House of Hacks

Thursday, December 26, 2013

How to make an air lottery ball machine

Need an air lottery ball machine? In this episode I show how I approached the task of making a homemade lottery machine including what I did and why.

Other homemade lottery machines on YouTube:
Video this lottery machine was built for: Super-Minilypse Utah, USA (iStock drawing)

Playlist of other project overviews.

Music under Creative Commons License.
Intro/Exit: "Hot Swing" by Kevin MacLeod at
Incidental: "Awesome Call" by Kevin MacLeod at


Today at the House of Hacks we're going to look at making a lottery machine.


Hi Makers, Builders and Do-It-Yourselfers. Harley here.

One Thursday a while ago, my buddy Rich gave me a call. He asked if I could build him a lottery machine. I told him, "yeah, I thought we probably could do something." Then he asked if he could have it by Monday. It turns out he was responsible for organizing an event that had a limited number of slots. Of course they had more people interested in attending than they had slots available and he needed to some sort of drawing. He thought a corny, 70s style video would kind of spice it up. Make it a bit more interesting than just pulling names out of a hat and reading them. So I asked for a budget and told him I'd get back to him.

I first went online to search for places where I could rent something like this. That would have been the easiest, most straight-forward thing to do, particularly given the time constraints. But I didn't find anything so the next thing I looked for was something where somebody had done something similar. I did find one YouTube video and that's all I found. It was a pretty simple build and didn't really work too well. Since then I've actually found another one that worked very, very well. It was a little complex probably, particularly for the time frame I had; it looked like it was microprocessor controlled. Links to both of those are in the description below.

So this is what I came up with. I found a couple punch bowls the right size at Walmart; they're just plastic bowls in the party section.

For the output side where the balls come out, I found that the shielding tube that you get for fluorescent tubes that's designed to keep the glass from showering down on top of you if you shatter the glass, those tubes are the perfect diameter for ping pong balls. And so I just cut a hole in the top and hot glued this in.

For causing all the air to blow around inside I decided to use the blower side of my shop vac. Because the shop vac is so loud, we decided we probably didn't want it on set right next to this while we were filming so we got twenty foot piece of dryer duct; the exhaust vent stuff. And that stretches out and like I said I think it's twenty foot long if I recall correctly.

I cut a piece of wood and drilled a hole in it with a piece of screen over it that would fit in the bottom of the punch bowl where we also drilled a hole. And then I attached -- this is a union that's designed to connect two of these together. I just cut slits on one side and folded those tabs down and hot glued it to the wood.

Then on the other side where the vacuum blower connector has to go in I went to the plumbing aisle and found a rubber drain piece. I don't know exactly what it's used for but the inside diameter was perfect for the vacuum hose and the outside diameter perfectly fit inside a three inch PVC coupler. So I got a reducer that's the three inch to four inch reducer thing and hot glued the rubber part inside here. And then this fit perfectly in the four inch dryer duct.

I hooked everything together and all the balls bounced around very nicely. We were really pleased with the way it turned out in the end. We did have to drill some holes in here and also in here to relieve some of the pressure. We found it was over pressurizing this and it tended to want to blow the assembly apart. But once we put enough holes in here it reduced the pressure enough that the balls bounced around perfectly and came out without any problem but we didn't have problems with it wanting to burst apart.

So, I'll put everything together and we'll take a look at how it works.


Thanks for watching. Please "Like" if you enjoyed this episode and here's a playlist of other project overviews like this one. Here at the House of Hacks we cover a wide variety of maker related topics. Subscribe if this interests you. Leave a comment or question below; I'd love to hear from you.

So, until next time, go make something. It doesn't have to be perfect, just have fun!

Tuesday, December 17, 2013

How to operate an old camera

In the follow-up to cleaning an old camera, I show how to operate the Graflex Series B. Then I reveal the results from the first roll of film through it in five decades after processing the film using the negative to digital conversion steps from a previous episode.

More about this camera:

In this episode of the House of Hacks I'm going to show how to operate this old Graflex camera.

Hi Makers, Builders and Photographers. Harley here.

