

Here are some examples. We show the 1990 price, and the 2021 price at a local supermarket. If you want to take a look at the modern product, the links below are to Amazon.

Product 1990 Price 2021 Price Increase x
Baking potatoes, per pound 0.27 1.19 4.41
Vine ripe tomatoes, per pound 0.59 1.99 3.37
Watermelon, per pound 0.14 3.49 24.93
Whole chicken, per pound 0.79 1.99 2.52
New York Strip steak, per pound 4.19 20.62 4.92
frozen grape juice, 12 oz. 0.99 1.73 1.75
Yoplait Light Yogurt, 6 oz 0.50 0.67 1.34
Tropicana Orange Juice, 64 oz. 2.69 4.91 1.83
Muenster cheese, per pound 2.49 13.38 5.37
Banquet fried chicken, 28 oz. 1.99 8.44 4.24

In fairness, the 1990 prices were sale prices.  And some items, like the watermelon, might have been in season that day.  And you could probably shop around and find lower 2021 prices.  But the official inflation rate would see all of the old prices multiplied by 2.06.  So a few prices went down.  And in most of our earlier price comparisons, the prices went down.  But I would say that in the last 31 years, the real  inflation rate has been more than the “official” rate.

Some links on this site are affiliate links, meaning this site earns a small commission if you make a purchase after clicking on the link.

Diode Quiz

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Today’s quiz comes from the July 1961 issue of Popular Electronics. It’s tougher than it appears at first glance. The answers will appear tomorrow.



Proof of Time Travel

1921TalkingMachineWorldWe believe that the photo above conclusively establishes the existence of time travel. It appeared a hundred years ago this month in the July 1921 issue of Talking Machine World as an ad for Gennett Records from the Starr Piano Company of Richmond, Indiana.

DisasterGirlThe girl looks familiar, but you can’t quite place where you saw her.  We’re here to help you out.  She is Zoë Roth, “Disaster Girl” of internet meme fame.  The photo at left was taken in 2004, but she’s obviously the same girl in the picture above, taken 83 years earlier.

Fortunately, we’ve previously given advice to prepare for inadvertent time travel.

 



Vic Clark, W4KFC

1951JulBLSeventy years ago this month, the July 1951 issue of Boys’ Life carried a biography of Vic Clark, W4KFC.  Clark later went on to become president of the ARRL from 1982 until his death in 1983.  He was, however, already a well known ham in 1951.  His biggest claim to fame was taking first place in the 1948 November Sweepstakes.

According to the article, Clark’s interest in radio came when he happened to hear some hams on his family’s broadcast radio, and incident he said fired his interest.  He was licensed soon thereafter, as shown in the illustration above.  He went on to a career with the Civil Aviation Administration, later the Federal Aviation Administration.



1969 Grocery Prices

1969July8PghPressFor a snapshot of what groceries cost in 1969, this ad for Foodland appeared in the July 8, 1969 issue of the Pittsburgh Press.  If the prices look like a bargain, keep in mind that there has been a lot of inflation in more than half a century, and according to this inflation calculator, each dollar then was the equivalent of $7.34 in 2021 dollars. Or to put it another way, the federal minimum wage was $1.60, meaning that one hour’s work would earn a pound of bologna and six cans of vegetables.

A pound of roast beef was 49 cents, but adjusted for inflation, that’s $3.59, which still sounds like a bargain. Cans of tuna, on the other hand, were 25 cents, the equivalent of $1.84 in today’s money, which sounds rather pricey.

To view a full-size copy of the ad, click on it, and from most browsers, click again to enlarge.



1971 Portable TV’s

1971JulyPM1971JulyPM2Fifty years ago, this young woman was doing something one wouldn’t have dared doing in the first decades of television–she was watching it in the pool. In the 1950s or 60s, this would have been a highly reckless thing to do, since the high voltages involved could have lethal consequences if they came into contact with water. But by the 1970s, the art had progressed to the point where battery operated televisions were available. And the July 1971 issue of Popular Mechanics contained a review of the available offerings, penned by prolific electronics writer Len Buckwalter (who has appeared here many times previously).

Buckwalter starts by noting that the “portable” TV had been around for a long time, but it had an AC power cord and weighed up to 90 pounds. The only concession to portability was the handle slapped on top as an afterthought. But now, there were true portables hitting the market: Sets that ran off batteries and/or 12 volts, and weighing as little as 2 pounds, although the average was 15-20. There were even two color sets hitting the market, and prices started at under $100.

There were still power requirements, and most of the battery sets used rechargeable batteries. Those were good for only a couple of hundred recharge cycles, so he cautioned that for viewing outside, it would be wise to install a power outlet. Some of the very small sets used standard flashlight batteries, but most had a special rechargeable power pack. In some cases, it was built in, but in others, it was a separate unit, which made the set more compact when the battery was not necessary, such as in a car or boat.

A few of the samplings are shown at the left. At the top was Heathkit’s offering, which sold for $124.95, and could be put together in 15-20 hours. The detachable base of this set, the GR104A, contained the batteries.

