House of Hacks

Saturday, April 22, 2017

Field trip to Salt Lake City Mini Maker Faire 2017


Description

Today at the House of Hacks, Harley leaves the workshop and heads out on a field trip to the 2017 Salt Lake City Mini Maker Faire. In this video, we walk around and take a close up look at some of the exhibits.

Salt Lake City Mini Maker Faire web site: http://slcmakerfaire.com/

For a written transcript, go to Field trip to Salt Lake City Mini Maker Faire 2017

Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Incidental: “Welcome to the Show” by Kevin MacLeod at http://incompetech.com

Transcript

Hi Makers, Builders and Do-it-yourselfers. Harley here.

Today I'm going on a fieldtrip to the Salt Lake City Mini Maker Faire. I've never been to one of these, Always wanted to go. We're going to check it out today. Let's go along and see what's happening.

[Video of various sights at the Faire]

Well that was it. There were probably about 30 booths there, give or take a few, that were roughly split between vendors selling things, organizations getting their name out in the community and people showing off things they made. It's kind of a good mix. Interesting to see the different things that are going on in the maker community here locally.

And until next time, go make something.

Perfection's not required. Fun is!

Friday, April 14, 2017

How to select a power supply


Description

A contact recently asked "How do I select a power supply for my project?" Once a project moves past the prototyping state using a battery, picking the power supply is a critical element of a personal electronics project. In this episode of House of Hacks, Harley discusses the four items to consider when choosing a surplus power supply.

For a written transcript, go to How to select a power supply

Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com

Transcript

What do turkey basters and power supplies have to do with each other? And why am I in the kitchen? We're going to talk about all this today at the House of Hacks.

[Music]

Hi Makers, Builders and Do-it-yourselfers. Harley here.

I was recently asked about selecting a power supply for a hacked together project. There are four things when selecting a power supply that you need to pay attention to.

The first two are simple. The last two are a little be more complex but not too bad.

First is the input, you need to make sure that your power supply is appropriate for what you're plugging it into. For the most part you're going to be using locally supplied power supplies, probably surplus stuff that you've scavenged, and in that case it's going to work because it's designed for your local environment. In the United States that's going to be 110 to 120 volts AC. Pretty much anywhere else in the world, with a few exceptions, it's 220-240 volts AC. So the first item, while it's there and you need to be aware of it, it's really simple.

The second item has to do with the output. Power supplies can either output volts AC, indicated by VAC or a squiggly line or it can output in volts DC, indicated by VDC or a straight line. And you need to select the type of current that's appropriate for your project. Most, if you're doing low-voltage stuff, most of those are going to be DC, but depending on what you're working on, AC may be appropriate for your case.

The last two items are volts and amps. And these are similar to properties of water systems so we'll look at that here in a minute with the turkey baster and the sink.

But in short, volts have to do with, kind of, the pressure that the electrons are pushing into your circuit. And you need to make sure that this is appropriately ranged for your circuit you're working with. Generally circuits have a minimum and maximum voltage. You need to make sure that the voltage coming from the power supply fits within those parameters.

And finally there's amperage. Amperage is more like capacity. So it has to do with, as long as your power supply meets minimum requirements for your circuit, you're good to go. Your power supply can provide more amps than you need, it just can't provide less. So, make sure you know what your circuit requires and your power supply at least meets that minimum.

For example, a circuit that requires 250 milliamps (ma) would work just fine with a power supply that supplies 250 ma, 500 ma or 100 amps. Any of those would work just fine. However, if the power supply says it's rated for 100 ma, that's going to be too little and your circuit won't work right.

So let's go look at the sink and see how water correlates to volts and amps.

OK. As I mentioned, volts have to do with the amount of pressure and amps have to do with the capacity.

If you think about a water system, there's a whole lot of capacity here. The city has probably thousands of acre-feet of water that are sitting behind these pipes. They can provide pretty much all the capacity that we need for our little simple demonstration here.

It also has a lot of pressure. We control the pressure by the knob here, the lever, and if we put this on here and we give it just a little bit. This would be like not enough volts where we have a really weak stream here and the circuit isn't going to work right because it just doesn't have enough oomph to make it work.

If we increase the pressure to just the right amount, we get a nice flow without overdoing things and we reach a point of equilibrium here where the equivalent of the circuit is going to work just fine because we have the right amount coming in, not too much, not too little and everything's going to work just fine. And this is kind of equivalent to the volts controlled by the lever here.

