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Wednesday, December 27, 2017

Industrial Electronics- Building a Power Supply

Hey everyone! I am back from a bit of a hiatus due to my engineering classes at Florence Darlington Tech. I am working towards my degree in Electrical Engineering and due to the curiosity from friends on facebook I have decided to share a project I worked on this past semester.

I had to build a power supply and write up a report. Here goes:





To build a power supply, three circuit sections will be needed. Knowledge of transformers, how to build a filtered bridge rectifier, and how to build a voltage regulator is also necessary for this project. A transformer, four 1N4001 zener diodes, a 741 Op Amp, a 2N2222 Transistor, four resistors, a zener diode, and a capacitor will all be needed for this project.

To begin, we started with a step down transformer which was built with a 10:1 or rather a 0.1 turns ratio. This lowers the incoming 120Vac coming from the wall outlet. This particular transformer was center tapped so we could pick either 13vrms or 26vrms. We chose to wire it for 13vrms. Using the formula Vsec=(Nturns)(Vpri) we would come closer to 12vrms however Vrms from the wall can fluctuate within a range so for this report I will stick with 13vrms as it was already established on the transformer. 
In order to know that our transformer was working correctly we need to calculate the peak voltage expected on the oscilloscope screen. Rms=.707(vp) gives us an 18.387Vpp. The oscilloscope verified this by displaying a 18vpp (approximate) sine wave. The sign wave is far from the flat positive voltage we need for DC. 
To start smoothing this sine wave out, we need to build a bridge rectifier. To build the bridge rectifier, we wired together four 1N4001 diodes in this pattern:


We were careful to keep the positives and negative ends of the diodes in the proper direction. At one point, failure to double check our work resulted in the melting and untimely death of a few diodes. The capacitor and the load resistor were chosen to keep the ripple factor low. With a 20KΩ load resistor and a 10uf capacitor our ripple factor turned out to be 4.2%. We could have modified this by switching out the capacitor and resistor and using these formulas until we created the desired ripple factor:

Vp(rect)=Vp(sec)-1.4
Vr(pp)= 1/(fR_LC) x Vp(rect)
VDC= (1- 1/(2fR_LC)) X Vp(rect)
% ripple factor =vr(pp)/ VDC


Connecting the bridge rectifier up to the oscilloscope produced a 18vpp approximate ripple wave to appear on the screen. This is possible due to the diode positioning. During the positive half of the AC sinewave cycle, one pair of diodes conducts the current while the other two are reversed biased. As the negative half of the AC sinewave cycle passes the reversed biased diodes become forward biased and conduct current while the first pair become reversed biased. The process repeats itself bringing all the negative voltage into the positive. Like this:

Adding the capacitor into this circuit creates the sawtooth like ripple. This is created by the capacitor charging during the positive cycles when the diodes are forward biased and discharging as the cycle begins to drop (when the diodes are reversed biased). This created a signal on the oscilloscope like this (exaggerated):


This still isn’t flat DC though. We need to build a voltage regulator to smooth this out. For this we will need a 741 Op Amp, a 2N2222 transistor, three resistors, and a zener diode wired in this configuration:

A zener was chosen to set a voltage of 6.2 volts and R1 was chosen to be 1k to limit the current to the zener and help it maintain a nearly constant 6.2 volts no matter how high or low the incoming voltage goes as long as the current does not exceed the zener limits. In order to create a flat DC voltage this voltage level held by the zener holds the positive input of the op amp at 6.2v creating a reference voltage. Any time Vin decreases or the IL (the load current) increases (due to a decrease in the load resistance), and vice versa, the voltage divider created by R2 and R3 insures that a proportional increase or decrease is applied across the negative input of the op amp.
The difference between the two op amp inputs is amplified by the gain and sent to the base of the transistor. This change in voltage applied to the transistor causes the emitter at Vout to increase until the voltage to the negative op amp input matches the zener input at the positive terminal. This creates a flat DC voltage who’s voltage we can predict by plugging the zener reference value and the chosen R2 and R3 values into the gain formula:

Vout= (1+ R2/R3)Vref    ->      (1+(10k/10k)) x 6.2= 12.4V expected output.
The power supply was completed by connecting the two circuits together by a wire connected in parallel with the capacitor and resistor from the bridge rectifier circuit over to Vin of the voltage regulator:

Connecting the oscilloscope across vout and ground showed that the signal that was once sawtooth in shape was now a flat and solid 12V (approx) DC readout.

