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Quorten Blog 1

First blog for all Quorten's blog-like writings

Stocks and Coronavirus part II: Working out specific number of shares to invest

quorten

2020-03-02

Categories: personal-finance   covid19  
Tags: personal-finance   covid19  

In my previous article about the effect of the Coronavirus outbreak on the stock market, I’ve outlined some general guidance on how to pick stocks to invest and in what quantities. For me, the baseline investment around $1000 turned out to work out quite well on its own. Let’s convert that into the number of shares using only a single point-in-time snapshot today, 2020-03-02.

$200 for 1/1x investment

AAL:   American Airlines, 1/1x       = $200.000
DAL:   Delta Air Lines, 1/1x         = $200.000
LUV:   Southwest Airlines, 1/1.3x    = $153.846
UAL:   United Airlines, 1/1.3x       = $153.846
ACDVF: Air Canada, 1/4x              =  $50.000 (OTC market)
ALK:   Alaska Air Group, 1/4x        =  $50.000
JBLU:  JetBlue Airways, 1/4x         =  $50.000
SAVE:  Spirit Airlines, 1/6x         =  $33.333
ALGT:  Allegiant Travel Co., 1/12x   =  $16.667
HA:    Hawaiian Holdings Inc., 1/20x =  $10.000

Total $917.692

Now, dollars to shares:

Read on →

Program an Arduino using SPI on Raspberry Pi, and configuring the stock ATmega 328 chip to run at 3.3 V

quorten

2020-03-01

Categories: raspberry-pi  
Tags: raspberry-pi  

Want to get started with Arduino by buying just the plain ATmega 328 chip rather than a full development board? The first question to answer is how to get the initial programming performed to setup the bootloader. For that, the ATmega’s common programming mode is In-System-Programming (ISP), which is basically an interface over SPI with a little other pin wiring magic. It’s really simple to build the circuit to interface with Raspberry Pi, then you can just use avrdude on the Raspberry Pi to complete the programming.

20200301/https://en.wikipedia.org/wiki/AVR_microcontrollers#Programming_interfaces
20200301/DuckDuckGo raspberry pi spi isp program atmega
20200301/https://www.instructables.com/id/AVRArduino-Flashing-With-Raspberry-Pi/

Also related, can an ATmega 328 operate at 3.3 V? Yes it can, the main point to be aware of is that you can only run at half the clock frequency of 5 V operation. Also, you must reprogram the ATmega 328 to use the proper “fuse settings” that allow it to run at 3.3 V logic. This programming can be done over SPI. In particular, due to the clock frequency switchover, you want to configure it so that it uses its internal clock rather than external crystal.

20200303/DuckDuckGo atmega 328 run at 3.3 v
20200303/https://forum.arduino.cc/index.php?topic=122783.0

More info on selecting decoupling capacitors

quorten

2020-03-01

Categories: raspberry-pi  
Tags: raspberry-pi  

The Wikipedia article on decoupling capacitors specifies a 100 nF ceramic capacitor per every logic chip, with more for complex logic chips. But can you get away with less if you are using simple logic and low frequencies? Yes. 10 nF ceramic capacitors per every cluster of quad NAND integrated circuits appears to work well. You could also use 22 nF. 100 nF per chip is primarily needed for faster circuits.

But one important key, when you pick a decoupling capacitor value, try to stick with the same capacitor values consistently throughout the circuit. Otherwise, you can get other problems.

And, remember, the power supply source typically has a decoupling capacitor of a few hundred uF.

20200301/https://en.wikipedia.org/wiki/Decoupling_capacitor
20200301/DuckDuckGo decoupling capacitor quad nand ic
20200301/https://www.cypress.com/file/135716/download
20200301/https://www.reddit.com/r/electronics/comments/870wj0/8bit_alu_made_using_only_quadnand_ics/

How to unset "manually installed" on an apt package

quorten

2020-02-29

Categories: unix  
Tags: unix  

So you’ve done an apt-get install on a package that was already automatically installed. What if you don’t want to uninstall it, but simply remove the “manually installed” mark? The solution is simple:

apt-mark auto zlib1g-dev

20200229/DuckDuckGo dpkg unset manually installed
20200229/https://serverfault.com/questions/87933/how-to-remove-the-installed-manually-flag-and-revert-to-automatically-install

The effect of the Coronavirus outbreak on the stock market

quorten

2020-02-29

Categories: personal-finance   covid19  
Tags: personal-finance   covid19  

Over the past few weeks, stock prices have dropped 12% across the board. Yes, pretty much all stocks are down 12%, and this is reflected in index funds like Vanguard Total Stock Market Index Fund (VTI). What’s happening? As news has it, it’s the Coronavirus scare that’s at fault.

