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The Proof: Poor USB cables slow phone charging by 77%

Inexpensive cellphone charging cables, commonly sold online, at drug stores, and at discount stores can exhibit poor phone charging speed. Some times the charging performance is so poor that people think their phone has gone bad. Here, I'll show how cheap cable construction can compromise charging performance. Verifying Cable Quality The following experiment is designed to show how bad cables ruin charging speeds. I will be measuring various USB extension cables to experimentally show how poor cable construction can have a significant negative impact on smart phone charging rates. In order to standardize the experiment and eliminate variables, I will be using a genuine Apple "1 Amp" USB charger along with a genuine Apple USB lightning cable. These components were delivered new by Apple with my iPhone 11, so I know they are "legitimate" (not clones or counterfeits). They are name brand components sold by a reliable retailer. But I'm not here to test these w

Broken Dishwasher 2: Fails to clean due the rack?

A friend of mine gave me a dishwasher he was throwing away.  It looked great and it was relatively new, but it wasn't cleaning well.  He decided to punt and buy a new one instead of fixing it. I figured I needed a dishwasher for an apartment I manage, so I took it.  Now it is installed, even before I attempted to fix it.  Despite its looks, I still know that it is still problematic.  Now I want to figure out what's wrong.  I guess it is easier for me to figure out its issues when it is hooked up. Step 1: In-situ inspection It looks very dirty.  It has been sitting around for about a year and is covered with construction debris and etc.  A little cleaning will hopefully make it look better.  Fortunately, there are no dents! There is one weird thing: the top dishwasher rack is somehow binding to the back of the dishwasher, where the water feed connects to the central arm. Step 2: Diagnosing the rack binding issue. I remove the upper rack, and then it is clear: one of the rear whe

Broken Dishwasher Makes Noise? Not so fast. It's my hot water pressure.

My dishwasher hasn't been cleaning dishes well.  It is about 12 years old... is time for a new one?  The short answer is no. A new dishwasher will not fix my problem.  It turns out that my kitchen's hot water flow is very low, and so my dishwasher is not filling up with enough water.  Buying a new dishwasher won't fix this, so therefore I won't be buying a new dishwasher. [ UPDATE!  After a 12+ months of suffering, I solved all my dishwasher problems by flushing my kitchen's hot water plumbing!  See this post for more information. ] How the Dishwasher Inlet Valve Works My dishwasher fills up using a timed water valve. Given reasonable water pressure, my dishwasher accurately accepts about 3 gallons of water per cycle in 95 seconds.  If the water flow is very low, then less water comes in over those 95 seconds.   If water pressure is decent, the dishwasher fills until a float switch is triggered.   If the dishwasher doesn't get enough water, the pump still runs

Loving the chemistry companies

I believe in soap.  I believe in glue.  And I believe in the chemists and chemical engineers that design them and make them. There are a lot of cleaning products on the market that purport to be "green" and "all natural", but all their claims mean nothing if they can't prove that they work and that they're actually better than the real deal. In short, I'm going to trust a "Tide" or "Cascade" long before I trust a "Ellen's Hypoallergenic Natural Suds".  Because Ellen is certainly trying to sell me a line, and Ellen's is sold by someone that knows nothing about what natural, hypoallergenic, or cleaning means. Sure, some (all?) chemical companies have had major problems. But a no-name brand that almost certainly buy all their ingredients from the same chemical companies has an awful lot to prove.  They'll have to show the science, engineering, and double-blind studies to convince me that they can do what they claim.

The longevity of consumer electronics and etc

Everything we buy gets thrown away.  99.9% of what your grandparents bought is gone, as is 99% of what your parents have purchased.  Most of it went into a landfill, or was burned, or recycled, or whatever. I'd say roughly 99% of what I bought before 2005 is gone. Sure, some of it is still around.  Most of it is gone, including the vast majority of consumer electronics.  All those CRT TVs, radios,  and early generation "flat panel" TVs are gone, with few exceptions. But here I want to predict and/or review how long stuff lasts.   Necessary Widgets  Let's assume for a moment that anything we buy is a necessity.  I know that's not true, but this is more of a practical thought experiment than an attempt to model a so-called "ideal". Obviously, a necessary widget that has a useful life of 10 years is going to produce half as much waste as a necessary widget that lasts 5 years.  Here I'm just going to list some things that I own (or have owned), and rate