If we increase the voltage too much though, what we end up with is a lot of leaks. And when you have leakage in electronics, that's a really bad thing. Things tend to blow up, burn up, magic smoke escapes, all that kind of good stuff. So you really don't want to put too much voltage to your circuit. You want to have just the right amount of volts that you get a good flow like that without having too much.

But now in all these cases, regardless of how much voltage I had, how much pressure I had coming out of the circuit, I still had huge, huge, vast amounts of water sitting in reservoirs behind these pipes. And that's equivalent to your amps. Your circuit will only use the amount of amps that it needs, regardless of how much capacity your power supply has.

So in summary, there are four things to look at: the input voltage and current and the output current, volts and amps. Make sure that you have the sufficient volts within the range that the circuit is designed for and that you have at least the minimum number of amps that are required by the circuit and you're good to go.

Until next time, go make something.

Perfection's not required. Fun is!

Saturday, April 8, 2017

What is dielectric grease and why should I use it?


Description

What is dielectric grease? Why should I use dielectric grease? How do I use it? Dielectric grease is something used on automotive electrical connections. It is relatively unknown and has some misinformation floating around regarding it. In this House of Hacks video, Harley talks about the what, why and how of using it.

This is part of a collaboration with Mike at Tomahawk DIY. In his video, he shows how to change the brake light bulb on a 2005 Jeep Grand Cherokee.

With Tomahawk DIY, Mike is building a business dedicated to helping people Build Better Lives. A substantial portion of revenue is donated to organizations that focus on helping people build better lives in some of earth's most dire circumstances. Visit his About page to learn more about the mission of Tomahawk DIY and use this Amazon Affiliate link to help support that work: Buy Dielectric Grease.

For a written transcript, go to What is dielectric grease and why should I use it?

Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Incidental: “Beach Bum" by Kevin MacLeod at http://incompetech.com

Special effects: livingroom_light_switch by AlienXXX at http://freesound.com

Transcript

[Music]

Hey, I wonder if Harley knows his brake light is out. That could cause a real problem.

[Door slam]

Hey Harley.

Yeah.

Did you know your brake light's out?

No, I didn't know that. There's a car store right around the corner. Why don't we go get some parts.

Yeah, it's a really easy fix. I'll show you how.

Awesome. Sounds great!

[Buying parts]

Today at the House of Hacks, we're going to talk about replacing light bulbs and using dielectric grease.

[Music]

Hi Makers, Builders and Do-it-yourselfers. Harley here.

This is Mike from Tomahawk DIY and we're going to be talking about two things. One on his channel about how to replace a brake light and on my channel this videos going to be about what dielectric grease is and why you should use be using it.

In Mike's video, we put some dielectric grease in the fitting before putting in the new bulb.

In this video, I want to talk about what dielectric grease is and why we used it.

While shooting the bulb changing video, we ran into a problem that is a great example of why dielectric grease really should be used.

We'd taken the old bulb out, put the new one in and put the socket back in the tail light assembly.

When we tested it, it didn't work. After some checking, I found corrosion on the socket connectors.

Dielectric grease helps inhibit this type of corrosion.

If these had grease put on them at the factory, they wouldn't have corroded this way.

So what is dielectric grease?

It's a silicon based grease that is non-curing and non-conductive.

Coming out of the tube, it has a, well, greasy type consistency, and being non-hardening, it maintains this consistency.

It stays this way and doesn't get hard or setup.

Here I have the multi-meter here setup to measure resistance.

When I put a drop on the probes, we can see it is non-conductive until I press the probes together and they make metal-to-metal contact.

Bare metal will have a chemical reaction to the oxygen in the air, called oxidation or corrosion.

Oxidation is less conductive than the metal, causing the flow of electricity to be reduced.

If there's not much oxidation, the reduction isn't enough to cause a problem.

However, in the harsh, sometimes wet, environment of a car, oxidation can build up over time to be a problem.

At best, it will decrease voltage causing lights to dim and other devices not to work properly.

In extreme cases, it can cause increased heat as the current attempts to break through and cause plastic to melt, shorts and sparks and, in the worse case, a fire.

Dielectric grease does a couple things to help combat these problems.

First, it's an insulator and helps prevent arcing between air gapped metal.