In this previous episode I first showed this new-to-me camera that explained how the light travels through it and did a little cleaning on it. I mentioned in that video that I was going to be taking it out, run some film through it and report back on how it turned out.

I tried taking video out in the field but it didn't work out too well logistically so I'm going to do this episode here in the workshop.

Today I'm going to talk about the actual operation of this camera. I'm going to talk about how to load the film, how to set the exposure, both the aperture and shutter speed, how to take a picture and finally take a look at some of the first images out of this camera in over fifty years. If at any time you want to skip to a specific portion of this video, just click the appropriate menu item over here.

This camera model had available to it different backs. Each back took a different type of film which allowed you to change film types from one image to the next. You could also have multiple backs of the same type and put different types of film in them. This allowed you to shoot the same type of film but different varieties. Like black and white and color or different film speeds. Mine came with a carrier for 120 film which is really nice because 120 film is still made and manufactured. It's readily available. Amazon carries it. You can get it at your local camera store.

To start loading the film you move this little bar which frees up the carrier, the back to come off. This is what a 120 back looks like. To open this up you pinch these silver bars together and it just opens up like this. Inside here there's a film carrier, like so. There's a place for the supply reel. The film comes around here, this is what faces the shutter, rolls around and goes onto a take-up reel. The take-up reel, when a roll of film is finished, just free-rolls forever, like this. When you want to put in a new roll of film, you just manually click this over to the "S" position, you can hear that click, and now you're ready to load a roll of film.

So, we'll take this film out of the box. It comes in air-tight, light-tight packaging to keep the film fresh. There's a piece of tape here, you just break the seal across here. Sometimes it's easier said than done. Oh, this one just peel off, that's kind of nice. Different brands of film will do that a little differently.

The film goes in here, and it's just spring loaded, so you just put it in like so. You want to make sure this is in such that the film emulsion, the black part, is coming out from the bottom like this. This is so when it wraps around like this it's facing into the camera. It then rolls around and you put this little piece of flap in the slot like so and you just wrap it up. See how that slipped out? I've had that happen before. You want to make sure that when you start rolling this that it's actually engaged. There's nothing more frustrating than to think you've shot a whole roll of film only to open this up and find it's still at the start. There we go. Once we have it loaded on about one roll like that we want to put it back in here like so. And then we want to roll this around until it gets to "1." It stops when it gets to "1" and this is now -- put it right back on the back of the camera. The camera is now loaded with film and ready to shoot.

Exposure is made up of three things: film speed, aperture and shutter speed. This is commonly called the exposure triangle. We're going to talk about how to set this on the Graflex.

First, film is measured in ISO units that typically have values of 100, 200, 400 and so forth. Kind of powers of two. In digital cameras you can change this on the fly from one image to the next and you can also have partial settings on the ISO numbers between those power of two numbers. With film, each roll of film has a specific value and so once you put a roll of film in the camera that's what you have to work with until you take that film out. On the Graflex this is a little bit different because the backs are interchangeable so if you have multiple backs you can put different film in each back and change the backs from one image to the next, if you so desire.

The second leg of the exposure triangle is the aperture. This controls how much light comes through the lens and is measured in units called f/stops. Each f/stop either doubles or halves the amount of light coming through the lens. The larger the number, the smaller the hole and the less light that comes through but the greater the depth of field. On the other hand, the smaller the number, you get a larger hole that lets more light through but you have a shallower depth of field. The aperture blocks off this light with vanes that are controlled by either rings or levers that outside around the lens. Different lenses have different ranges. This particular lens opens up to f/5.2 and closes down to f/22.

The last leg of the exposure triangle is the shutter speed. This controls how much of the light that's going through the aperture actually makes it through to hit the film. In most cameras, there's a dial that you turn to set the shutter speed to what you want it to be and the camera just takes care of the rest. The Graflex however is quite different. It has a long piece of fabric in it with four different slits in it of different sizes. This fabric is rolled up on rollers that are then attached to some springs. The spring can have variable tensions set on them. So to set the shutter speed, you look on the side of the camera on a chart that has all the different shutter speeds on it. You find the shutter speed you want and read across to the left side to find the slit to use and read up the column to find the tension to use. There's then two controls on the camera that you set to these two values. To set the slits value, first of all make sure this lever is in the down position. That puts the mirror down and also engages the latch for the winding mechanism. Next, wind this knob until the value that's indicated by the chart shows up in this little window. If you find you've gone too far, you can use this release lever to back up to previous settings. To set the tension value, simply turn this knob on the bottom of the camera. If you find you've gone too far, you can back up by pressing this little release knob.

