A Review of the Uniden BC72XLT Handheld Programmable Scanner Radio

For the record, I do not own the featured image. I downloaded it from Radio Reference.

I have been listening to scanner radios since September of 2002, when I was fifteen going on sixteen.

In those days, I wanted to listen to police traffic, because I was a rebellious teenager and I felt very empowered when I did so.

At the age of twenty-two, I was seeing a new psychiatrist and she advised me that I shouldn’t listen to police traffic because it was too stimulating.

By that time, I was interested in listening to other stuff.

Since 2003 or so, I’ve been listening to retail, security and janitorial frequencies.

In 2011, I began listening to railroad traffic and was actually taught by others to understand what was being said.

Also 2011 was when I became a full blown foamer.

I say full blown because, since infancy I had harbored an interest in trains, but in late 2011 at the age of twenty-four going on twenty-five, I finally had the time to dedicate to my railroad hobby.

In 2015, after learning that railroads will eventually go to Nexedge, I was inspired by a dream in 2015 to start listening to marine traffic

I had been through several different scanners which I used specifically for my railroad and later my marine hobbies:
From December of 2011 until March of 2014; I used a Radio Shack Pro-404, it died on me in July of 2014, but always had receiver issues.
From March of 2014 until August of 2016; I used a Uniden BC75XLT, it worked great until the display failed-more on that in a bit.
From August of 2016 until October of 2018 and February of 2019 to present; I used a Uniden BC72XLT, which this piece will be a review of.

In August of 2016, the display on my Uniden BC75XLT had begun to malfunction. I was strapped for cash at the time and couldn’t afford a new one, so I looked on eBay and found a gently used Uniden BC72XLT for around $50. I purchased it and it came in the mail a few days later.

It was definitely a downgrade from the previous Uniden I had purchased.

For example:

It could only hold 100 memory channels whereas the BC75XLT could hold 300 channels.

It wasn’t narrowband capable like the BC75XLT.

It did not have a dedicated railroad search function.

It couldn’t be charged with USB.

Despite all of this, I find it was built more ruggedly and it was slightly more compact-excellent for when foaming or gongoozling on foot.

While it doesn’t have a dedicated railroad search, it does have dedicated service searches for conventional police, fire/medical, civilian aircraft, 10m/6m/2m/70cm FM amateur radio, VHF marine and weather radio.

This scanner can accept most frequencies between the ranges of 25-54 MHz, 108-174 MHz and 406-512 MHz.

It also has ten custom searches that can be programmed to search between those aforementioned bands.

There is a Uniden Close Call™ RF Capture Technology, which allows the user to detect nearby frequencies in use. This is especially useful for listening to retail or janitorial frequencies.

There is an orange backlit display for reading in low light conditions.

It has a generous runtime on 2 AA batteries.

From 2016 onward I had taken this scanner on just about every railfanning trip I’d been on and it pulls the signals in nicely and it does so even with just the stock antenna. The speaker has decent, crisp audio reproduction.

This scanner has assisted me watching trains in places like Raceland, Louisiana, (almost daily from August 2016 to January 2018), Des Allemands, Louisiana (every Sunday from August 2016 to January 2018), Schriever, Louisiana, (frequently between 2016 and 2018), Lafayette, Louisiana, (October 2016, January 2017, Ferbruary 2017, January 2018, February 2018, March 2018) Lake Charles, Louisiana, (February 2017, February 2018), Livonia, Louisiana, (December 2016), Plaquemine, Louisiana, (April 2016, December 2016, April 2018), Alexandria, Louisiana, (October 2016, January 2017, January 2018, April 2018), Oakdale, Louisiana, (October 2016), Meridian, Mississippi, (November 2016, November 2017), Baton Rouge, (April 2016, December 2016, April 2018), New Orleans (multiple times), Dallas (January 2017 and 2018), Shreveport (January 2017 and 2018), Little Rock (August 2018), Beaumount (February 2018), and Houston (February 2017.)

As for marine listening, this scanner has helped me in places like Houma, Louisiana, Amelia, Louisiana, Morgan City, Louisiana, Bourg, Louisiana, Bayou Blue, Louisiana, Lockport, Louisiana, Larose, Louisiana, Plaquemine, Louisiana, Tallulah, Louisiana, New Orleans, Baton Rouge, Baytown, Vicksburg.

Most of the fire dispatch voice pagers are still in analog FM and I do have their frequencies stored in this scanner.

Usually, I have it in a special slot of the console of my Buick Century and it keeps me informed and entertained.

So, even though it is 2019, there is still a good bit of stuff to hear on a budget friendly, entry level scanner.

In October of 2018, I had sold mine in order to have some extra spending cash.

However in February of 2019, I had ordered another one for about $60. Iinitially, I wanted it because I had planned to take it with me whilst fishing. However, I hadn’t been able to go fishing like I wanted to, but it is still frequently carried by me.

In fact, it is sitting on my computer stand in front of me as I am typing this review.

Even though narrowbanding to 6.25 KHz steps was mandated for 2018, many radio users are still using 15 KHz or 25 KHz steps in FM mode, including the railroads in 2019. They come in loud and clear in most cases. As for marine traffic, they will still be in 25 KHz steps for years maybe even decades to come, since VHF Marine is internationally implemented and regulated. This means that for listening to VHF Marine, this scanner is perfect and will be for a good while.

This scanner came on the market in 2004 and I believe was sold brand new until about 2011 or 2012. In the mid to late 2000s decade, this scanner was common among volunteer firefighters as a cheaper alternative to a voice pager. It was usually clipped to their belts next to the badge and a red Mini Maglite in its Nylon holster. It is now quite common on eBay, usually still in good condition.

I really enjoy this scanner, even though it was never top of the line.

I do give it a 4.85 out of 5 stars because it didn’t come with a dedicated railroad search and it didn’t cover 800 MHz, but other than that it is an awesome scanner radio.

This therefore concludes my review of the Uniden BC72XLT…

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A Review of the Realistic (Radio Shack®) Pro-32 Handheld Programmable Scanner Radio

I am a very sentimental person.

I also frequently think about what technology was like around the time I came into this world (especially radio and computer technology.)

Because of that, for years, I had wanted to own a Realistic (Radio Shack®) Pro-32 scanner.

Why?

Because it was put on the market in 1987, the same year I was born.

In 1987 this was Radio Shack’s premium handheld scanner. It retailed for $299.99 (which would be the equivalent of $674.84 in 2019 Dollars.) I bought mine second hand but in very good condition with the original box and paper work for $25 even (more on that in a bit.)