In high-voltage situations, this can help reduce voltage leakage, like in the engine's ignition system.

But in the low voltage situation of lighting, this isn't it's primary benefit.

In normal use, any place there's air gapped terminals, the air is sufficient insulation.

It's primary benefit comes as a non-hardening sealant.

When it's liberally applied to an electrical connection, it coats the metal and surrounds the terminals.

But being squishy, it is pressed out of the way on the metal-to-metal contact points.

This creates a sealed electrical connection that prevents both air and water from getting to the metal.

Keeping the water out of the connector helps eliminate short circuits and keeping the air out limits corrosion from happening.

It also helps the plastic and rubber parts of the connectors.

The oils in the grease help minimize gassing off of the plastic's oils.

This in turn helps prevent the plastic from getting brittle.

It also lubricates rubber fittings to let them seal better but not fuse.

All these things combined make the connector easier to take apart next time the bulb needs to be replaced.

I've seen some more expensive cars with dielectric grease on fittings from the factory.

And I've heard of people who will go through their vehicle when they first get it and put grease on all the connectors.

Usually these are people who put their vehicles in unusually harsh circumstances, particularly off-road or marine environments.

Personally, I use it whenever I replace something, but I don't go out of my way to take things apart specifically to add grease to them.

But given this most recent situation, I may rethink that.

If this is your first time here at House of Hacks: Welcome, I'm glad you're here and would love to have you subscribe.

I believe everyone has a God-given creative spark.

Sometimes this manifests through making things with a mechanical or technical bent.

Through this channel I hope to inspire, educate and encourage these types of makers in their creative endeavors.

Usually this involves various physical media like wood, metal, electronics, photography and other similar materials.

If this sounds interesting to you, go ahead and subscribe and I'll see you again in the next video.

Thanks for joining me on our creative journey.

Now, go make something. Perfection's not required. Fun is!

Sunday, April 2, 2017

What entry level camera should I buy?


Description

Viewer JasonNevin asked what camera I recommend for an entry level photographer. In this video I give my reply.

Being shopping for a Fuji camera on Amazon. (Affiliate link)

For a written transcript, go to What is my entry level camera recommendation?

Music under Creative Commons License By Attribution 3.0
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com

Transcript

On the Canon 77D unboxing video, JosephNevin asked the question about what DSLR I would recommend for an entry level beginning photographer.

I'm going to give my, perhaps surprising, answer today here at the House of Hacks.

[Music]

Hi Makers, Builders and Photographers.

Before answering Joseph's question I want to, by way of full disclosure, kind of give a little bit of background about myself.

This is of course an opinion piece, opinion answer, and so in order for you to know how to weight my opinion, my answer, I want to give you a little bit of background about myself.

I grew up in the printing industry. My Dad was involved in the printing industry. My Grandfather had his own print shop.

And one of my earliest, earliest memories, when I was probably three or so... three or so years old... was of a camera. And so I've been around cameras my entire life.

When I was probably first or second grade I got this camera. It's a 35mm, kind of a point and shoot type deal as my first camera.

When I was in high school, probably as a freshman, I got my first SLR camera, right here.

So I've been around cameras my whole life.

I've been involved in the Canon ecosystem for the better part of a decade now. In our household we have four camera bodies, four Canon bodies and a whole bunch of different lenses and accessories for the Canon system.

I'm not a professional photographer but I am, I would consider myself a serious hobbyist.

I help out teaching classes a couple times a year with our local university extension course for beginning photographers and also people new to studio lighting and flash photography.

I have a significant background even though I'm not a professional.

Now having said that, with all the different cameras I come in contact with, I am partial to the Canon system.

I think it's probably the best system historically in terms of build quality, in terms of user interface, in terms of support and repair, it's just been second to none.

Nikon is probably a very, very close second and in terms of technology and feature sets, they historically have tended to leap frog each other.

So first Canon would be on top and then Nikon would come out with the next version and be slightly better and they'd just kind of leap frog.

Now having said all that, that's historical information.

In the last couple years the mirror-less systems have really taken the field by storm.

And in many ways I think that they have surpassed the Canon and Nikon system and Canon and Nikon simply haven't really kept up really very well, I don't think.