Okay, so there’s a lot of overly sensationalized news out there about how people’s behaviors are changing in light of the Coronavirus outbreak, but are some of the claims legitimate? Sure, some are, but most are not, as we will see from our deeper analysis.

Better yet, the question to ask with the stock market is this: Which stocks have a great opportunity opened up for buying? With everyone loosing confidence in the stock market, stock prices are going down and the “clearance isle” effect is providing an excellent opportunity to buy valuable stocks at a low price. Chances are that the Coronavirus outbreak will be limited in time, so when the stock market resumes back to normal, low-valued stocks today will grow to a competitively higher value in the future.

First of all, let’s start with the essentials of the Coronavirus outbreak. The Coronavirus originated in China, and our main fear of its spreading is through international transportation, in particular human international travel because (1) it typically uses the fastest means of travel such as air travel and (2) humans are living creatures that function as a better host for the Coronavirus than, say, the surfaces of raw materials and manufactured goods.

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Warren Buffett's advice for a stock market crash

quorten

2020-02-28

Categories: personal-finance  
Tags: personal-finance  

This is a really good article on Warren Buffett’s advice for a stock market crash, lots of good points stated. Keep a level head, remember that when you invest in stocks, you are a business owner and these are businesses, not just ticker symbols. If they have good business behind them, things will work out well in the long run even if they are not doing well in the short run.

20200227/https://www.fool.com/slideshow/warren-buffetts-advice-stock-market-crash/

Solar powered barges scooping up plastic from rivers

quorten

2020-02-27

Categories: random  
Tags: random  

Interesting, a solar powered barge that scoops up plastic from rivers to prevent it from accumulating in the ocean. 1% of rivers are responsible for 99% of ocean plastic pollution, so why not stop the pollution at its source?

20200227/https://returntonow.net/tag/solar-powered-barge/

Vertical video criticism, and its later embrace

quorten

2020-02-27

Categories: media-prog  
Tags: media-prog  

Vertical Video Syndrome (VVS)? Wow, now here is quite a criticism recording videos vertically on smartphones.

20200227/https://www.youtube.com/watch?v=f2picMQC-9E

But, what does Wikipedia have to say? According to Wikipedia, although vertical video was initially shunned by video professionals, it later came to be embraced once it was discovered that the majority of video watching happens on smartphones, and vertical video viewing is the overwhelming preference on smartphones.

20200227/https://en.wikipedia.org/wiki/Vertical_video

Here is more great information on the rise of vertical video.

20200227/DuckDuckGo vertical video
20200227/https://www.forbes.com/sites/forbescommunicationscouncil/2018/02/02/the-rise-of-vertical-video-how-top-brands-are-adopting-a-new-content-format/
20200227/https://www.wyzowl.com/vertical-video/

GitHub pages Markdown syntax highlighting

quorten

2020-02-27

Categories: blogging  
Tags: blogging  

Many times I’ve tripped over this, you’ve got to be careful when using triple backticks, Kramdown Markdown will try to auto-detect the programming language for syntax highlighting, but if it fails, your GitHub pages will fail to build. Sidestep the problem entirely by specifying the programming language explicitly at the beginning of the three backticks. See a list of supported syntax highlighters here.

20200227/https://stackoverflow.com/questions/11568093/syntax-highlighting-on-githubs-wiki-specifying-the-programming-language
20200227/https://pygments.org/docs/lexers/

All my Golang Meetup notes not written

quorten

2020-02-27

Categories: golang  
Tags: golang  

I’ve went to a number of Golang Meetups, but I haven’t had a clear and formal way to keep track of my notes as well as I should have. Well, now I do, I’ll keep up with putting things in blog articles.

First of all, using kernel level system calls and routines from Go to build your own containers implementation from scratch, like a simpler Docker.

20200226/https://www.meetup.com/Minneapolis-Golang/events/259934939/
20200226/https://github.com/jackspirou/toycontainer
20200226/DuckDuckGo liz rice containers from scratch
20200226/https://github.com/lizrice/containers-from-scratch/blob/master/main.go

Next, flowgraph, a flow-based programming system that works well with concurrency in Go.

20200226/https://www.meetup.com/Minneapolis-Golang/events/259276080/
20200226/https://github.com/vectaport/flowgraph

A presentation on how package management and Go modules work.

20200226/https://www.meetup.com/Minneapolis-Golang/events/261677345/
20200226/https://github.com/jesselang/presentations
20200226/https://github.com/jesselang/go-module-example

Play around with TinyGo: microcontrollers, web assembly, yes, new targets for TinyGo.

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