The Pro-32 runs on 6 AA Alkaline or Rechargeable (NiCad/NiMH) batteries. It also uses three watch batteries to power what was a vast memory (200 Bank+10 Monitor Channels) in 1987. The Frequency ranges it covers are:
30-54 MHz FM
108-136 MHz AM
138-174 MHz FM
AND
380-512 MHz FM

This scanner must have been a failure, because it was only featured in the Radio Shack Catalogs from 1987 to 1988.

In 1989, a significantly more sophisticated model was put on the market, the Pro-34. This better scanner also ran on 6 AA batteries, but did not require watch batteries for the memory. In addition to what the Pro-32 received, the Pro-34 had more frequency ranges:
806-823 MHz FM
857-868 MHz FM
AND
896-906 MHz FM

Many police, fire and EMS services as well as some bigger businesses would begin to migrate to 800 MHz in the 1990s.

The Pro-34 costed slightly more at $329.99 ($680.07 in 2019 Dollars)

What I find amusing though, is the Pro-32 seems to be the direct ancestor of several entry level scanner radios such as:

The Radio Shack Pro-79, which came out 15 years later in 2002 and is more power efficient (runs on 4 AA batteries instead of 6 and the memory is flash based instead of requiring those watch batteries) and costed $99.99 ($142.04 in 2019 Dollars.)

The Radio Shack Pro-82, which came out 16 years later in 2003 and has the features of the Pro-79 in addition to push button dedicated searches for certain radio services and costed between $79.99-$99.99 ($111.09-$138.87 in 2019 Dollars.)

The Radio Shack Pro-404, which came out 22 years later in 2009 has all the features of the Pro-82 in addition to a Signal Stalker/Spectrum Sweeper and PC programmable features and also costed $79.99-$99.99 ($95.28-$119.10 in 2019 Dollars.)

The Radio Shack Pro 649 which came out about 27 years later in 2014 and is almost a younger clone of the Pro-404, but can tune in more narrow frequency steps on certain bands and costed $99.99 ($107.94 in 2019 Dollars.)

The closest modern equivalent to it is the Whistler WS-1010, which came out 31 years or so in 2018 or so and has all the features of the Pro 649 but double the memory and costs between $79.99-$119.99 ($81.40-$122.11 in 2019 Dollars.)

I had checked on eBay quite a few times trying to buy this scanner, but there was always a problem purchasing it.

A few weeks ago, I had tried for the final time, when my transaction didn’t go through. Within seconds of the failed transaction, The Good Lord Himself told me stop and wait because I would be purchasing one at Ham Vention 2019 in Ohio.

I’m beginning to learn to obey Him and this time, I did just that.

And do you, the reader, know what?

The Pro-32 scanner I bought a Ham Vention was in much better condition and cheaper than any of the ones selling on eBay!

Any Christian (but only a Christian) is a child of the One True God. And God is a passionate loving Father who wants only the best for His children. This is a very small but still valid example of that.

By the way, this particular scanner is not very common. Case in point: It is vintage and it wasn’t in production very long. That means there probably aren’t too many in existence anymore. It would have taken basically an act of God for one to be available at the flea market, for me to see it there because the flea market is the size of a horse track and covered entirely with vendors and for no one else to purchase it. So the fact that God Himself told me I would be purchasing one at the Ham Vention flea market, strengthens my faith in Him and my walk with Him and it should be good testimony for believers and non believers alike!

I was planning to go to Ham Vention to purchase gently used flashlights and calculators in the flea market anyway, like I did last year.

I am indeed a ham and in fact, I do hold a General Class license.

Those of you whom were forwarded to my blog from Q R Zed already know this, but I don’t like to give out my call sign.

I’m not too active on the radio, because of where I currently live.

My lease forbids any sort of transmitting antennas and neither do I want to interfere with any of my neighbors’ electronics, because I tend to enjoy peace and detest drama.

So for that reason, I basically stay on 2 Meters and 440 with low power portable radios and usually only during emergencies.

I do all my HF, high powered long antenna activities at a friend’s house with his equipment.

So why besides it being as old as me would I want a Radio Shack Pro-32?

I mean, compared to the modern scanners: It is bulky as a brick in size and weight. It is power hungry as a starving pit bull in a butcher. It is slower than molasses in the dead of winter when it comes to scan and search speed. It is analog only which makes it obsolete, at least partially. And the coverage is limited.

Yes, that is all very true.

…BUT…

I find that for what I listen to most which is railroad and marine traffic, older scanners are far more sensitive than their modern counterparts. They clearly pull in signals from farther away that most modern scanners cannot even detect. Japanese electronics, which this particular scanner was made in Japan, seem to overwhelmingly outperform their Chinese and Vietnamese made descendants in ways where performance truly counts.

I interpreted the date code (5A7) to mean this particular unit was made in May of 1987. That means it was made thirty two years ago this month (the same month I bought it)!

What amuses and amazes me the most is that the model number is 32, I am 32 (at the time of writing this) and it is also 32! God definitely has His hand in this!

This concludes my review on the Radio Shack Pro-32.

I would like to thank and cite Radio Shack Catalogs for the picture (which I do not own) and the technical details.

I hope you the reader have been informed and entertained by this piece. Thank you for taking the time of reading and may God richly bless you!

Back to “Product Reviews”

About Television

This piece is about television: Analog…Digital…Cable…Broadcast…

I watch broadcast television.

When I say that, I mean “free” television that is received over the air with an antenna.

I don’t subscribe to any cable, satellite or Internet Protocol television at all.

Many other Millenials like me also do not subscribe to any pay television.

BUT, initially, I did it for different reasons than my fellow Millenials.

However, many of my fellow Millenials do subscribe to one or more streaming services, I don’t.

I am a total cord cutter and my only data traffic comes in and out on my cell phone.

Growing up, my parents always subscribed to cable.

They are indeed Baby Boomers and that generation almost as a whole fervently believes in subscribing to cable.

I think this is because, when they were growing up, the only people who had “clear” television reception were the city dwellers and everyone else had frequent reception issues. Not only that, there were maybe three main channels in a given market when they were growing up, whereas cable offers dozens to hundreds of channels. Cable was also much cheaper in the early days. I remember both my parents and grandparents saying how cable television was $8/month when they began subscribing.

However, myself and maybe other Millenials have noticed that since about the late 2000s cable television has skyrocketed in cost but plummeted in quality programming-change my (our) mind(s)!

I would dare say that it is not even worth eight 2019 dollars a month unless one lives totally out of any broadcast reception range (like maybe Texas, between San Antonio and El Paso or other extremely rural areas.)