The latest releases from Canon have kind of been evolutionary improvements on what they had before but I don't think they're really keeping up with some of the innovations that are coming out in the mirror-less market from particularly Panasonic in their Lumix GH series cameras and Sony with their a7 something, I forget what it is, and the other A series cameras that Sony has been coming out with in the mirrorless systems.

Both Sony and Panosonic technically are I think vastly superior cameras to the current Canon/Nikon offerings.

Now having said that, I think both the Panasonic and the Sony systems don't measure up to Nikon and Canon in terms of service or in user interface.

I think Canon and Nikon both are better at positioning the buttons and how the menus are laid out, just kind of the overall user experience with their cameras.

Canon being just slightly better, in my opinion, than Nikon. Of course that could be more based on my own familiarity with the Canon system than anything really objective on that. It's purely a subjective opinion.

Now having said that, the Panasonic and Sonys technically, the image quality coming out of them, is far better than the Canon/Nikons I think.

So, what would be my recommendation?

If you're invested in the Canon system, if you're invested in a system, I would continue staying in that system. If you've got a bunch of Nikon glass or a bunch of Canon glass, just stay with that. Both systems are, have very solid offerings.

But if you're going in new, if I was going in new, didn't have any pre-existing conditions, I would be getting a Fuji system.

Fuji uses the Sony sensors, so they've got incredible, incredible images coming off those cameras.

But Fuji has the best user interface. It even surpasses Canon's, in my opinion.

A couple things that make it noteworthy is they have separate controls for the exposure triangle.

You have a separate knob for ISO, and for shutter speed and the f/stop is a ring on the lenses just like the old film cameras were. So everything you need for exposure is right there with a haptic feedback in a manual knob.

And I think this just puts it ahead of all its competition, across the board.

Also, Fuji has a great menu system. The menus are laid out in a way that's easy to access the things that you commonly access and the things that are custom that are more detailed are layered in a way that is easy to get to, that makes sense, and the options are comprehensible.

Sometimes the other systems, particularly Sony, Sony is awful at the user interface. The menus are terrible. And finding things and configuring a Sony camera is a very, very frustrating experience.

So, I was going in new, I would go with a mirror-less system, with the Fuji. Their build quality is excellent. The user interface is excellent and their images that they generate are fantastic.

So that's it for today. Until next time, go make something. Perfection's not required. Fun is!

Friday, March 31, 2017

Canon EOS 77D unboxing


Description

In this video, Harley unboxes a new Canon EOS 77D. Canon just released their new EOS 77D today and Harley picked one up to supplement the household video capability. This is a short video where he opens the box and shows what's inside.

Amazon associate links:
Canon 77D kit with lens: http://amzn.to/2nP98uJ
Canon 77D body only kit: http://amzn.to/2nP9jGp

For a written transcript, go to Canon EOS 77D unboxing

Music under Creative Commons License By Attribution 3.0
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com

Transcript

Today we're going to unbox a new toy.

[Music]

Hi Makers, Builders and Photographers. Harley here.

My wife just went on a trip taking our one video camera, other than the GoPro here, with her on this trip to shoot some video.

And she want to be doing some YouTube videos here in the near future so we're going to have some contention over the one camera that we currently have.

So today the 77D was just released, on the same day that she left, and so I went down and picked one up.

I figured it was probably a good camera that was... had a good value for the amount of money you have to spend in order to get some decent quality SLR camera and video capabilities.

So this is just going to be a simple unboxing video to see what's inside the box. This is a body only kit so there's no lens with it, it's just the body and a couple other accessories. So let's see what's inside.

Ok, opening the box...

we have a manual,

and a Register Now card,

and some other type of paperwork,

camera strap,

battery,

battery charger,

and the reason for all this... the 77D.

Pretty small. It's about the size I'd expected.

About the same size as my XTi. It has a whole lot more capability.

It's got video. It's got the popout screen. And so we'll see how it works out.

So, that's it for this video. It's really short, really sweet.

Tomorrow I've got to shoot some b-roll for another video I'm working on and I'm going to be using this camera.

I'm also going on a photowalk tomorrow evening so I'll be shooting some stills in the evening, night time, long exposure stuff probably a little bit and just kind of play around with it. See how it works out.

I'll have a video out in a little while after I've run it through it's paces and kind of get some first impressions of it.

Until next time, go make something. Perfection's not required. Fun is!

