Category Archives: Commentary

Opinions

Ego 7.5AH Battery capacity over time (Battery Degradation over time) – 4 year update

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I own three 7.5AH Ego batteries. My earliest had a manufacture date of 2014 (although I purchased it in 2017 with a mower manufactured in 2016). I now have four years of operation on this battery.

As shown in the graph, the capacity dropped off over time (down to a low of 260 watt hours in year 3, which is 63% of the original 410 watt hour capacity), but in year 4 it has actually increased a bit to 290 watt hours (70% of the original capacity).

My 2nd 7.5AH battery was purchased in July of 2018 (manufactured in May of 2018).

As you can see, its graph has gone down, and so far hasn’t popped back up.   At the three year mark it is also down to a 260 watt hour capacity (63% of it’s new capacity).

My third 7.5AH battery has a 2019 manufacture date, but it’s still in its first year of “use”, so I don’t have a fancy graph for it yet, although I have started to include it in the comparison bar graph below:

So far, all three of my 7.5 AH batteries have followed a very similar capacity vs time curve, and you can expect one of these batteries to retain an average of 90% capacity in year 1, 72-75% capacity in year 2, and 63% capacity in year 3.

[Plus, they MAY bounce back up to 70% capacity in year 4, if the other two follow the path taken by my first battery.]

Capacitive Touch Button Failure on Looking Glass Portrait can be solved with a better USB-C PD power supply

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I’ve had re-occuring issues with Looking Glass Portrait displays where the touch sensitive capacitive buttons (Forward, Back and Play/Pause) would not work. (Either straight out of the box, or intermittently.)

After a lot of back and forth with Looking Glass (and them shipping me 4! replacement units) I was finally able to determine that the issue is the provided CHOETECH USB-C 20W PD power supplies. (Which apparently don’t work well on the 110-113 volts AC at my house, even though they are rated at 100-240 volts AC….)

I’m not sure if it is a power issue, or some type of noise/frequency that the power supply generates when running on voltages close to the bottom end of its range, but I can reliably fix the issue by changing over to using my Google Pixel 4A USB-C PD power adapter to power the Looking Glass Portrait.

 

 

It’s August 1st, 2021, how is Orange County doing with COVID-19?

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For the week ending July 29th 2021, Orange County Florida had an average of 1,130 new cases per day. The test positivity rate over the last week was 18.2%.
This is worse than the highest previous peak in January.   The exponential growth can be blamed on the Delta Variant and the relaxing of masking and social distancing.

Historically, Orange County has had a case fatality rate of near 1%, so that would indicate we are due to see about 11 deaths per day in the near future, but as death numbers are no longer part of the FDOH weekly reports for counties I have no way of knowing if the case fatality rate has started to drop due to vaccinations of high-risk groups or has increased due to the Delta variant.

We have vaccinated (at least a first dose) 780,452 people (out of a population of 1,457,445, or 54% of the total. If you discount children 12 and under who are not yet eligible for vaccination, Orange County has vaccinated 63% of the eligible population.   We vaccinated 62,349 people in July (Compared to 65,206 in June, 88,482 in May and 151,176 in April.)

Hospitalizations

Although the FDOH is not reporting county level hospitalization numbers, we can assume that the admissions curves for Orange County are similar to the entire state of Florida.

AdventHealth has entered ‘black’ status and postponed all non-emergency surgeries confirming that they have more hospitalizations than in January, which matches the state level graph.

Nursing Homes

We are seeing a small uptick in covid-19 cases in nursing homes. According to the AARP, in Florida’s nursing homes “Roughly 3 in 10 nursing home residents and 3 in 5 health care staffers are not fully vaccinated. The state’s nursing home vaccination rates are well below national averages”.

End in sight?

In the United Kingdom, which was hit by the Delta variant earlier than the US, daily case numbers are starting to drop.   It may be possible that through vaccinations and “naturally obtained immunity” that the UK is reaching the herd immunity threshold. As the delta variant tears through the remaining unvaccinated population in the US we may see a corresponding drop in infections next month.

The Delta Variant, and why case numbers in Florida will continue to go up in July

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The Delta variant of the SARS-COV-2 virus is a version/mutation of the virus that causes COVID-19 in humans that happens to be significantly more transmissible than previous variants. This means that when the delta variant is introduced to a region, it will “take over” and become the predominant variety of SARS-COV-2 that is circulating. Because it is easier to transmit/catch, the number of cases also tends to go up in that region.

All of the following graphs are from the great covariants.org website. I encourage you to check it out and look at all of the country and state graphs.

For example, in the country of India, Delta (dark green in the graphs) was at 7% of all sequences in the March 8-22nd timeframe, and grew to 91% in the May 3-17th timeframe.