When the Baby Boomers were much younger adults in the 1980s and 1990s, cable was wonderful, I’ll admit it and I’ll admit it until the cows come home. I was a child back then, but I remember how cable used to be very good. Nickelodeon had awesome cartoons and sketch comedies. VH1 and MTV actually played music videos! Arts and Entertainment, The History Channel and the Discovery Channel didn’t show constant reruns, but actually had very original and equally educational shows! TBS and TNT and USA Network had much more diverse and sometimes original programming unlike now where they mostly air reruns of shows that are already on broadcast television for free! And get this: CNN actually reported credible news without so much biased commentary!

I first “cut the cable” in the Summer of 2003, when I was sixteen and a half.

I finally had my own television, a 1992 Zenith Sentry 2 and I wanted to experiment with it.

This means that my initial reason for cutting cable was strictly experimental.

So I purchased a set of rabbit ears and a loop and connected them to that aforementioned television.

I would spend hours scanning the channels and constantly repositioning the antennas to see which stations I could receive.

At the time, I lived about sixty miles from Baton Rouge, fifty miles from New Orleans, and maybe eight miles from Houma, the three closest cities with television stations.

The rest of my family thought I was crazy.

My classmates that found out also thought I was crazy.

Let’s just say I was a cord cutter well before doing so was cool.

I guess that makes me at least partially a hipster.

I may sometimes wear my newsboy hat, but I refuse to grow a beard, so there.

This went on from 2003 to about 2006 and was basically before the June 12, 2009, FCC Digital Upgrade Mandate.

I will say that when comparing analog and digital broadcast television, both have some advantages as well as disadvantages.

Since the television I had was only an analog model and I didn’t yet have a converter box, I was only able to watch analog television.

However, analog television signals were able to travel further and could be received with lower quality antennas than their modern digital counterparts. Also, an analog television signal could still be intelligibly received whilst the receiver was in motion and even mobile (like in a car!)

All I had were rabbit ears and a loop, but I could catch both of the then VHF High New Orleans stations WYES-12 (didn’t watch much on it, but it had the clearest picture of all) and WVUE-8 (watched The Simpsons every Sunday night on there) almost perfectly. Most of the UHF New Orleans stations WNOL-38 (watched The Simpsons every weeknight on it), WHNO-20 (watched some preachers on there), WPXL-49 easily. The other UHF New Orleans-area stations WUPL-54, WGNO-26, WLAE-32 were hit and miss. The two VHF Low Band stations in New Orleans WWL-4 (despite being one of the most powerful television stations in the country) and WDSU-6 were difficult to catch, and had lots of static on my then configuration but would come in every now and then (and WDSU-6 had beautiful color when it did come in properly, it was always fun to watch Golf or Racing on there.) I could also catch the VHF High Band station out of Baton Rouge WAFB-9 all the time, (in fact when I wasn’t in school or working, I would watch As the World Turns on there.) The VHF Low Band station in Baton Rouge, WBRZ-2 would come in every now and then but always had lots of static. As for the UHF Baton Rouge stations, I could catch WVLA-33 most of the time and every now and then could catch WGMB-44 (would also watch The Simpsons on there when I could), which wasn’t even on my parents’ cable service. Sometimes the picture was almost clear, most of the time the picture was overall intelligible, but with some snow and white noise. These results were pretty much acceptable considering the antenna was an indoor model maybe six feet up and up to sixty miles away from the stations. Sometimes various forms of radio skip would occur and I would catch television stations from other states! That was always interesting and of course, caught my undivided attention. KFOL-30 (HTV-10) out of Houma was almost always guaranteed to come in but sometimes had a least a little white noise and snow in the signal.

I will say that it is virtually impossible in that location with that antenna setup to receive most of those stations since they switched to digital mode.

In December 2007, my then girlfriend, now ex-wife and I purchased our first Digital Ready television. It was a 24 inch Dynex CRT we purchased from Best Buy and was a Christmas gift to each other. Later on that day, I hooked up my rabbit ears and a loop to it excited to see what I could catch. We were living in her parents’ trailer in Raceland, Louisiana, which adversely affect television reception with that setup. However, I was only able to get WWL-36 (virtual channel 4.1) though sometimes it would come in clearly and beautifully but other times it would freeze up and fade out. One of the first things I remember catching on there was the “Happy Holidays” commercial for the New Orleans Public Belt Railroad. We also watched the CBS Evening News where Democratic presidential candidate Bill Richardson was being interviewed. Later that night I went to Wal Mart and purchased a set of rabbit ears and a loop with a built-in amplifier. This only made a marginal difference. For almost a year, we watched broadcast television with hit and miss results, then in the Summer of 2008, my now ex-wife but then girlfriend began subscribing to cable, which also meant home internet and phone. Also in the Summer of 2008, I applied for the coupons for a digital converter box. When they came in, I went to Wal Mart, purchased one and installed it on my old Zenith at my parents’ house.

On June 12, 2009, all full-power American television stations shut off their analog signals and began broadcasting strictly in digital.

Fast forward to the Spring of 2016. My then wife, now ex-wife and I were living in a second story apartment in Raceland, Louisiana. I had a man cave with that Dynex television and bought a cheap flat panel antenna for it. My then now ex-wife either watched Uverse in the bedroom or living room. I could catch a good bit of the New Orleans stations and the one Houma station since I was on the second floor and had a height advantage. I was never able to catch any of the Baton Rouge stations though and that irritated me, especially since they weren’t on our Uverse subscription either. At the time, however, I was more interested in listening to railroad communications on my scanners. In late 2017, my now ex-wife was badgering me how she wanted a ground floor apartment and since our neighbors below us moved out, we applied for and got it. This put a damper on my television and scanner reception. But even though my marriage was falling apart, I knew she had mobility issues and was even then was trying to appease her and her family. In early January of 2018, we mutually decided to cancel our Uverse television subscription and use Netflix and antennas but keep the Internet service in order to save money and pay down debt. Being on the bottom floor meant less television [and scanner] reception. However, I remember my ex watching Inside Edition and they were doing a piece on President Trump’s questionable diet. We could only catch WWL-36/(4.1) and KFOL-30. I wasn’t too happy about that, but I chalked it up to her wanting so badly to move downstairs. Then, I had found out some stuff she was doing behind my back coupled with years of mistreatment and I left her later that month also later that month and I applied for an apartment on the outskirts of Houma, Louisiana. I stayed with a friend until that apartment became available.

My ex wanted me to keep that old Dynex television, but I refused because I didn’t want to be reminded of her. God only knows where it is now.

I got my own apartment on May 1, 2018, and what was really a blessing is that I was offered a second-floor unit and gladly took it (a vertically higher position equals better television and scanner reception.)