To determine the proper exposure values to use, you usually use a light meter. This is an older model that's very simple. It has a photosensor and a meter in it. The meter has a little red indicator on it. To use it, simply point it at the scene and rotate this dial to line up a green indicator to match the red indicator. You then set the film speed to match what you have in your camera and then directly read out on the chart here that tells you what shutter speed to use for which aperture you want to use. Very simple to use. Never fails. No batteries required. This is a newer version of the same thing. It's bigger. Requires batteries. But it also has a few new features. It does have a manual mode on it though so you can set the ISO on the film and find out what aperture and shutter speed to use to get a proper exposure. However, when I'm out in the field taking pictures, I'm always going to have my SLR with me and it has a built in meter so I just use it. I set it to manual mode, set the ISO to match the film I have loaded in the camera, and then center the needle on the meter by changing the f/stop and the shutter speed to be what I want it to be. I can then take a picture to make sure I have the correct exposure that I want in the camera and then I can just take those three values and apply them on the Graflex and be ready to go.

Once you have your exposure values, you're ready to make your image. The first thing of course to do is to frame and focus. I find it's best to do this with your aperture wide open so you can actually see what you're doing. Focus is controlled by this knob on the side which all it does is move the lens closer or further away from the film plane. To do both your framing and focusing, you use the viewfinder here on top and just look down through here, adjust your frame and then do your focus. Once all that's done, then you can dial in your aperture to what's appropriate for this particular image. Once all your exposure values are set, your shutter speed and aperture, you already have your film in there, you're ready to take your image. I find this works best as a four step dance. You just do each step right in sequence after the other without interruption. Step one is remove this plate from the film. This exposes the film to the inside of the camera. Two is to press the shutter release that's over on this side. Three is to put the plate back in. And four is to advance the film. I find that if I don't do this each and every time that I'll forget a [step] -- usually to either take this plate out, which results in no image, or I'll forget to advance the film, which results in double exposure, neither of which you really want. Once all the film has been used, it'll all be on the take-up reel; none will be left on the supply reel. Unlike 35 mm cameras where you reverse the film back into the canister, you just leave it on the take-up reel in this one. Take the back off to a darkish location, just like you used to load the film, open up the back, and on the end of the film will be a moisture sensitive adhesive. Lick that and stick it to the film. That'll keep it from unwinding, coming off the roll and ruining your film. Keep it in a dark location as you take it to your film processor for developing. And finally, take what used to be the supply reel that's now empty, take it off, put it in the take-up reel position and put in a new roll of film and you're ready to go again.

I ran a roll of film through the camera and took it to a local lab for processing and scanning. I had no idea what to expect since this is the first film that had been through the camera in over fifty years. I didn't know if it might have light leaks or some other problem with the camera that had caused it to fall into disuse. I received the scans via e-mail and opened them up and found them to all be identical. This was pretty surprising since I'd done exposure bracketing from one frame to the next and expected to have different exposures. I picked up the film in person a couple days later and sure enough they did have different exposures from one frame to the next. So the camera was working just perfectly. As it turned out, the scanner was in auto mode and it had adjusted the exposure on each frame to be what it thought it should be, negating the exposure bracketing I'd done. So, lesson learned is next time I need to have them turn off auto mode, if I've done exposure bracketing, in order to get the proper exposures on each frame.

I used the negative to digital conversion process I described in this video to get digital images that had the correct aspect ratio and exposure values. I'm very pleased with the way these images turned out.


I'll probably be doing more with this camera in the future. I may even do some developing if I do a lot with it.

If you have any questions or comments, leave them in the comments section below. And subscribe if you're interested in maker related videos. And here's a play list of other photography related videos that I've made.