This pattern of Delta out-performing all other variants repeats in other countries and US states where it is introduced.
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Failed Kickstarter projects

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Over the years I’ve backed sixty seven kickstarter projects. Seventeen were comics, graphic novels, audio books or magazines. Thirty-nine were hardware/physical product based projects. Five were software development efforts (open source libraries or software products, games….). And there were a few miscellaneous “support this group to do this thing” type of projects, or things where I only pledged $1 or $10 just to lend moral support.

My first failed KickStarter  (after 12 successful ones) was CST-01: The World’s Thinnest Watch
thin band e-ink wristwatch

The founders were very ambitions, and made great progress, but just didn’t have enough funding for this particular hardware project. I really wish that some company would pick up and run with this idea, because I still want one.
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It’s July 2nd 2021, how is Orange County Florida doing with Covid-19?

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Well, it’s hard to tell for sure, as the Florida Department of health has stopped issuing daily reports, and has switched to weekly reports. They have also stopped releasing per-county death numbers, among other omissions and simplifications.   You may notice that the graph I have to display is simplified this month.


What we do know is that the number of cases per week had been decreasing since mid-April, but in the last two weeks the number of cases per week has started to increase again. On June 1st the 7-day average was 145 cases per day, while as of July 2nd it is 171 cases per day, and the case positivity rate has raised to 5.3%.

Historically, Orange County had a case fatality rate of near 1%, so that would indicate about 1.7 deaths per day, but those numbers are no longer part of the FDOH weekly reports so I have no way of knowing if the case fatality rate has started to drop due to vaccinations of high-risk groups or has increased due to the Delta variant.

We have vaccinated (at least a first dose) 718,103 people (out of a population of 1,457,445, or 49% of the total). If you discount children 12 and under who are not yet eligible for vaccination, Orange County has vaccinated 58% of the eligible population.   We vaccinated   65,206 people in the month of June. (Compared to 88,482 in May and   154,176 in April.)

The rate of vaccination has slowed and I expect it to continue to slow, while the total number climbs upward slowly. I expect that fewer than 60 thousand people will be vaccinated in July.

I believe the uptick in case numbers is primarily among the un-vaccinated 51% of the population, due to a combination of the more infectious Delta variant and relaxation of mask usage and social distancing.

[Charts/Numbers used can be found in this open document spreadsheet: orange_county_florida.ods ]

Ring app on Android (3.40.0) suddenly became a background data hog

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In the month of May, the ring app cost me $40 (I pay $10 a GB for cellular data).

Having the ability to see what is going on around the house when I am away is worth spending some mobile data on…in March it cost me 54MB, and in April it cost me 318 MB (54 cents and $3.18 cents respectively). However, that is FOREGROUND data, that is actively used when I am streaming data in the app. Sometime after May 5th, the ring app started to download a LOT of background data. In fact, for the May5-June 4th month, I used 91 MB of foreground data, and the ring app used 3.95 GB of background data (that’s $39.50 it cost me).

[Soon after taking these screenshots, I disabled “Background data” for the ring app, which prevented it from using more excessive amounts of (cellular) data and costing me money.
Ring app using 4 GB of background data in a month

My current version of the ring app is 3.40.0, running on Android 11 on a Pixel 4A phone.
After I got the $40 larger than I was expecting bill in June, I quickly checked to see what was using all of that data, and found that the Ring app had used 1.27 GB of data in only a few days. To put that in perspective, it was using more data than Pokemon GO, which is usually my highest data using application.

 

The problem is not limited to cellular data, the ring app has become a massive data hog when on wifi as well (but at least since my wifi connection is not metered, it doesn’t cost me anything). Every so often when I am at home I will use the ring app to watch the video feed from a camera if I get a motion alert and don’t want to get up to look out the window. In March and April this usage amounted to around 1 GB and 1.7 GB of wifi data respectively.     But, in May, the ring app used 61 GB of wifi data!
I did not stream more video in May than in previous months, so this is primarily background data usage by the app.
Ring using 61 GB of wifi data

If I had to guess, I suspect that the ring app on android has started automatically downloading videos of motion that occur, EVEN IF THE USER DOES NOT WATCH IT! Perhaps this a feature designed to make the app more responsive if the user selects the notification to view the video stream, but when I talked with technical support, they could not offer any explanation for why this was happening or how to disable the high data usage.

Update – Ring app 3.41.0 appears to have fixed the issue

After the Ring app upgraded to version 3.41.0 on Android, I re-enabled background data and kept a close eye on it for a few days. Including a few times I was away from wifi on cellular data, the data usage was much more reasonable, so it appears that the ring developers have fixed whatever the issue was.

2.47 mb of data used over a few days

 

Making bc use scale=8 (or any other configuration) every time you start it.

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If you use bc (a command line calculator) frequently, you probably want floating point division by default. You can type “scale=8” every time you open it, or you can set up some environment arguments to have that be your default every time you open it.

Create a .bc file in your home directory that includes:

scale=8

Edit a file that is executed every time you log in (such as .bashrc) to include the line:

export BC_ENV_ARGS=~/.bc