Between leaving my ex and getting my own apartment, I purchased a 24 inch LG flat screen model and watched it at a friends house. it was hooked up to an attic antenna and I caught just about every station from New Orleans but none from Houma or Baton Rouge. This is because that attic antenna was a directional model and pointed at New Orleans. It also doubled as my computer monitor for the time being.

A few days after moving into my apartment, I set up my LG television. I knew I was not going to get cable and since my ex kept the other televisions and antennas we had, I went to The Ruble, I mean The Dollar General and purchased another flat antenna. I tried multiple several spots in my living room, until realizing that placing it in the window that faces the Gulf of Mexico, for whatever reasons pulls the stations in. I caught a few New Orleans stations and of course the one station in Houma. What is very strange though is I initially tried placing my antenna in the window that faces New Orleans but didn’t catch ANY stations doing so.

I used my phone for all of my Internet use, but many times I ended up with throttled data. In July of 2018, I had begun subscribing to Internet through Comcast. I had it until April of 2019 when I purchased a good enough mobile data plan to where I didn’t need home Internet anymore. Once again, I became a cord cutter!

Also a few days ago, my brother and his wife gave me their Samsung 43 inch Smart TV, since they upgraded. I put my LG in my bedroom and this Samsung television in my living room. However, I’ve noticed that while Samsung televisions do have very beautiful pictures, their RF tuning circuits aren’t that sensitive. LG televisions have superior RF tuning circuits and I think that has something to do with the fact that they merged with Zenith! Okay, that 1992 Zenith television also had a very good tuner and actually it was in my family until about 2010 or 2011! My maternal grandma also swore by Zenith televisions to the point where she referred to all remotes as “the Space Command.” I’ve also been told that her husband, my grandpa also swore by Zenith products, but he died 29 years before I was born. Anyway, that’s why I am so prejudiced in favor of Zenith and now LG! It was January of 2006 when I had found out that LG and Zenith merged. I was highly ticked off because, at the time, I had found that LG made junky phones, however, nowadays they make pretty decent phones and because of that Zenith engineering that they inherited, their televisions have the best tuners, hands down. I could give other detailed examples of this too, drop me a line and I will. So earlier this evening I purchased a better antenna for the Samsung and if need be, I will also get an amplifier. I cannot wait for it to come in. Currently, it only catches WWL-36/(4.1, 4.2, 4.3) and KFOL-30/(30.1, 30.3.) By the way, the LG television in my bedroom picks up a few New Orleans stations and of course the one station in Houma. I purchased the antenna for it at The Family Dollar and it is mounted high up on the wall that faces the Gulf of Mexico.

Now digital television does have its advantages over its analog ancestor. While the reception range is shortened, the picture quality is highly superior when the signal comes in properly. Also, the bandwidth required for one analog channel can fit six digital channels! Couple a good tuner and antenna system, most users can have a choice of channels that is almost on par with basic cable, but it costs nothing! Well, one does need a good antenna and that might also mean a tower, some coax, amplifiers, and a digital ready television or converter box, but the setup would pay for itself in one to three months!

As I stated on Facebook, I wish we could marry the signal strength and transmission range of analog television with the picture quality and channel capacity of digital television…It was that Facebook post I made earlier today that inspired me to write this piece!

But wouldn’t it be nice if ATSC 3.0 solves that exact issue, though?

If I were to live alone forever, I would probably be a cord cutter forever!

In fact, the only way I can see myself ever subscribing to cable again would be when/if my girlfriend and I marry and buy a house together. This would be so she can watch her Hallmark movies and listen to her Christian music on Music Choice. I’ll also admit that I’d be glad to watch and listen to that with her as those are one of the few rare modern perks of cable television. She treats me so well and because of that, I want her to be able to spoil her as much as possible and while I don’t currently believe in subscribing to cable, I would do it for her in a heartbeat. There are so many other things I want to do for her too as well. For the record though, we would have an antenna though for a backup for when the cable goes out.

Broadcast television has overall gotten better and cable has obviously gotten worse.

There need to be drastic changes in the cable and other subscription television industries as a whole, or more and more will get fed up and start hooking up antennas instead. They will lose too many customers and that will serve them right for charging too much for too little.

One of those changes I suggest is, if hospitals, hotels/motels, and even prisons can have cable without that freakin’ box (pardon my language but this really irritates me and therefore, unfortunately, warrants such crude language) and just plug the television directly into the cable wire, why can’t the average consumer do the same? I’ve been asking that question publically since 2016, but it has been on my mind much longer. Most of it is fueled by seeing my paternal grandma struggle to operate her cable box and her husband, my Paw Paw (God rest his soul) flat out give up on television because of the complexity of operating the cable box

I discovered broadcast television as an experiment but now rely on it daily for entertainment and information.

I much prefer broadcast over cable and I get mixed reactions for this preference.

I hope this piece has been informative and entertaining…

Notes on the Texas Instruments TI-36 Calculator

I have EDCed a Texas Instruments TI-36 X Pro (2011 version) either on my person, in my backpack or otherwise very near me since June of 2014. It is my favorite scientific calculator ever made!

For some time now, I had also been EDCing a composition book in my backpack and taking notes on subjects that interest me.

This page of notes pertains to the history of the TI-36 calculator and I will cite my main source as Wikipedia. I took these notes on October 14, 2018.

Without further ado, here are the notes:

These are details of the history and specifications of the TI-36.

The Texas Instruments TI-36 began in 1986 as an upgraded variant of the TI-35 Plus with Solar Cells a ten digit mantissa, two digit exponents, twelve-digit internal precision, base calculations (decimal, hexadecimal, octal and binary), complex values, statistics, the ability to convert the coordinates of polar and rectangular angles, an X-Y exchange, percentages, register-current stack exchange, factorial, permutation/combination, fifteen level parenthesis with six pending operation stacks, two operand registers (A,B) and one memory register.

The 1986 TI-35 Plus uses a Toshiba T7767.

The 1986 TI-36 Solar uses a Toshiba T7768 and features trigonometric functions, exponents, logarithms and intelligent order of operations.

They were upgraded in 1989.

The 1989 TI-35 Plus now uses a Toshiba T-7765 and now has a black shell.

The TI-36 Solar features smaller and more efficient solar cells. The Text, “ANYLITE SOLAR” replaces “SCIENTIFIC” on the bottom right of the face.

They were upgraded again in 1991 as the TI-35X or the TI-36X SOLAR and had a similar design of the TI-68, but lacking programming capability and the tilted screen.