Until next time, go make something. It doesn't have to be perfect, just have fun!

Monday, May 13, 2013

How to clean an old camera

In this episode, I clean my recently acquired Graflex camera in preparation of shooting some film with it.

More about this camera:

On this episode of the House of Hacks, I'm going to try cleaning up this really old camera.

Hi Makers, Builders and Photographers. Harley here.

On today's episode I'm going to do a brief overview of this camera and then we'll start cleaning it. I'll start with the outside, move to the lens and finally do the viewfinder.

A number of months ago, my Dad gave me a bunch of old cameras and this is one of them. It's a vintage 30s or 40s Graflex RB series B camera. It's a SLR and it was bought new by my maternal great-grandfather. My grandparents gave it to my Dad about the time I was born. I don't ever remember him using it or putting any film through it. I have no idea when the last was this was used. But, after I got it, I started looking at it and playing around, taking a look at it. The focus works. The aperture seems to work. The shutter release works. The film advance works. And so, I don't see any reason why this can't take pictures. I'm going to clean it up. It's been sitting in storage for who knows how many decades. So, it's dirty, but other than that it seems to be just in perfect shape. I'm going to clean it up; document the cleaning in this episode and in a future episode I anticipate showing the operation of it and some images that it makes.

An interesting things about the Graflex is it is an SLR. When we usually think of SLR, we think of something a little bit more modern where the light path comes through the lens, hits a mirror, up through a prism mechanism and then through the viewfinder. When the shutter is released, the mirror pops up, the light hits the shutter, the shutter releases and exposes the film or sensor. The Graflex is a little bit different. In its case, the light comes through the lens and hits a mirror, but then it bounces up and hits a ground glass plane. This ground glass gives you an image that's actually size for size the same as what the film will see. So, you can see exactly the framing you're going to get and the focus that you have. But again, when the shutter is released, the mirror will pop up, the light will come back, the shutter will release and the film will be exposed in the same way.

First I'm going to clean the outside with some compressed air, a terry cloth towel and some mild detergents.

Right now I have the lens in the down position to be able to focus and see through the viewfinder. This button on the side will cause that mirror to pop up. Now there's a clear path through the camera to the film. If we take the back off -- I have the shutter in what's equivalent in a modern camera to bulb mode, where the shutter's open. And if we look down through here we can see straight through the body with the lens on the other side. So, the only thing that we really need to clean in order to get the best picture possible is the lens. So, I'll tackle that next.

The lens comes in two parts. First is this outer part that just screws off. And the interesting thing about this is it has interchangeable lenses. This is kind of the standard focal length lens I guess you would say that's on here. And you can get another one that is more of a telephoto lens that was popular with portrait photographers. I'm going to use some 91% isopropyl alcohol and a lens cloth and clean this off, blow it off with some air and then we'll do the next half.

The second half of this lens contains the aperture and an objective behind it. If you look at this, it's kind of interesting. Modern lenses have between five and nine vanes in the aperture. And this one, I counted around and there is fifteen vanes. I'm not quite sure why there's so many more vanes on this versus a modern camera. I'm not quite sure the optics or physics behind it. I just thought it was kind of interesting. If we unscrew this I can get to the objective behind and this is considerably cleaner than the front lens was. With the aperture opened up all the way I can get to the front and obviously the back is no problem.

Well, that took a lot more elbow grease than I expected to get the front objective clean. It was really, really grimy. Much more grimy than I expected. The good new though is after I got the aperture mechanism apart, I realized the back objective actually screws in so it was much easier to clean the front part of the objective than I was expecting. So now I can put everything back together and move on to the next thing.

Since the camera is operational, really all I need to do is clean things up. If I look through the viewfinder here, we can see all these nasty black spots all over the place. For the most part this is just on the mirror or the ground glass. The lens wouldn't show up this way and that really the only thing that would impact the image quality on the film. So, while I have it open, I'll go ahead and clean this up, blow everything out and try to get rid of these spots just on general principles but they don't really impact image quality on the film itself.