To test whether our power supply could handle a variable load we connected an 80k potentiometer at Vout in parallel with R2 and R3. Keeping an eye on the oscilloscope we were able to turn up the resistance to find where the transistor could no longer keep up with the current load (and could no longer keep the voltage at a stable 12volts). As the transistor failed this caused the signal on the oscilloscope to become distorted once again. We unplugged the potentiometer and tested the resistance with a meter to find that the transistor was able to handle the current and keep a steady 12v signal going to the output as long as the resistance of the load stayed under 6K.

Using what was learned in this project it would be possible to replace pieces of the circuit to create a power supply that could operate at higher voltages or tolerate wider load resistance variances. It was very interesting to see firsthand how each part of the circuit worked individually and then how they changed the Ac to Dc once they were connected together. The greatest challenge for me during this project was making sure the diodes in the rectifier were all going in the proper directions and figuring out where everything was in relation to the diagram once we started adding the circuits together. 



  If you have come this far (Holy smokes CONGRATULATIONS!) and have questions (I'm sure you do!)... feel free to leave them in the comments or reach out to me on facebook/twitter ;)

Also, hit the subscribe button because I will be going back to writing sci-fi short stories on my blog as well as entering in updates on my current work in progress which should be out of edition hopefully before May 2018... Just in time for ConCarolinas- I hope.

Meanwhile... run on over to Amazon to get the updated edition of The Alien Mind on kindle for just $0.99 till Jan 1st (afterwhich it returns to $2.99)!

Till next time-> Never stop reaching for the stars and exploring your potential!



Friday, October 27, 2017

E-books or Physical Copies for Teens?

So, I heard something today, will not name names or point fingers but it made me sad. The comment was that certain schools are being encouraged to shy away from physical books in their libraries in favor of e-books. While I do enjoy e-books, I don't think they are always a good fit for children.

The reasons for a school district to advocate for e-books are admirable:

Less paper
Less fire hazard
Takes up less space
E-books can be checked out and re-checked out where physical copies eventually come into too much wear and tear.

However, remember dear readers where you first learned to love reading. It wasn't sitting in front of your computer. It was in a library! Staring down all the rows of pretty book covers and waiting for a cover to jump out and grab your attention! This is how you found new books too! You picked up a copy of a new book that was unfamiliar to you and you read the back description. Maybe you decided to try out the first few or last few pages.

The feel of the cover. The feel of the pages between your hands. The atmosphere developed by the way the text and/or illustrations were presented in the book. All of these things helped stimulate your decision to take the book home for the week or not!

E-books are great too, don't get me wrong. Amazon's kindle program even has a way to allow authors and publishers to add extra details like character and location descriptions, or even definitions with their kindle x-ray feature. (look for the "x-ray enabled" notation on the amazon book page) This makes a book more three dimensional and can even further the reader's learning if they come across a link that teaches them something they never knew! If the e-book reader comes with a 'read aloud' feature, that could certainly help those who struggle to read as well.

Do I think schools could successfully transition to e-book only? Sure. The problem is enabling the "find a new book" phenomenon that comes so easy with physical books. Perhaps large screens could take the place of shelves and display rows of book covers with the book description... this would take a lot of money that most schools just don't have. Plus, can you guarantee that each child in your district has an e-reader (or is capable of being responsible for one?).

Where I stand right now... I believe with my entire being that children of all ages need to have access to a diverse physical library within their schools. Not every student can get their parents to take them to the public library. I believe that without a drastic change in how we store and display e-books, that ebooks could have the effect of turning children AWAY from reading. With less physical books trying to grab their attention replaced by nothing but hyperlinks on a webpage... I feel that less children and teens will even bother to read.

Keep the e-books for the busy adults who don't have space in their already full briefcases for a physical book.

Long live the physical libraries stocked full of paperbacks and hardbacks beckoning every young adventurer to come and sit a while!



Library photo credit: Enokson Book Talker Hangers via photopin (license)


Meanwhile...


If you would like a Signed Copy of The Alien Mind I would be more than happy to send you one!

You can email me at jennings (dot) vlj (at) hotmail.com or send me a private message on facebook (@vljennings)- which is often faster.

Paperback copies of the new edition are 14$ and Hard Covers are 24$. Both prices include shipping!

I also provide free digital copies to reviewers.

Monday, September 11, 2017

What Is The Shadowzone?