There was also the addition of unit conversions such as: centimeters to inches, liters to US Gallons, kilograms to pounds, Celsius to Fahrenheit and grams to ounces, eight physical constants, a three-count register and two variable statistics with linear regression.

Base calculations now include Boolean logic (NOT, AND, OR, XOR, XNOR.)

Other new features included cube roots, fraction mode display and conversion of pure and mixed numbers.

The complex function was removed.

They have fifteen parenthesis stack level.

The 1991 TI-35X uses a Toshiba T6A58S and the 1991 TI-36 X Solar use a Toshiba T6A57.

They were mostly cosmetic upgrades in 1993, featuring redesigns of rubber like keys and a rounder case.

In 1996, the TI-36X Solar was upgraded with recolored labels, solid plastic keys. A bare processor was now attached to the motherboard.

The TI-35 was also discontinued.

In 1999 two variants of the TI-36 were released to the markets:

The TI-36 eco RS featuring a cabinet that was made from recycled plastics.

The TI-36 XII featured a two-line display, 11 5X7 cell characters, could store multiple expressions each holding eighty-eight characters, thirteen digit internal precision, five registers for memory, two registers for expressions, integer division, new unit conversions (meters to feet, meters to yards, kilometers to miles, litres-to UK Gallons and kilometers per hour to meters per second), eight more physical constants in addition to a Pi constant, two variable statistic regression models include natural logarithms, exponent, power, forty-two sample points or pairs can be stored, the binary base calculation was removed, the complex function was restored, supports conjugate, real/imaginary numbers, absolute value, integral calculation, random number generators, stacks were increased to twenty-three pending operations, eight pending values, a D-pad and a restyled cabinet.

2004 brought on another two upgrades:

The TI-36X SOLAR, which was a total cosmetic redesign on the 1996 model design. This new theme was based on the 2004 BA II Plus or the 2003 TI-1706SV.

There was also a slight redesign on the 1999 TI-36 XII, mostly different colored keys.

These were manufactured by Nam Tai Electronics.

In 2005, a talking version of the TI-36 known as the Orion was made to help the visually impaired.

2011 brought about the latest incarnation, the TI-36 X Pro.

Expression lengths were reduced to eight characters. Registers were increased to eight for memory, one for formula and can store three list formulas. Physical constants were increased by four to twenty, conversion sets increased to forty. Binary base calculations were restored.

A plethora of new functions were added:
Least common multiple, greatest common denominator, prime factors summation, product rounded value, integer part of a number, fractional part of a number, greatest integer smaller or equal to the number, minimum and maximum of the two numbers, Modulo calculus numeric derivative symmetric difference quotient method, two variable statistics, quadratic and cubic regressions, distribution functions, normal probability density function, mean=0 and sigma=1, function of x, probability between x boundaries, inverse cumulative normal distribution functions for a given area under the normal distribution curve with a user-specified mean and standard deviation, probability at x for the discrete binomial distribution with user-specified mean and standard deviation, probability at x for the discrete binomial distribution with user-specified trial number and probability of success per trial, cumulative probability at x for binomial distribution with specified trial number of success per trial, probability at y and y for Poisson distribution with the specified mean, statistics results min/max of x values 25/75 percentile, function table formula based generator, manual table Matrix three editable tables, preset 2X2 and 3X3 identity matrices, matrix arithmetic vector three editable tables, preset last matrix/vector result, vector arithmetic, dot product, cross product, polynomial solver 2nd/3rd degree solver, linear equation solver 2X2 and 3X3 solver, Base-N operations, Boolean operators, expression evaluation, complex numbers, polar coordinate entry, polar cartesian display mode angle for complex number.

In 2017 and continuing, the TI-36 X Pro is now made in The Philipines.

The TI-35 and TI-36 lines are the highest end models of Texas Instruments scientific calculators.

TI-36 Calculator History Table:
YEAR……..Model………Processor……..Country of Manufacture
1986……..TI-35 PLUS….Toshiba T7767….Italy
1986……..TI-36 SOLAR…Toshiba T7768….Taiwan ROC
1991……..”” “”………Toshiba T6A57….Italy
1996……..TI-36 X SOLAR.??……………Mainland China
1999……..TI-36 eco RS..??……………”” “”
1999……..TI-36 X II……??……………”” “”
2004……..”” “”………??……………”” “”
2004……..TI-36 X SOLAR.??……………”” “”
2011……..TI-36 X Pro…??……………Mainland China
2017……..”” “”………??……………The Philipines

Notes on Weather Radios

I first discovered Weather Radios in December of 2001 when I was 14 going on 15. That previous spring and summer I had begun to cultivate an interest in all forms of radio communications. As previously stated, I always had a fascination with weather. So, to me, a weather radio seemed to be a pretty cool device.

I wrote these notes on Weather Radios in the composition book I had been EDCing on October 3, 2018. The main source for these notes I have taken that I will cite is Wikipedia.

Without further ado, here are the notes:

A Weather Radio is a special radio receiver that is designed to receive the signals from government owned radio stations that broadcast weather observations continuously.

Routine reports are interrupted when a weather emergency arises.

Some non weather emergency information may be broadcast such as a natural disaster, civil emergency or terrorist attack.

Broadcasts occur on the VHF High Band.

Two varieties are sold: Home and Portable.

Portable models come with features such as crank power in addition to grid current and batteries for use in an emergency when the power is disrupted. Smaller portable/pocket models do not typically feature Specific Area Message Encoding, but allow outdoor enthusiasts to get weather information in a compact device.

Modern Home models have in addition to Specific Area Message Encoding, visual alert features such as text displays and multi-colored lights. They also have connections to add peripherals such as pillow shakers or bed shakers, strobe lights and loud sirens for people with sensory disabilities. There peripherals can be connected via the weather radio’s accessory port.

NAVTEX gives Global Weather alerts for ships at sea. It is a Low Frequency Teletex broadcast.

In the United States NOAA Weather Radio is a nationwide network of automated weather broadcast stations giving weather information from a nearby Nation Weather Service forecast office. A broadcast cycle lasts between three and eight minutes.

Specific Area Message Encoding activates radios based on the Federal Information Processing System codes and radios equipped with that said feature will only activate when the corresponding administrative division programmed in the radio has an emergency.