Monday, February 13, 2017

How to Make a Digital Valentine's Day Card


Description

Valentine's Day is tomorrow. Here's how to make a digital card to capture the heart of your sweetie. Well, OK, that might be overstating things a bit, but Harley does show an algorithmic way using trigonometry to generate a beating heart animation in an easy to use programming environment called Processing. This was inspired by a video LeiosOS posted last week.

The original inspiration: LeiosOS: Drawing a heart
Wolfram algorithm site: Heart shaped graphs

For a written transcript, go to How to Make A Digital Valentine's Day Card

Music and special effects under Creative Commons License By Attribution 3.0
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Incidental: “Carefree” by Kevin MacLeod at http://incompetech.com

livingroom_light_switch by AlienXXX at http://freesound.com

Transcript

Today at the House of Hacks we're going to make a high-tech Valentine's Day greeting.

[Music]

Hi Makers, Builders and Do-it-yourselfers. Harley here.

I recently ran across a new-to-me programming channel who's name I won't even begin to try to pronounce but I will link to in the cards and description below.

He did a video about drawing a heart where he used a bit of C code and his own graphics library.

I want to take his idea, expand a bit on why it works and show how to use the Processing programming environment to do the same thing.

First let's look at generating shapes...

Many people get overwhelmed by the thought of trigonometry with its sine and cosine, angles and other related things, but at its core, it’s really pretty simple.

Remember the old cartesian graph from math class?

It had an x-axis and a y-axis and points could be located on this graph using just two coordinates.

On this graph, let’s draw a circle with its center at the origin with a radius of one.

Now, let’s imagine a line starting at the origin and going through the circle.

We can draw this line at any angle from the x axis.

If it is on the axis it will be 0 degrees.

Regardless of where we draw it, it’s going to intersect the circle at only one place.

That one place will have an x and y coordinate that, by definition, is the value of the cosine and sine functions at that angle.

So, for 0 degrees, the place where the circle intersects the x-axis, cosine will be 1 and sine will be 0.

As the angle increases, the x value decreases and the y value increases until we get to 90 degrees.

This lies on the y axis where cosine is 0 and sine is 1.

As the angle continues to increase, the x and y values continue to change, always between 0 and 1, always on the circle.

And that’s the fundamental theory behind trigonometry, everything else is derived from this.

Now let’s plot these points a bit differently.

On the x axis, let’s plot the angle and on the y axis, let’s plot of value of sine remembering that sine is the y value on our original circle.

At 0 degrees, sine is 0 so we start at the origin.

As the angle increases, sine increases until we get to 90 degrees and reach 1, then it starts decreasing as we move into the second quadrant of the circle.

At 180 degrees sine is back to 0.

As the angle continues to increase, the y coordinate of our circle drops into the negative values in the third quadrant until it reaches -1 at 270 degrees.

Finally in the fourth quadrant, we see y coming back up to 0.

After this, the cycle simple repeats itself as higher angles are duplicates of the previous angles.

Now, doing the same thing with cosine, at 0 degrees, cosine is 1 since it represents the x value on the circle.

As the angle increases, x decreases to 0 at 90 degrees, -1 at 180, back up to 0 at 270 and finally 1 at 360 degrees, the place we started.

These functions are great for describing a lot of things that are periodic in nature, things that fluctuate between two values.

If we multiply the results of sine or cosine we can make these graphs fluctuate by a different amount.

For example, here’s the result of multiplying the sine by 2.

And if we multiply the angle by a value, the frequency of the fluctuation will increase or decrease.

Here’s what it looks like if we multiply the angle by two.

Things can get really wild if we start adding these two curves together.

Or subtracting them.

Or multiplying them.

Or doing anything else really.

Sines and Cosines are the basis for a lot of things in our modern world.

Today we’re going to see how they can be used to send a message to our sweetheart.

Processing is a programming environment that was developed about 15 years ago and designed to teach the basics of programming within a visual context.

Since it was designed with a visual context in mind, it’s great for experimenting with graphics and drawing things.

The Processing.org website has free installers for Windows, Linux and Macs.

Just download the installer and run it.

This gives us a a Processing environment that, once started, we can start writing programs in.

Let's look at a simple program to draw a circle.

We first define the size of our canvas, the color of our background and the color we want to draw in.

Then we’re going to define a variable to scale our circle by and an offset for the x and y coordinates.