My guest today is Calgary author Simon Rose, who has published fourteen novels for children and young adults, seven guides for writers, almost 100 nonfiction books, and many articles on a wide variety of topics. Earlier this year he released Twisted Fate, the second installment of the paranormal Flashback series. Today, we’re looking at his latest release, the Shadowzone series.


So what’s the Shadowzone series all about?

The series involves the discovery of a grim dystopian version of Earth that’s ruled by a totalitarian dictatorship, the threat of a deadly virus, and a race against time to save the lives of millions. Without giving too much away, here’s a synopsis for each of the novels.


While watching intense flashes of lightning during a violent storm, Ben experiences mysterious and disturbing visions of another world, one very different from his own. In the chain of events that follow, Ben encounters Charlie, a girl from a dark version of Earth, a planet doomed by the effects of environmental catastrophe, where the leaders will stop at nothing to complete their deadly mission. 




Into the Web


On a doomed version of Earth, the sinister schemes of the Ministry are moving ever closer to completion, with dire consequences for the inhabitants of two worlds. For Ben and Charlie, an unlikely alliance, unexpected reunions, and the mysterious prophecy of the Chosen One offer a glimmer of hope, with the ever-present prospect of betrayal, as they embark on an unpredictable journey into the unknown. 


In a dark parallel world, following attacks by its most determined opponents, the Ministry has been forced to change its plans. Yet the ruthless Director-General is prepared to sacrifice anyone to achieve an entirely new beginning, no matter what the cost. In a deadly race against time, as events spiral out of control, Ben and Charlie must risk their lives in a desperate attempt to save two worlds from destruction. 




What inspired you to write these three books? What’s the story behind the story?

The original idea was about someone capturing mysterious images on a video camera of a person that no one else could see. It was around the time that a local hospital was about to be demolished. I imagined that my character was filming the event and captured the image of the person stepping seemingly unharmed from the rubble as the building came down. The idea of capturing unexplained images on film was something that I’ve continued working on and it also inspired me to write The Time Camera, which was published in 2011.

For a while, that’s all I had and it was one of those ideas that I was never sure would come to anything. It was early in my writing career and I put it aside and worked on other stories, but I’d periodically add another element to the story about the camera and the mysterious individual. At one point, I decided that the person that the boy caught on film wasn’t a ghost but from another dimension or perhaps a parallel universe and they were attempting to contact him for some reason. I then began to add details of this other Earth and the reasons for the connection to our world, and it went from there. An initial concept involving kidnappings from hospitals didn’t quite work, so instead I developed the idea of a deadly virus, which was a good fit with the type of government running the other Earth. Once that was all in place, I was able to get to work.


Was it always going to be a series?

Shadowzone was originally only one novel, but once I’d finished it I immediately realized that the story wasn’t over and that I need to write more. The final installment was written very quickly and in the process I knew that I needed to expand the earlier sections too, so in the end I had a trilogy.


 So of course, people need to read all three :)

You could certainly just read Shadowzone, but there’s a cliffhanger ending and hopefully most people will feel utterly compelled to be read on and learn what happens next. Into The Web and Black Dawn also don’t make sense if you haven’t read the first book in the series. Taken together, it’s an exciting, fast paced adventure that I hope everyone will really enjoy.


So it’s a good idea for authors to write a series of books?

It can be, but only if you have enough material for multiple books. If readers are sufficiently interested in the story and the characters after completing the first installment, they’d usually like to read more. However, the story or theme has to be strong enough to warrant more adventures. It’s important to remember that the reader won’t appreciate any novel that’s overloaded with filler, just for the sake of creating a series, and might easily avoid any books by the same author in the future.


So where can people buy all three books in the Shadowzone series?

The books can be purchased at most of the usual places, as follows:

Shadowzone
Paperback: AmazonCreatespace

Into The Web
Paperback:

Black Dawn
Ebook: Amazon CanadaAmazon USAKoboiBooks, and Smashwords
Paperback: 
AmazonCreatespace


You published these yourself, whereas most of your earlier work was traditionally published, correct?

The first eight novels were published by Tradewind Books, while Flashback, Future Imperfect, and Twisted Fate were published by Tyche Books, but my seven books featuring tips and advice for writers were self-published as paperbacks and as ebooks.  I hadn’t self-published fiction before and thought it was time that I did. The Shadowzone books were finished and I believed that they were as good, if not better, than my other work. I also asked some people read them to confirm this and then decided to go ahead with publication. A lot of traditionally published authors also self publish as well now, so it’s quite common practice these days. 


Will you self publish again in the future?