Weather Radio Channels and Frequencies:

Original Number…..Frequency…….Marine Number……New Number
WX01…………….162.550 MHz…..39B…………………….7
WX02…………….162.400 MHz…..36B…………………….1
WX03…………….162.475 MHz…..97B…………………….4
WX04…………….162.425 MHz…..96B…………………….2
WX05…………….162.450 MHz…..37B…………………….3
WX06…………….162.500 MHz…..38B…………………….5
WX07…………….162.525 MHz…..98B…………………….6
WX08…………….161.650 MHz…..21B…………………..N/A
WX09…………….161.775 MHz…..83B…………………..N/A
WX10…………….163.275 MHz…..113B…………………N/A

Notes on the Electronic Calculator

Since infancy, I have had a great fascination with calculators, in fact just about as much as with flashlights. This is because they were always around me growing up. Before my dad became a special education teacher, he was a bank executive so therefore he always had a calculator until his career change. My mom has taught high school math since 1980 and she has always EDCed a scientific calculator or two. I had EDCed a calculator on and off since the age of eight and then permanently since the age of twenty-five. Though both of my parents are teachers, I am not. I am more or less of an amateur tradesman, especially in the trades of electrical and computer repair. Because of this, I greatly realize the need to EDC a calculator, though not for the same reason as my parents. For a while, I have been also EDCing a composition book on which I take notes on subjects that I consider important to me. On October 2nd and 3rd of 2018, I did some research on electronic calculators and took notes into my composition book. I am transcribing these notes for others to read.

Without further ado, here are my notes on electronic calculators:

Wikipedia is the source I cite as that is where the bulk of this information comes from.

The first solid state electronic calculator was created in the early 1960s.

Pocket-sized models came avaailable in the 1970s after the first microprocessor, the Intel 4004 was invented.

By the end of the 1970s, basic calculators were affordable to most and became common in schools.

In 1986 ~41% of the world’s general purpose hardware capacity was represented by calculators. As of 2007, it is only 0.05%.

Processor Components:

The Scanning/Polling Unit scans the keypad waiting to receive an electrical signal when a key is pressed.

The X and Y registers are where numbers are temporarily stored during calculations. All numbers go into the X register first, the number in the X register is displayed.

The function for the calculation is stored in the Flag Register until the calculator needs it.

The Permanent or Read Only Memory or ROM is the instructions for built-in functions that are permanently stored and cannot be deleted.

The User or the Random Access Memory or RAM is where numbers can be stored by the user and contents can be changed or erased by the user.

The Arithmetic Logic Unit or ALU executes all arithmetic and logic instructions and produces results in binary code.

The Binary Decoder Unit converts the binary results into decimal numbers which are shown on the display unit.

The clock rate of the processor chip refers to the frequency of which the Central Processing Unit is running. It indicates the processor’s speed and is measured in clock cycles per second and expressed in the unit of Hertz. Basic calculations can vary between a few hundred Hertz to the KiloHertz range.

The first devices used to aid in arithmetic calculations were bones, pebbles, counting boards and the Abacus which was used in ancient Egypt and Sumeria before 2000 BC.

Computing tools started to arrive in the 17th Century with inventions such as the Geometric Military Compass, made by Galileo.

Logarithms and Napier’s bones were invented by Scottish mathematician John Napier of Merchiston (1550-April 4, 1617.)

The slide rule was invented by English and Welsh clergyman, mathematician and astronomer Edmund Gunter (1581-December 10, 1626.)

In 1642, the mechanical calculator was invented by German professor and minister Wilheim Schickard (April 22, 1592-October 24, 1635) several decades before the device invented by French mathematician, physicist and writer Blaise Paschal (June 19, 1623-August 19, 1662.) Schikard’s device used a well-thought set of mechanized multiplication tables to quicken the process of multiplication and division. Paschal’s calculator could add and subtract two numbers directly.

German polymath Gottfried Leibinz (July 1, 1646-November 14, 1716) spent four decades attempting to design a four operation mechanical calculator he called “The Step Reckoner. he was not successful but in the process, he invented “The Leibinz Wheel.”

At that point my medication kicked in and I went to bed, then resumed taking notes on October 3, 2018.

There were five other unsuccessful attempts to design a calculating clock in the 17th Century.

The first successful calculating clock was invented in the 18th Century by Marquess physicist, mathematician and antiquarian Giovanni Poleni (1683-November 1761.)

Assumed Italian inventor Luigi Torchi (1812-?) invented the first direct multiplication machine and the second key-driven machine in the world, following James White’s invention in 1822.

Real developments began during the Industrial Revolution of the 19th Century. This made large scale production of devices that could perform all four functions of arithmetic.

The Arithmometer was invented in 1820 and put into production in 1851. It became the first commercially sold unit and by 1890, 2,500 units had been sold. There were even clone units from Burkhardt, Germany, in 1878 and Layton, UK, in 1883.

In 1902, American James Dalton invented The Dalton Adding Machine with the first push-button interface.

In 1921, American Electrical Engineer Edith Clarke (February 10, 1883-October 29, 1959), the first female professor of Electrical Engineering at UTA invented the “Clarke Calculator” which was a simple graph-based calculator for solving line equations that involved hyperbolic functions. This device gave electrical engineers the ability to simply calculate inductance and capacitance in power transmission lines.

In 1948, Austrian engineer Curt Herzstark (July 26, 1902-October 27, 1988) invented the pocket portable calculator which was called the “Curta.”

Casio released the Model 14-A in 1957. It was the world’s first all-electric compact calculator.

In October of 1961, British Bell Punch/Sumlock Comptometer ANITA, which is an acronym for “A New Inspiration To Arithmetic/Accounting” was announced. It used cold cathode tubes and Dekatrons in its circuits in addition to 12 cold cathode Nixie tubes. There were two models displayed: the Mk VII was for Continental Europe and the MK VIII was for the UK and the rest of the world.

Tubes began to be phased out in 1963 when the American-made Friden EC-130 was built of an all transistor design. It featured a stack of four thirteen digit numbers and a five-inch cathode ray tube. It also introduced Reverse Polish Notation. This machine sold for $2,200.

In 1964 Sharp introduced the CS-10A. It weighed 25 kilograms or 55 pounds and cost 500,000 yen or $4,457.52.

Italian company Industria Machine Electroniche also introduced the IME-84 with several peripherals so several users could make use of it (but not simultaneously.)

Several manufacturers followed including Canon, Mathatronics, Olivetti, Toshiba, Smith Carona Marchant, and Wang. These calculators used Germanium as opposed to Silicon for their transistors. Displays were either Cathode Ray Tube or cold cathode Nixie tubes and filament lamps. Memory was either delayed line memory or magnetic core memory. However, the Toshiba “Toscal” BC-1411 possibly had an early form of Dynamic Random Access Memory.

In late 1965, the Olivetti Programma 101 was released. It could read and write stored programs on magnetic memory cards and display the results on its built-in printer. Memory was achieved with an acoustic delay line and could be partitioned between program steps, constants and data registers. It could be considered the first commercially made personal computer and won many industrial design awards.