These are needed because sine and cosine return values around the cartesian origin but the coordinate system of the Processing screen is based with 0,0 in the upper left corner of the canvas.

Then we’re going to define a loop from 0 to twice PI, going in small increments.

We used twice PI here because in computers cosine and sine typically use what are called radians instead of degrees as their inputs.

This is just fine though because there’s a one to one mapping between degrees and radians where PI is 180 degrees and two PI is 360 degrees.

Inside the loop we set x to the cosine value of the loop variable and y to the sine value of the loop variable.

Then we’re simply going to plot that point, offset and scaled by the previously defined values.

Let's save our work at this point.

When we press the arrow button in the top tool bar, our program runs and we get this nice circle.

Now that we have the basics of creating a circle, how’s this help us with our Valentine Day project?

A web search for “heart drawing formula” leads us to the Wolfram site that has a number of different formulas for drawing a heart shape.

The sixth one in particular lends itself well to the program we have for drawing a circle.

All we have to do is change the assignments to x and y to get something that looks like a heart.

One of the cool things about the Processing environment is it works well for animating things.

If we put the statements before the loop in a function called setup they will get called one time when we run our program.

Then if we put the loop inside a method called draw, it will get continually called over and over again.

But because we’re drawing the same thing over and over, it's not going to be too exciting.

So before running this, let's add a line to change the scaling each time the draw method is called and adjust a control parameter to keep the scale between a couple values.

Finally, move the background call from setup into draw so it happens every time draw is called. This will clear our canvas each time.

Now let’s run this.

Ah, a nice beating heart.

This is cool and all, but it’s hard to show our special someone.

By adding a line to the end of our draw method, we can tell Processing to save our drawing to a file.

Now let's run this for a little bit, stop it and go look at where we saved our program.

We can see a bunch of individual snapshots of each frame of our animation.

In one last step, we can go to Processing’s Tools menu and select Movie Maker.

It gives us a dialog where we can select the directory containing the shots of our animations and press the Create Movie button.

This compiles our individual images into a MOV file that we can e-mail to our intended.

[Music]

If this is your first time here at House of Hacks: Welcome, I’m glad you’re here and would love to have you subscribe.

I believe everyone has a God-given creative spark.

Sometimes this manifests through making things with a mechanical and technical bent.

Through this channel I hope to inspire, educate and encourage these types of makers in their creative endeavors.

Usually this involves various physical media like wood, metal, electronics, photography but sometimes other things, like programming.

If this sounds interesting to you, go ahead and subscribe and I’ll see you again in the next video.

Now, go make something. Perfection’s not required. Fun is!

Sunday, February 5, 2017

How to replace an Apple MacBook Air's dead battery


Description

Replacing the battery on Apple Macbook Air is really simple and only requires a couple minutes work. In this episode, Harley shows the couple steps needed to change the battery in an mid-2011 MacBook Air and restore it to its original capacity.

Rechargeable batteries have a finite lifetime, wear out as they’re used and need to be replaced. Unlike PC laptops, MacBook’s give a warning when the battery approaches end-of-life and needs to be replaced. Applications like CoconutBattery give additional information.

Purchase battery kit on Amazon (Associates link).

More about the pentalobe screw.

CoconutBattery website

For a written transcript, go to How to replace an Apple MacBook Air's dead battery

Videography by Rich Legg

Music and special effects under Creative Commons License By Attribution 3.0
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Incidental: “Mining by Moonlight” by Kevin MacLeod at http://incompetech.com

livingroom_light_switch by AlienXXX at http://freesound.com

Transcript

Rechargeable batteries wear out over time. MacBooks will give a warning when their battery is approaching their end of life and won’t hold a charge. Today at the House of Hacks we’re going to see how easy it is to replace one of these aging batteries.

[Music]

Hi Makers, Builders and Do-it-yourselfers. Harley here.

If you like to make things out of items such as wood, metal and electronics, subscribe to the House of Hacks channel to get notified of future videos.

My buddy Rich’s 5 year old MacBook Air, of mid-2011 vintage, started acting a bit strange. Instead of going to sleep when he closed the lid it started hibernating. And then, because it was hibernated, rather than coming on instantly when he opened the lid, it took a number of seconds to wake back up. And then he finally got this "service battery" warning.