Yes, I think so. The third part of the Flashback series will be published by Tyche Books next spring, but I do have several other projects that I’ll most likely publish myself as well soon. 


What are you currently working on?

I always have a current project or two and right now I’m working on a historical fiction novel for young adults set in the turbulent era of the English Civil War in the 1640s. The novel’s about half finished, but I still have a lot of work to do. I’m also working on sequels to Future Imperfect and The Sphere of Septimus.


Are your other books in this similar dystopian genre?

No, although my novels are all in the science fiction and fantasy genre. The Sorcerer’s Letterbox and The Heretic’s Tomb are historical fiction adventures set in medieval England, The Alchemist’s Portrait is a time travel story, The Emerald Curse is all about superheroes and comic books, The Doomsday Mask is all about the legend of Atlantis, and The Sphere of Septimus involves the characters traveling into another world and is in the same vein as the Harry Potter series, The Chronicles of Narnia, or Lord of the Rings. Future Imperfect is a technology-driven story featuring mysterious messages from the future, and Flashback and Twisted Fate are in the paranormal genre. I’ve also written nonfiction guides for writers, including The Children’s Writer's Guide and The Time Traveler’s Guide.


You also work with other authors, don’t you?

Yes, I do quite a lot of that these days. I’ve edited books in all kinds of genres for a wide range of writers in the last few years, offering both substantive and copy editing. I also work as a writing coach and consultant for people with works in progress or those that are struggling with writer’s block. You can learn more about some of the projects I’ve worked on that have subsequently been published are here on my website. I also offer online courses for adults and workshops on a variety of themes for aspiring young writers.

Thanks Simon, for being my guest here today and the very best of luck with the Shadowzone series. I hope the books sell thousands of copies in the coming weeks and months.

You can learn more about Simon and his work on his website at www.simon-rose.com or online at the following social media sites:

·         Facebook
·         Twitter
·         LinkedIn
·         YouTube
·         Google +
·         Pinterest

Thursday, September 7, 2017

Excerpt From- Dating The It Guy

Krysten Hager is the first YA author I've had the privilege of having on my blog in a long time and I am really excited about her book "Dating The It Guy". I hope the excerpt she's shared with us intrigues you as much as it did me! Help support the author by running out and buying a copy! 😊

Dating the It Guy by Krysten Lindsay Hager- YA contemporary romance

Dating the it guy by Krysten Hager
About the book:
Emme is a sophomore in high school who starts dating, Brendon Agretti, the popular senior who happens to be a senator's son and well-known for his good looks. Emme feels out of her comfort zone in Brendon's world and it doesn't help that his picture perfect ex, Lauren seems determined to get back into his life along with every other girl who wants to be the future Mrs. Agretti. Emme is already conflicted due to the fact her last boyfriend cheated on her and her whole world is off kilter with her family issues. Life suddenly seems easier keeping Brendon away and relying on her crystals and horoscopes to guide her. Emme soon starts to realize she needs to focus less on the stars and more on her senses. Can Emme get over her insecurities and make her relationship work? Life sure is complicated when you're dating the it guy.

 Excerpt:

“By the way, did you hear Lauren got into Senator Agretti’s old school?”

“Seriously? I wonder if she applied there because Brendon did,” I said.

Margaux snorted. “Duh, of course. Seriously, she might as well just pee on him to mark her territory.”

“Margaux, shut up,” Kylie said.

“Whatever. Anyway, the important thing is if Brendon knew she was applying there,” Margaux said.

 “Em, do you think he knew?”

I hoped Lauren was just trying to follow Brendon, but what if they had planned this whole thing while they were dating? What if he convinced her to apply there so they could go to college together, wear matching American flag sweaters with big scarves while drinking hot chocolate, and jump into leaf piles just like a preppy clothing catalog. At least now I didn’t have to worry about them reciting poetry to one another in South Bend, but still, what if they had made plans to go to school together?

“Don’t worry about it,” Kylie said. “She was probably trying to follow him—like she always does. She’s so pathetic.”

Kylie was trying to make me feel better, but Lauren was far from pathetic. After all, she was pretty much the “Most Likely to Succeed” poster girl. While she was out overachieving and saving the world without messing up her perfect, bouncy hair, I was trying to get through each day. I tried to push away the image of Lauren and Brendon holding hands and drinking hot chocolate under a stadium blanket.