Also in 1965 the Bulgarian made ELKA 6521 was released. The name is derived from a portmanteau of ELektronen KAlkulator. It weighed 8 kilograms or 18 pounds. It was the first calculator to feature a square root function. Later in 1965 the ELKA 25 with a built-in printer was introduced. The ELKA 101 was released in 1974 and was ELKA’s first pocket model. It featured Roman script (I guess as opposed to Slavic)since it was exported to Western Countries.

In 1967, the Monroe Epic was put on the market. It was a large printing desktop model with an attached floor standing logic tower. It could be programmed to carry out many computer-like functions. Unfortunately, the only branch instruction was an implied unconditional branch (GO TO) at the end of the operation stack, which returned the program to its starting instruction. Therefore it was impossible to include any conditional branch ie (IF-THEN-ELSE) logic.

During this time period, the absence of a conditional branch sometimes determined the difference between a programmable calculator and a computer.

Also in 1967, Texas Instruments American electrical engineer Jack Kilby (November 8, 1923-June 20, 2005) led the production of the first prototype of a handheld calculator, the “Cal Tech.” It could perform the four basic operations and printed the results on paper tape.

In 1970 a calculator could be produced with just a few low power chips and be powered by rechargeable batteries. Also in 1970, the first portable calculators appeared in Japan and were sold around the world. Models included the Sanyo ICC-0081 Mini Calculator, the Canon “Pocketronic” and the Sharp QT-8B “micro compet.”

Desiring to reduce power consumption, Sharp introduced the EL-8 which was also marketed as the Facit IIII. it was close to being a pocket model and weight 1.59 pounds or 721 grams, had a vacuum fluorescent display, rechargeable NiCad batteries and sold for $395.

In early 1971, the first “Calculator on a chip” the MK6010 was made by Mostek. Also in 1971, Pico Electronics and General Instrument introduced the chipset for the Monroe Royal Digital III calculator.

The Busicom LE-120A “HANDY” was the first truly pocket-sized calculator. It was the first to feature an LED display, first to use a single integrated circuit and the first to run on primary batteries. It measured 4.9 inches by 2.8 inches by 0.9 inches (124 millimeters by 71 millimeters by 23 millimeters.)

The DB800 was made in 1971 in Buje, Croatia, and was the first European made pocket calculator.

The Bowmar 901B was the first American made pocket-sized calculator which measured 5.2 inches by 3.0 inches by 1.5 inches (132 millimeters by 76 millimeters by 38 millimeters) and was put on the market in Autumn of 1971. It featured the four basic functions, a red LED display and sold for $240.

Then in 1972, the first slimline pocket calculator was released. It was the Sinclair Executive. Measuring 5.4 inches by 2.2 inches by 0.35 inches (137.2 millimeters by 55.9 millimeters by 8.9 millimeters), it sold for 79 Pounds.

The first pocket-sized Soviet-made calculator was the Elektronika B3-04 was developed in 1973 and put on the market in 1974.

In 1973, the Sinclair Cambridge was launched. It sold for 29.95 Pounds or $38.40. Because of their lower price, Sinclair units were popular but they were slower and sometimes produced inaccurate results with transcendental functions.

The first Soviet-made, pocket-sized scientific model B3-18 was completed by the end of 1975.

Texas Instruments introduced the SR-10 (SR stands for “Slide Rule.”) It was an algebraic entry-level pocket calculator using scientific notation and sold for $150. Afterward, the SR-11 was released and had a dedicated key for the Pi constant. The following year, the SR-50 was released and added the trigonometric and logarithmic functions. It was a competitor model to the Hewlett Packard HP-35.

In 1976, the Texas Instruments TI-30 was launched and descendants of it are still in production.

In 1978, Calculated Industries made special purpose calculators such as the “Loan Arranger” which was marketed to Real Estate professionals. In 1985 they launched the “Construction Master” which was marketed to the building trades.

Programmable calculators such as the Mathatronics and Casio AL-100 were very heavy and costly.

The Hewlett Packard HP-65 came out in 1974 and had a capacity of 100 instructions and could store and retrieve programs in a built-in magnetic card reader. The HP-25 introduced continuous memory which stored data and programs in a CMOS. The HP-41C was released in 1979 and could be expanded with Random Access Memory and Read Only Memory. It could also be connected to bar code readers, microcassette and floppy drives as well as printers and communication interfaces such as the RS-232, HP-IL, and HP-IB.

The ISKRA123 was Soviet-made, grid powered and released in the early 1970s. The Elektronika B3-21 was developed at the end of 1976 and put on the market in early 1977. Its successor, the B3-34 was widely used and hundreds of thousands of games and program were written for it. The Elektronika MK-52 was used in the Soviet Space Program.

The Hewlett Packard HP-28C was released in 1987 and was the first calculator capable of symbolic programming.

The Casio fx-7000G was released in 1985 as the world’s first graphing calculator.

In 1981, the Hewlett Packard 12-C was the first financial calculator…

Notes on the Barometer

I have been fascinated by the weather since early childhood.

I have also had a keen interest in sciences of all kinds, throughout my life though I am not very good at it. I mean I am so terrible at science that I don’t even hold an Associate’s Degree.

However, I do spend a good bit of my time engaged in independent learning.

In this page, I will post the transcript of notes I had taken in my composition book that detail information about Barometers.

Without further ado, here they are:

These notes were taken on October 1st and 2nd of 2018.

The main reference that I will cite is Wikipedia as that is where I got the bulk of this material from.

Notes on the barometer and its inventor(s).

Barometers are used in meteorology to measure atmospheric pressure.

Pressure tendency detects short term changes in weather.

Measuring air pressure within surface weather analysis is helpful in locating surface troughs, high-pressure systems and frontal boundaries.

The term “barometer is derived from ancient Greek words which literally translate into words that mean weight and meter/measure.

Evangelista Torricelli (October 15, 1608-October 25, 1647) an Italian physicist and mathematician are credited with inventing the barometer in 1643.

Italian astronomer and mathematician Gapardo Berti (1600-1643) may have also unintentionally created a water barometer sometime between 1640 and 1643.

French scientist and philosopher Rene` Descartes (March 31, 1596-February 11, 1650) described the design of an experiment to measure air pressure possibly as early as 1631 but no evidence is there to suggest that he actually built such an instrument.