After calling the local repair depot and finding it was going to be a week or so to get it replaced, and with an upcoming photoshoot in a couple days where he really needed it, he asked me to fix it for him. He got a new battery off of Amazon and brought it to the shop to get it replaced.

This particular MacBook’s battery is model number A1496 and it is available from a number of different vendors. Mac batteries are a bit more complex to replace than most Windows-based laptops, but they’re still not to too bad. Let’s take a look at the simple process.

First, for many models, Apple used security screws rather than the run of the mill straight or Phillips screws, so screwdrivers for Pentalobe screws, as well as the more common Torx, are needed for this battery replacement.

Fortunately, Rich purchased a kit that included all the screwdrivers needed to replace the battery. If you don’t get a kit with the screwdrivers, make sure you have the ones you need already on hand. These screwdrivers are not high-quality things you’ll use forever, but they are sufficient to get the one time job done.

After opening the kit, I used the Pentalobe screwdriver to open the bottom of the laptop. There are two long screws next to the screen’s hinge and short screws around the rest of the perimeter.

Once the screws are out, the bottom just lifts off, exposing the battery.

Now, there are 5 Torx screws that hold the battery in. They are at the four corners and one in the center. Again, the two next to the hinge are longer and the other three are shorter.

When the screws are all out, gently lift the battery up and disconnect it. The connector has a plastic tab to pull on. Gently tug on this straight back towards the front edge of the laptop. Do not lift up away from the laptop’s motherboard.

Putting the new battery in is just the reverse of this process.

Attach the connector and make sure it’s seated. Then place the battery back in place so the screw holes line up and replace the screws. Remember, the longer screws go next to the hinge. Be careful not to cross thread or over tighten the screws. They just need to be snug, not super tight.

And now might be a good time to blow some canned air around the fan and vents to make sure there isn’t any dust bunnies hiding around.

Finally put the bottom back on and replace the screws. Again, the long screws go next to the hinge and take care not to cross thread or over tighten them.

Turn the laptop over, and turn it on and admire your work.

If you use an application like coconutBattery, you can see details of the battery's status. This utility can take a snapshot of the status for comparison. Here we see the before and the after. The old battery was to the point where it only charged to 70% of what it was designed for. And we can see the new one goes to 100%.

The instructions that came with the battery indicated it should be discharged to 5% and then recharged to 100% several times in a row. I’m not quite sure why this is recommended. My understanding of the Lithium based battery chemistry is this isn’t needed. It may be a left-over remnant of a recommendation from the Nickel and Lead based battery chemistries or perhaps it’s to calibrate the battery’s charge controller. In any case, understand this is the recommended procedure.

And now this laptop is ready for another 5 years of service.

Join me in the comments below to let me know if you found this helpful.

If this is your first time here at House of Hacks: Welcome, I’m glad you’re here and would love to have you subscribe. I believe everyone has a God-given creative spark. Sometimes this manifests itself through making things with a mechanical and technical bent. Through this channel I hope to inspire, educate and encourage these types of makers in their creative endeavors. Usually this involves various physical media like wood, metal, electronics, photography and other similar materials. If this sounds interesting to you, go ahead and subscribe and I’ll see you again in the next video.

Thanks for joining me on our creative journey. Now, go make something. Perfection’s not required. Fun is!

Sunday, January 29, 2017

How to make a momentary latching switch


Description

A pair of momentary switches become a latching on/off switch as Harley expands on a previous video about remote controlling a shop vac. This is the first of several in a modular switching system to remote control shop equipment using the PowerSwitch Tail II.

The central part of this system is the PowerSwitch Tail. It contains an electronically controlled switch to turn things on an off. There are a large number of ways to control this. In this episode, we introduce a modular system to allow different types of switches to be used to control the shop vac (or any other type of appliance).

PowerSwitch Tail II (Amazon affiliate link)

How to easily make a low-voltage, remote shop vac switch

For a written transcript, go to House of Hacks: How to make a momentary latching switch

Music under Creative Commons License By Attribution 3.0.
Intro/Exit: "Hot Swing" by Kevin MacLeod at http://incompetech.com
Special effects: livingroom_light_switch by AlienXXX at http://freesound.com

Transcript

Last year I showed an easy way to remote control shop equipment using a PowerSwitch Tail, a couple batteries, a switch and some wire.

Today at the House of Hacks I’m going to show how I made a push-on/push-off switch that mimics the way a lot of shop equipment are controlled.