Purchase:

Praise for Dating the It Guy:

*“Dating the It Guy is an entertaining story that is as absorbing as it is hilarious.” Reviewed by Arya Fomonyuy for Readers' Favorite

*A satisfying YA romance that is really about growing up and learning how to deal with life.” Writing Pearls book review blog

*“There is so much to love about this book. Krysten Lindsay Hager knows how teens think and speak, and she understands why Emme would feel overwhelmed by everything about Brendon - his looks, his popularity, his feelings for her, his exes, his family.” Vox libris: the voice of books book review blog


 *“A sweet, endearing story—you’ll fall in love with Emme just like I did!” --Kimber Leigh Wheaton, YA/NA author

About Krysten Hager:


YA Author Krysten Hager
Besides mining her teen years and humiliating moments for her novels, Krysten is also a book addict who has never met a bookstore she didn’t like. Krysten writes about friendship, self-esteem, fitting in, frenemies, crushes, fame, first loves, and values. She is the author of True Colors, Best Friends...Forever?, Next Door to a Star,  Landry in Like, and Competing with the Star (The Star Series: Book 2). Her debut novel, True Colors, won the Readers Favorite award for best preteen book and the Dayton Book Expo Best Sellers award. Krysten's work has been featured in USA Today, The Flint Journal, the Grand Haven Tribune, the Beavercreek Current, the Grand Blanc View, the Bellbrook Times and on Living Dayton.

Follow Krysten:


Tuesday, August 22, 2017

Solar Eclipse 2017 Pictures From Totality in Columbia SC

Warning... Photo heavy post. Pictures from totality tailgating at the South Carolina State Fairgrounds in Columbia where we witnessed 2.5 minutes of awesome jaw dropping totality!

The clouds tried to have their way-(which made for some interesting views and images) but by the grace of God we were able to have some large chunks of time where the sun was completely clear of the clouds. Totality was completely unmarred by the clouds.

I was able to take pictures of the sun leading up to totality (partial eclipse) both through my telescope and through my phone. I used a pair of solar lense glasses over my phone. For my telescope pictures, my telescope had a solar filter at the top, so I could lay my phone on the eyepiece to photograph what I could see in the telescope. I was impressed at how well the images came out actually (for a phone camera that WASN'T actually mounted to the telescope- I didnt think it would work as well as it did.)

I was able to show my children (ages 6, 13, and 16) sun spots during this time (some of which show up in the pictures. As well as what the solar eclipse looks like through the telescope. We all had glasses so we could view it with our eyes too.

The spectacle of seeing the sky go dark during the day, the stars come out, and the sun disappear except for a thin shiny silver ring was as awesome as one would expect. The air cooled (THANKFULLY) and the atmosphere took on an eerie feeling. Everyone cheered as the last bit of sun hid itself behind the moon.

NOTHING, however, can compare to the shock and awe I felt when I spared a moment to look down into my telescope during totality (AFTER I remembered I needed to take the solar filter off if I expected to see anything during that time lol). The effect through my telescope was so shocking that I exclaimed out loud "Oh my gosh!". I've never been so completely shocked at what I've seen through my telescope until that moment. I've been intrigued in the past, as I've found saturn, or jupiter. But this was a feeling of 100% total amazement. A once in a lifetime sight!

Then I took a moment to tighten my telescope down and begged everyone else to come take a peek. I loved watching everyone else experience that too! My middle son exclaimed "I want to be a scientist now!" We saw at least two 'stars' during this darkened moment, one of which was rumored to be a planet- but I did not have time to confirm that with my telescope or charts.

I went back to take pictures through my telescope by setting my phone on top of the eyepiece right before totality ended. Then... far too soon (wish we had longer) some blessed stranger was broadcasting a radio program that called out a countdown for "glasses on"- which meant I needed to get my face away from my telescope and put that solar filter BACK ON the darn thing before I fried my retinas. Thank you dear stranger!

The ring started to grow larger and our focus was drawn to the shadows returning slowly on the ground as the sun started to come back out once again! Totality cleared and the moon started its recession. We had to fight traffic back out of columbia so we didn't stay for the whole recession but every moment was completely worth the hours of traffic jams afterward!

Oh and one other thank you to the couple that we shared our tent with ;) Our tent was a bit big for the space, so thank you for letting us share it with you! It was awesome getting to hang out with you guys!



More Pictures!

I apologize that these are not in order, I will go back later and put them into order and add more captions.

Dusk Before Totality





Clouds fogging up the shot



some of the red tint is from my phone case reflecting off the solar glasses





Another image through my phone

Pictures through my telescope with solar lens cap




Another through my phone



Through my phone right before totality