Below that was the Symphonic 3-incher, with a built-in cassette recorder and AM-FM radio. Below that, for the well heeled, was Hitachi’s 12 inch color set, which sold for $369.95. Below that was a Panasonic 5-inch model whose screen folded away when not in use. It also contained an AM-FM radio.



Review of Accumed BNX N95 Masks: Made in the USA

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Bottom Line:  The AccuMed BNX N95 mask is a high quality protective mask, meets USA N95 standards, and is made in the USA.  Even if this pandemic is over, it’s worth keeping some on hand for the next public health emergency.  Update 12/26/21:  When this review was written, Amazon carried the 10 pack shown above.  At this time, only the 50 pack is available in white.   The other masks reviewed on this page are available in smaller quantities.  Update 12/29/21:  The 10 pack is available again in black at this link.

Quick Link

Preparing for Emergencies

I like to believe that I’m reasonably well prepared for emergencies, and the COVID-19 pandemic generally proved that I was prepared.  We never ran out of toilet paper, although early on, we did have to be careful with our limited supply, and at one point we were rationing coffee.  Curiously enough, the first thing we ran out of was lightbulbs, although we could have gotten by quite a bit longer by scrounging them from other rooms in the house.  Even when riots hit the area, we were fully stocked with all the necessities of life, other than having to use powdered milk for a few days.

In a few cases, we had to make substitutions.  We didn’t have very much hand sanitizer, but we solved that problem by washing our hands.  And even though sanitizing wipes were unavailable, bleach was readily available and we were able to use it for sanitizing items.

But there was one shortage that made me angry at myself:  In 2019, I could have walked into any hardware store to buy an N95 mask that was made in the USA.  And unlike most people, I actually knew that an N95 mask would be a useful thing to have around in a public health emergency.  But at the start of the pandemic, they were totally unavailable.  And early on in the pandemic, we were told that it was practically unpatriotic to wear a mask, especially an N95 mask, because the limited supply was earmarked for healthcare workers.

A few weeks later, the official advice flip flopped, and we were told that it was unpatriotic not to wear a mask.  But the N95 masks (in other words, the ones that were actually effective in preventing the spread of disease) were still off limits, since they were still reserved for healthcare workers.

During those early days of the pandemic, I rarely wore a mask, because I was rarely in a situation where I needed one.  I didn’t go into other buildings, period.  And I believed (and still do believe) that the risk outdoors was extremely small.  I did all of my shopping with curbside pickup or home delivery.  So I didn’t need a mask, because I wasn’t going into stores or other buildings.

The Need for a Good Mask

But eventually, there were unavoidable situations where I did need to go into buildings.  So after about three months, despite the official guidance to the contrary, I decided it was time for me to be selfish and buy an N95 mask.  Unfortunately, there were none to be had.  The best I could find at that time was a KN95 mask, and even those were hard to find.

“N95” means that a mask meets the U.S. Government’s NIOSH standards.  “KN95” means that the mask meets the standards of the Communist Chinese Government, and almost all of those masks were made in Communist China.  The irony wasn’t lost on me:  I was buying a Chinese Communist mask to protect myself against the Chinese Communist virus.  I wasn’t happy about it, but I only had myself to blame.  After all, in 2019, I could have walked into the hardware store and bought an American-made mask with the U.S. seal of approval.  I didn’t do so, and I was stuck having to rely on the Communist Chinese Seal of Approval.

The mask I bought was the one shown at the left, and it served me very well.  It was made in China, but it was imported by a reputable American company, AccuMed.  At the time, there were a lot of dubious products on the market.  I researched AccuMed and found that they were a medical supply company with an excellent reputation.  Frankly, their name on the product meant more to me than the certification from some Chinese lab.  The company was also in the process of gearing up to produce masks in the USA.  (The same mask, made in the USA, is now available.  Even though it is now made in the USA, it has the KN95 designation, probably because it uses ear loops instead of bands that go behind the head.)  Those masks served me very well for a couple of months.  On the occasions when I had to be inside the same building as other people, I was protected.

True to its promise, a few months later, AccuMed came out with a mask that was made in the USA, and I previously reviewed that mask, the duckbill-style A96 mask, similar to the one shown at left.  This mask was made in the USA, but it was sold as meeting the Chinese KN95 standard, because the American N95 certification was still pending.  It’s odd to have an American product that’s advertised as meeting the Chinese standard.  But the virus doesn’t care about the paperwork.  It was made in the USA by a reputable company, it seemed to form a tight seal, and I have no doubt that it provided protection.  And after I purchased it, the mask was approved, and now has the U.S. N95 seal of approval.

Edited to add (11/16/21):  The AccuMed A96 no longer appears to be available on Amazon, but this Kimberly Clark N95 mask, shown at left, appears to be identical.

This mask, like most N95 masks, was a bit more difficult to put on than the KN95 mask, because the elastic goes around the back of the head, and not just over the ears.  But even though it’s slightly harder to put on, it’s much more comfortable to wear, since it’s not constantly pulling on your ears.  If I had to wear a mask all day, this would be a huge advantage.