[Music]

Hi Makers, Builders and Do-it-yourselfers. Harley here.

Just a quick reminder, if you haven’t done so already, subscribe to the House of Hacks channel to get notified of future videos.

Last year I made a video responding to a comment by Rob about how I made the remote control switch on my central shop vac system.

In that video, I showed the core design element: the PowerSwitch Tail and how to use it with a simple battery operated switch.

Today i’m going to show a different way to control the same PowerSwitch Tail by eliminating the batteries and using a switch with two buttons: one to turn the tool on and one to turn it off.

This is similar to how many shop tools are controlled. It also has the additional feature of being able to be expanded upon in the future.

If you recall, the PowerSwitch Tail requires 3 to 12 volts DC applied to these two connectors to cause the tool to turn on.

Batteries are of course one source of power for this but they need to be replaced on occasion.
Since I didn’t want to deal with replacing batteries, in my application I decided to use a surplus wall wart style power supply. I had a bunch of these lying around and figured this would be a good application for one of them.

I plugged it into the same outlet I plug the PowerSwitch Tail into.

I connect the low voltage power supply to two connectors on an RJ-11 jack.

Then I connect the other two connectors on the RJ-11 jack to the two connectors on the PowerSwitch Tail.

This allows me to use a phone wire as an extension cord.

For the switch's end, I put another RJ-11 jack in a project box. This project box can now have any type of switch mechanism in it I want and provides a nice modular way to use different types of switches.

For example, I could put in a toggle switch just like I showed in the last video.

Simply wire the negative side of the power to the negative input on the PowerSwitch Tail and wire a switch between the positive side of the power and the positive input for the PowerSwitch Tail.

However, since we have power in the project box, we aren’t limited to just a simple mechanical switch.

We can build circuitry that controls the PowerSwitch Tail.

The first thing I’ve made is a simple latching switch.

Similar to the switches on many tools, like my drill press and my bandsaw, I press the green button to turn on my vacuum and push the red button to turn it off.

Inside the box is a simple flip flop.

A flip flop is a type of circuit with two inputs, called Set and Reset. It also has two outputs, called Q and bar Q, or also known as not Q. It’s just the inverse of Q.

The inputs receive momentary pulses.

If the pulse is on Set, then Q goes high and bar Q goes low.

If the pulse is on Reset, then Q goes low and bar Q goes high.

If we consider just one output, Q, we can see Set causes it to turn on and Reset causes it to turn off. It just flip flops between the two positions.

Flip flops can be made with a variety of different circuits ranging from discrete components to various types of integrated circuits.

I happened to have a Quad 2-Input NOR gate chip in my parts bin so I used that.

But I could just as easily have used NAND gates, a chip with a dedicated flip-flop circuit in it, or a couple of transistors and resistors.

Once I had the circuit built, all I had to do was put it in the box and wire it up.

The switches are wired with pull down resistors. This allows the inputs to be normally low and go high when the button is pressed.

The green button connects to the Set input. The red button connects to the Reset input.

The negative input to the PowerTail Switch goes to the negative power connector.

Since I’m switching the positive side of the power, I’m using a PNP transistor.

Its base connects to the flip-flops Q output.

The PowerSwitch Tail’s positive input goes to the transistor’s collector.

And finally, the transistor’s emitter connects to the positive power connector.

In this configuration, the transistor acts as the switch for the PowerSwitch Tail’s power.

When it’s all put together, pushing the green button turns on the appliance and pushing the red button turns it off.

Since this switch system is modular, I have plans to build other switches too.

The next one is a current sensing switch so the vacuum will automatically turn on when a tool is in use and will turn off, after a short time delay, when the tool is turned off.

I’d love to know in the comments below if the level of detail I presented here was too much, just right or too little.

If this is your first time here at House of Hacks: Welcome, I’m glad you’re here and would love to have you subscribe.

I believe everyone has a God-given creative spark.

Sometimes this manifests through making things with a technical or mechanical bent.

Through this channel I hope to inspire, educate and encourage these types of makers in their creative endeavors.

Usually this involves various physical media like wood, metal, photography, electronics, like in this video, and other similar materials.

If this sounds interesting to you, go ahead and subscribe and I’ll see you again in the next video.

Thanks for joining me on our creative journey.

Now, go make something. Perfection’s not required. Fun is!