The basics of fixing your WiFi problems

Here are the very basics: Restart your WiFi router Restart your router by disconnecting power from it for 30 seconds. Why it works: When a WiFi router is started, it chooses the clearest WiFi channel available.  But over time, neighbors could be moving their equipment around or buying new equipment, and your router keeps on using the same channel.  A restart forces the WiFi router to re-evaluate which channel is best. Centralize your WiFi router: Place your WiFi router centrally, both horizontally and vertically.  You might need longer cables to do this, or you might need to get creative.  Under the TV or against an outside wall is almost always the worst choice. Why it works: WiFi is a short-distance radio technology.  Distance and physical structures significantly weaken the signal.  Placing the WiFi router centrally shortens the distance, and will minimize the number of walls and ceilings and objects that the signal has to travel through.

Examity's Garbage Software Is Failing Its Partners

I was helping a friend install the "Examity SB" software for proctored exam taking. What a mess! I'm not complaining about the concept of the proctored online examines. It is the quality of Examity's client software implementation and associated process that is nothing short of an embarrassment. Examity's software and process design flaws can turn the test-taking process from "stressful" to "idiotic nightmare". "Examity SB" is one of the worst "professional", publicly distributed software packages I've seen in years. A Rant for the Ages. Adobe Flash? Please! First, Examity's website suggested that I download and install the obsolete Adobe Flash software system. Since Adobe Flash is dangerous from a computer security perspective and unavailable, I decided to download the native SB application. Just as a data point, my organization decided to sunset our use of Adobe Flash for user-facing pedagogical software developme

New Apartment, New Internet, and the Nightmare of Xfinity

Today is the day! I am "installing Internet" in a friend's new city apartment. The goal: great Internet service for a group of young professionals, while keeping the cost as low as possible and the reliability very high. Here is the story of what I did to accomplish that goal. The overview of the who, what, and where: Four professionals, mostly working from home. Very densely populated urban environment. Comcast Xfinity is the area's wired, high-speed Internet monopoly. High reliability and reasonable performance for video chat is critical. Internet Service Ordering: Don't Over-Do It. Let's say you want to reduce your daily commute time. Right now you drive a stock Honda Civic that costs $80 a month. How much commuting time will you save by investing $200 a month on turbocharger? Zero hours and zero minutes. "Gigabit" download speeds are an extraordinary waste of money. Sure, we'll have four people being busy all day, but busy does not mean there

The Recycling Symbol does NOT mean "curbside recyclable".

We've all seen the famous recycling symbol on products, like these: ♲♳♴♵♹ The Weird "Recycling Symbol" Surprise The "Recycling" symbol you see on packaging and products are NOT designed to have anything to do with curbside recycling.  Instead, the symbol is merely an indicator of what kind of material it is made out of. Industry plasters this symbol on many products that are to be thrown in the trash.  Industry over-applies this symbol as a "greenwashing" strategy, tricking consumers into believing that a product is recyclable when in reality it is not.  And Consumers are tricked: people WANT stuff to be recyclable, and so they throw it into the recycle bin.  Then the bad item gets blended into a bunch of other otherwise good stuff, and diminishes the entire lot. So what is recyclable?  The answer is: read your local recycling rules, and be a pessimist. If in doubt, it is better to throw it into the trash than to ruin an entire lot of recyclables. Befo

Various ways of powering the MikroTik hAP

I have several MikroTik RB952Ui hAP AC Lite routers.  They're located in closets, basements, attics, and on desktops.  Each location results in different needs in terms of power.  Happily, the hAP AC Lite is quite flexible when it comes to power.  Here I document the three different ways I have powered my MikroTik AC Lite routers. Power Solutions: Active PoE+ Splitter, Passive PoE Injector, and Standard wall adapter Standard Power: MikroTik (or aftermarket) Wall Wart The default way to power the AC Lite is by using its standard "barrel-style" power port, which is far more flexible than your typical router.  The AC Lite accepts power between 10 and 24VDC.  When using the MikroTik in a desktop configuration, I use the stock 24 volt MikroTik power adapter .  The stock adapter output specifications are as follows: 24 VDC 1200 mA  2.1mm barrel Center Positive  Passive Power-over-Ethernet solution: TP-Link Power Injector Sometimes it is useful to power the router without the p