The New Made in USA N95 Mask

Fortunately, the time has now come when it’s once again possible to buy the thing that I should have bought in 2019:  An N95 mask made in the USA, the BNX N95 Mask NIOSH Certified MADE IN USA Particulate Respirator Protective Face Mask.  I recently received mine, and I’m glad to have it.Mask2

Like most other N95 masks, the straps go around the head, which makes it slightly more difficult to put on.  But the advantage is that it’s much more comfortable once you have it on.  It seems to form a good seal.  If I had to work for hours with this mask on, it would cause very little if any discomfort.

Both of the AccuMed N95 masks, the white one and the blue duckbill style one, are comfortable to wear, and both make a good seal.  For me, the white one is a little easier to put on, although the blue one seems to be easier to ensure a good seal once it’s on my face.  Either one, though, takes only seconds to put on.  One thing to keep in mind, though, is that the blue one seems to fit better on a smaller head.  My daughter had a hard time getting a good seal with the white mask, but it was much easier with the blue mask.  So if you are buying for a family, I would recommend getting both.

On the other hand, I now rarely have to wear a mask for more than a few minutes.  Therefore, I will probably continue to use  the AccuMed KN95 mask in those situations.  It seems to have a good seal, and if I’m just going into the store for a few minutes, it’s somewhat more convenient to put on.

accumed1Especially at the beginning of the pandemic, and probably still now, there were a lot of fake masks hitting the market, and it’s important to buy from a reputable source.  Fortunately, AccuMed/BNX is a real company, selling a real product, from a real bricks and mortar location in Houston, Texas, shown here.  You can probably find something cheaper at the dollar store, but it’s more important to buy something that will really protect you, rather than trying to save a few pennies.

Ongoing need for a mask

From my personal point of view, the pandemic ended on March 15, 2021.  On that date, the immunity from my second dose of the Moderna vaccine officially kicked in.  There’s still a possibility that I’ll be infected, but the risk of serious illness or death are practically nil.  The day after my immunity kicked in, I went from never going inside buildings unless absolutely necessary, to taking teaching jobs which put me in close contact with hundreds of kids.   (I secured an early dose of the vaccine as a teacher, and I felt it was my duty to resume teaching at the earliest possible moment.)  In my opinion, the need for a mask is now mostly gone.  Chances are, I will rarely wear the new N95 mask.  Because it was required this school year, I wore a mostly symbolic cloth mask while teaching.  With my vaccination, I didn’t feel the need to wear the N95 mask all day.  But if I had to work close to other people and was not yet vaccinated, I would certainly wear one of the N95 masks.

Even though I don’t believe it’s is necessary because of the vaccine, I have noticed that I didn’t get any colds or flu during the pandemic lockdown, because I wasn’t in a position to be infected.  On my first few trips back to Walmart after a long absence, I realized something:  There was a certain amount of truth to all of those “People of Walmart” memes.  Many of my fellow shoppers don’t look particularly healthy.  They might not be infections with COVID-19, but it’s likely that they’re infectious with something.  Wearing a mask for my own protection probably isn’t a bad idea, and since I have some of them, I’ll probably slip on the KN95 mask before going in there or similar environments.

Even though all of my masks are disposable, there’s no reason why they can’t be used many times.  I store mine in a paper bag labeled with the date.  I have links to official guidance on reuse of masks at my earlier review.  So when you order your masks, don’t forget to order a supply of brown paper bags.

At this point, I no longer have an immediate need for an N95 mask.  From my point of view, the pandemic is over, because I am vaccinated.  However, I didn’t need an N95 mask in 2019, and I’m still kicking myself for not going to the hardware store and buying one then.  It would have made the early months of the pandemic less stressful knowing that I had this supply if needed.

And the next pandemic might be worse, and during that pandemic, I might need to come into contact with other persons.  Even though it proved deadly to many, coronavirus was not as lethal as many anticipated.  But the next plague might be worse.  Having an N95 mask on hand for such an emergency is a low-cost way to make sure I’m prepared.  I hope I never have to use them, just like I hope I never have to use my potassium iodide.  But I feel a lot better knowing I have them.

During this pandemic, I never ran out of toilet paper.  And in the next pandemic, I won’t run out of N95 masks, because I bought some when they were still available.  I’m not making the same mistake I made in 2019.

I recommend all three of these masks.  The duckbill style mask in the middle seems to be slightly easier to get a good seal, although it’s slightly more difficult to put on in the first place.  If necessary, it would be comfortable enough to wear all day.  Of the three, it probably is the best choice for children.

The white mask on the left is slightly easier to put on, and would also be a good mask if needed for all day use.

The white mask on the right seems to be very good quality, although it does not have the U.S. N95 approval.  It is made in the USA, but has the Chinese KN95 approval.  The reason is probably the fact that it uses ear loops rather than head bands.  It is the easiest to put on, but the ear bands would be uncomfortable for all day use.  It’s the easiest to use if you have to go into a store for a few minutes.

Since they all have slightly different uses, I’m glad I have a supply of all three for the next pandemic.

 

 



The product was supplied at no charge by the manufacturer in exchange for an honest review. Some links on this page are affiliate links, meaning that this site earns a small commission if you make a purchase after clicking on the link.