On July 27, 1630, Italian mathematician, physicist and astronomer Giovanni Battista Baliania (1582-1666) wrote to Italian polymath Galileo Galilei (February 15, 1564-January 8, 1642) describing a failed experiment in which he made a siphon led over a hill ~21 meters high. Galileo replied explaining that the power of the vacuum held the water up but at a certain height the amount of water was simply too much and the vacuum could not hold anymore, like a cord that can only support so much weight. This was a restatement of “horror vacui” or “nature abhors a vacuum, a theory which dates back to ancient Greek philosopher and scientist, Aristotle (384-322 BC.) Galielo restated this theory as “resistenza del vacuo.”

These theories were published in Galileo’s “Discoursi” and they reached Rome in 1638.

Raffade Magiotti and Berti were excited by these ideas and sought another way to produce a vacuum besides a siphon.

Magiotti devised the experiment and Berti carried it out sometime between 1639 and 1641.

A simple model of this experiment consisted of filling a long tube with water plugged on both ends, then stood up in a water-filled basin. The bottom plug was removed and the water inside the tube flowed into the basin. However, only a portion of the water flowed out of the tube and the height of the water inside the tube stayed at an exact level, which happened to be 10.3 meters or 34 feet, the same height that Galileo and Baliani observed to be limited by the siphon.

The most important detail of this experiment was that lowering the water in the tube left a space above it in the tube with no immediate contact with air. This suggested the possibility of a vacuum existing in the space above the water.

Torricelli, a pupil, and friend of Galileo interpreted the results of this in a novel way. He proposed that it was the atmosphere and not the attracting force of the vacuum that held the water in the tube.

Followers of Aristotle and Galileo thought air to be weightless.

Torricelli questioned and challenged this belief and suggested that air indeed has weight and it was the weight of the air which pushed up and held the column of water.

Torricelli believed that the level of which the water stayed at in the tube (10.3 meters of 34 feet) was reflective of the air’s weight pushing on the water in the basin, thus limiting how much water can fall from the tube into the basin.

Torricelli viewed the barometer as a balance or measuring instrument instead of a device to merely build a vacuum.

Because pf Torricelli being the first to observe this, he is credited as being the inventor of the barometer.

Torricelli’s gossipy Italian neighbors spread rumors that he was engaging in sorcery and witchcraft. Torricelli thus decided to keep his experiments a secret to avoid being arrested by the Roman Catholic Church.

In order to be more covert, he needed a liquid denser than water, to which Galileo suggested he use Mercury. As a result, he only needed a tube that was 80 centimeters long as opposed to 10.5 meters.

*SIDE NOTE*: While I was initially taking these notes on that evening in early October 2018, I decided to take a few sips of Wild Cherry Pepsi in an attempt to temper the sting of depression which I frequently suffer. Soft drinks, while extremely addictive do indeed help me write better and they do help fight depression, at least for me. Wild Cherry Pepsi is my favorite soft drink.

Decreasing atmospheric pressure was initially postulated by French physicist Lucien Vidi (1805-April, 1866.) He later invented the barograph, a device which records the pressure readings of an aneroid barometer.

German writer and polymath Johan Wolfgang Von Goethe (August 28, 1749-March, 22 1832) invented a water driven barometer based on Torricelli’s principles. It is known as the weather ball barometer and is comprised of a glass container with a sealed body half-filled with water. The narrow spout is open to the atmosphere. When the pressure is lower than it was at the time the body was sealed, the level of water in the spout will rise above the water level in the body. When the pressure is higher, the water level in the spout will drop below the water level in the body. This device is known as a “weather glass” or a “Goethe Barometer.

Mercury Barometer:
A vertical glass tube closed at the top sitting in an open Mercury filled basin at the bottom. The Mercury’s weight creates a vacuum at the top known as a “Torricelli Vacuum.” The Mercury in the tube fluctuates until the weight of the Mercury column balances the force of the air pressure bearing down on the reservoir. Higher temperature levels around the instrument will reduce the density of the Mercury, thus the scale must be calibrated in such a way to compensate for this effect. The tube must be as long as the amount of Mercury in addition to the headspace as well as the maximum length of the column.

Torricelli observed slight changes each day in the height of Mercury in the tube and concluded that this was due to changing pressure in the atmosphere.

On December 5, 1660, German scientist, inventor and politician Otto von Guerricke (November 20, 1602-May 11, 1686) observed that the air pressure was unusually low and predicted a storm which struck the next day.

The Mercury barometer’s design made the expression of atmospheric pressure in inches of Mercury popular. The range is typically between 26.5 and 31.5 inches (670-800 millimeters) of Mercury.

One atmosphere is equivalent to 29.92 inches or 760 millimeters of Mercury.

On June 5, 2007, the governments of the European Union restricted the sale of Mercury, effectively ending the manufacture of new Mercury barometers in Europe.

An aneroid barometer uses a flexible metal box instead of any liquid to measure air pressure. It was invented in 1844 by Lucien Vidi. The box is known as an aneroid cell or capsule made from an alloy of Beryllium and Copper.

The evacuated capsules are many times several stacked together to add movement and are protected from collapsing by a strong spring. Any change in the surrounding air pressure causes the capsule to expand or contract.

This movement drives mechanical levers in such a way that their changes are amplified and displayed on the dial face of the instrument. Many models also feature a manually set needle to mark the current observation and compare with previous and future observations so a change can be seen.

Microelectromechanical systems (MEMS) barometers are extremely small ranging size between 1 and 100 micrometers. They are manufactured using photolithography or photochemical machining. These can be found in miniature weather stations, electronic barometers, and altimeters.

Certain smartphones such as the Samsung Galaxy Nexus, Samsung Galaxy S3 through S6, the Motorola Xoom, Apple iPhone 6 as well as higher end Casio and Timex watches have built-in barometers using MEMS technology.

Formulas:
Pressure in atmospheres Patm=p*g*h
Where p=density of Mercury=13,595 kg/meter cubed (sorry I don’t know how to do sub and superscript on here) g=graviation accelaration=9.807 meters per second squared, h=height.
1 torr=133.3 Pascals or 0.03937 inches of Mercury.

My personal commentary:
Most weather predictions for civilians are obtained through the mass media and government run forecasting services. Should our enemies hit us with an EMP all of this will come to a grinding halt.

Personal maybe even homemade barometers may make a comeback should this happen.

After all, we would still want to know when will storms be headed in our area so we can spend time cuddling with bae.

A barometer could possibly give some advanced notice of incoming foul weather.

However, all modern conveniences will be gone so will we actually have the time to cuddle with bae?

The weather might be the least of our worries as I’ve stated before and cuddling with bae might be highly frowned upon because cuddling sometimes leads to intercourse and intercourse ultimately means more hungry mouths to feed…