My First MikroTik hAP Adventures

I recently upgraded my current home Internet infrastructure with a Mikrotik Routerboard router.  My legacy WiFi equipment had been based exclusively on 802.11n, which still works well but is now two generations old.  I decided to upgrade with a " MikroTik RB952 hAP AC Lite " router, in hopes that it becomes my "personal standard" for home networking. The MikroTik home router is small, inexpensive (under $50), and highly configurable.  It is reasonably modern, with an 802.11ac radio. It runs MikroTik's RouterOS operating system, which is comprehensive, frequently updated, and provides far more capability than I need.  It also seems to be possible to run OpenWRT on this router . I was using Apple Airport routers (easy, capable, reliable, but no longer manufactured) and GL.iNet's OpenWRT based routers (flexible and inexpensive, but mine were the 2.4 GHz only models).  They all served me well with no complaints.  I figured that now was the time to try something

Using a Directional WiFi Access Point - the TP-Link CP210

I have two buildings on my property, and I wanted to bring Internet to my garage without pulling a wire. Previously I was using the barely-adequate reach of my house's WiFi, but it was just a little too far and it would drop frequently enough to be painful. My solution is a WiFi Directional access point - the TP-Link CP210. I chose the CP-210 because it was inexpensive. It only supports the 2.4 GHz band, but my goal was quality over performance. In all, it does this job perfectly. I mounted the CP-210 in my attic because it was easier to install that way. If I really wanted to I could mount it on the outside, but that means drilling holes and climbing a ladder and other things that I don't want to do. After all, it works great from inside - an outside mount isn't going to give me anything more except more work. I simply pointed the CP-210's antenna to my garage and that was it. Easy and effective. The CP-210 has a bunch of useful configuration options - it isn't jus

My MacBook A1342 gets demoted.

I've been using my late 2009-vintage A1342 MacBook as my primary computer for many years,  but I have just upgraded to a 2020 "M1" MacBook Air . There was nothing wrong with my old MacBook, except that it could no longer run a supported Mac operating system.  So I decided to repurpose it as a utility laptop that I can drag around to different sites to perform basic network maintenance functions. My old MacBook had a Sandisk 1 TB SSD inside, which is far more than it needs now.  I ended up pulling out  the 1 TB drive and putting it into a USB3 enclosure so that I can archive bulky files on it (photos, email, videos and documents).  Instead of the 1 TB drive, I put a very inexpensive 60 GB SSD into the MacBook.  60 GB is plenty of space for what I plan to use it for. Thank you, MacBook A1342.  Your 11+ years of service have been amazing.

Making a GL.iNet Mini Router Mounting Bracket

I love my GL.iNet Mini routers, but one issue I have with them is that they are so small that they are hard to mount on a wall. Yes, I could buy a specialty bracket, but it seems like there is a faster and cheaper way.  Enter my solution: A home-made bracket that can be made in minutes using heavy paper or transparency film. A little cutting and folding and tape, and in minutes I have a reasonably robust router mount. Homemade GL.iNet Router Bracket Creating the Bracket The PDF document allows for four brackets to be created from a single 8.5" x 11" sheet of card stock. That's far less than penny for numerous brackets. Win! Here is the process after you download the PDF document: Print it on heavy card stock or on plastic film. Cut out the shaded areas with scissors or a sharp knife.  Cut on bold lines. Fold on the dotted lines Use some tape and/or glue to make a little box that you can tack or staple to the wall Bracket ready to be glued or taped together I find these

My good old Apple Airport Express N v2 and DFS.

For the past 7+ years I have been running the same class of WiFi equipment: The Apple Airport Express N v2. I have been exceedingly successful of running these routers.  They are rock-solid devices, and they support many more channels than the typical expensive "prosumer" routers, since the Airport Express supports DFS.  Why did the tech press slam the Airport Express as being "overpriced and under-powered"?  Because the tech press is filled with idiots. How awesome is DFS?  Let me tell you. I live in the city where there are 40+ visible WiFi access points in my vicinity.  Each of these routers are all trying to scream over one another to be heard. There are only really 6 or so non-overlapping WiFi channels (2.4GHz and 5 GHz).  Each of the standard channels have at least 5 visible access points. Except the DFS channels, which no one seems to use. So when I boot up MY Airport Express, it lands on Channel 52, where there is literally no competition.  My house gets the

The Privacy Disaster of Cloud Backup services

All "cloud backup" services encrypt data using industry-leading encryption algorithms so that you can trust that your data is secure. Except that's not true.  Although these companies do encrypt your data, the vast majority of these services keep a copy of your encryption key, which they can secretly use at any time to look at all of your data. Sure, these companies likely want to do the right thing for reputational reasons, but the same could be said for Equifax and CapitalOne and Experian and hundreds of other finance and healthcare companies that each spend hundreds of millions of dollars every year on their computer systems.  Just taking a look at data theft throughout the industry and we have to ask ourselves: WHY should anyone have confidence in a backup service that has full access to all of my data? To put the nail in the coffin, all these services have legalese that makes it clear that they are not responsible for any data theft caused by their failures.  They si

eBay and Free Shipping: Don't do it!

A lot of eBay sellers sell stuff with Free Shipping.  It is a bad idea. I don't believe in selling any of my items with "Free Shipping".  Why?  Because shipping costs very real money.  I can be more competitive with my pricing if my shipping expenses are lower. Here are the details: Shipping costs are based on distance.  Shipping costs real money, and shipping cost is almost always based on distance.  It is simply more cost efficient and fair if local people pay less and far away people pay more.  Are you 300 miles away?  You should pay less because my real shipping costs are less.  Are you 1800+ miles away?  Sorry, but shipping that far costs me more money.  I'll ship it to you, but you need to pay more to cover the shipping costs. Taxes.   Some areas do not charge sales tax on shipping.  If a product is $15 + $5 shipping, the customer pays tax on the $15 product.  In contrast, if a product is $20 with "free shipping", the customer pays tax on the whole $2

Making a laundry equipment pedestal platform on the cheap

My concrete basement floor is very uneven, and so my laundry washer and dryer were bouncing all over the place. I solved this problem by making an inexpensive pedestal for my laundry machines. This post is about how I designed and made my laundry pedestal. It cost me less than $25 to make, and took about 30 minutes to build. A pedestal has numerous benefits:  It gives the equipment a perfectly level surface to sit on. It raises the machines so that they are easier to access. If there is a basement flood, a pedestal raises the machines out of harm's way It is very inexpensive. I made mine for about $25 in materials. Laundry Pedestal Design My pedestal is basically a piece of 3/4 inch plywood with an underlying frame made of 2x4 lumber around it to give it some structure. Then I mounted robust adjustable feet on each corner. In order to easily adjust the feet while the platform was sitting on the floor, I drilled four holes in each of the corners, directly above the adjusters. These

General Procedure to save a water-damaged MacBook

Ouch, a watered-damaged MacBook!  Maybe someone spilled some water or other liquid onto the keyboard.  This is bad!  Immediate action is in order, with seconds to spare. This is how I address a water-damaged device.    TIME IS OF THE ESSENCE! If it still works, turn it off immediately! Make sure it is unplugged.  Don't plug it back in. Do NOT try to plug it in or turn it on again.  Really. Open it up.  This requires the appropriate precision screwdriver kit.  Don't have one?  Take it to a shop!  Do NOT use the wrong tools. Disconnect the battery Mop up any water with paper towels. Is there water everywhere?  Pull out the board and other components to do some further mopping up in the tight spaces. Put the parts, except the display and battery, in a slightly warm oven (maybe 90 °C, or 190 °F) for 4 hours to help encourage the drying of parts.  Water can get under components, we want to encourage that water to evaporate. Let everything cool, reassemble, and test.

Adding a Water Flood Sensor to my Vista-20p alarm system

My Honeywell Vista 20p alarm system is fairly comprehensive, but I want one more feature: an alarm that lets me know when my sump pump isn't working properly. Here is how I added one for about $8 in special parts.   I'm afraid of a flood in my finished basement. I'm fortunate - my basement sump pump system is already redundant, with two independent pumps and two outflow pipes. The primary pump kicks in when the water level reaches 6 inches, and if that doesn't work, then the backup pump kicks in when the water level reaches 7 inches.  The backup pump should never kick in unless the primary pump is having a problem pumping.   But there is a problem with this setup: I might never know if my primary pump has failed, leaving me with no redundancy.  I want to be informed when I have one (or god forbid, two) pump failures. My goal is to have my Vista 20p alert me when the sump's water level is ever beyond the point where my primary pump should have kicked in, alerting me

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