So if we look inside here -- I have the mirror flipped down now -- if we look inside here we can see the mirror and the ground glass is up around the bend, we can't really see it too well. But we can see the mirror. I'm going to basically use the microfiber cloth and rubbing alcohol to clean the lens and I'm going to try to get up around the corner there on the ground glass as best as I can and blow it out with some compressed air.

Well, I think that's about all I can do for today. I think it's about time to button it up and I'll do a final test tomorrow when the sun comes back out. Cleaning the mirror was a bit more tricky than I expected it to be. It was in there deeper than I thought and it was just hard to get to. I wasn't able to get to the ground glass at all on the bottom. I was able to get to the top and that was probably the most grime that I've removed from the camera in any one particular area through this whole thing. Just kind of spot checking right now, as best as I can tell, it actually does look a lot better. I'll check tomorrow with another image; kind of an after shot from the before shot that I showed before to see how it really looks. But that's it for tonight. Time to button it up.

Well, that's what it looks like through the viewfinder now. It looks a lot better than it did before. I'm really pleased with the way it cleaned up. Amazingly, the dirtiest part of the whole camera, the part that got the most grime off of, was the top of the outside of the ground glass. That was just amazingly dirty and I think it made a huge difference on this particular image. The lens was also more dirty than I realized it was and took quite a bit of elbow grease to clean it off. But it's all nice, sparkly, shiny now, ready to go out and take some pictures.

That about wraps up this episode. I recently got a couple rolls of film and plan on taking the camera out this weekend to see how it performs. In a couple weeks, I should have a follow-up video going over the operation and see how the images actually turned out.

Thumbs up if you like this video and I'd love to hear from you if you have any questions or comments. Be sure to subscribe to find out about future videos.

Until next time, go make something. It doesn't have to be perfect, just have fun!

Saturday, April 20, 2013

Tool Review: Zoom H1 Accessory Pack

Review of the accessory pack for the Zoom H1.


Music credits: Hot Swing by Kevin MacLeod used under Creative Commons 3.0 (

What are fashionable Zoom H1s wearing these days? Find out on today's episode where we talk about accessorizing your Zoom H1.


Hi Makers, Builders and Do-It-Yourselfers, Harley here.

In the last episode, which I'll link right here, I did a mini-review and test of the new Zoom H1 I received. I didn't have time in that episode to do a review of all the accessory pack that came with that package deal. So, we'll do that in this episode. This accessory pack I bought as a package deal but you can also get them individually from Amazon and probably other retailers. But in this episode, we'll review each of the six items that comes in this accessory pack and see what it looks like.

First up, we'll take a look at the power, the electrical stuff. It came with a little adapter, an AC adapter. It runs off 100 to 240 volts AC, 50 to 60 her, so it'll run pretty much anywhere in the world. It does only have the spade connectors for the US. If you wanted to run it somewhere else, all you'd need is an adapter, you don't need an electrical adapter, just the physical adapters. The cable is just a standard USB cable. It plugs in one side to the Zoom H1 and the other side to your computer. Or to this device right here. All this will do is power it instead of using batteries. There's no charger in it so you can't put rechargeable batteries in it and charge it from this. So, really all this is good for is to run -- if you're on location you have power and you want to plug in and not use batteries. Other than that, for my particular purposes, this doesn't really do me much good. It is nice to have one more cable on hand to kind of clutter things up but again this is something that you don't necessarily need the accessory pack for if this is all you need.

The case is the next thing on the list. This is actually kind of nice. It's a padded case. It's not a soft case, but it's not a hard case either. It's kind of in-between. It does have a belt loop on the back that you use velcro to adjust or put on something besides a belt too I suppose. It's got a little hand strap that is -- it just kind of clips on here. You could use the hand strap for something else if you wanted or it can just snap on there. It does have two zippers that open up and, as I mentioned before, it has a little elastic strap in there, so if it was on your belt or hanging on something, it wouldn't just flop open. And there's a little space inside here, looks like it's probably to put extra memory chips in for extra storage. I don't think you could probably put batteries or anything in there. I'm guessing -- I can't think of anything else you'd put in there besides memory chips. This, and it is custom molded for the Zoom H1. This is probably one of the best parts of the accessory pack in terms of usability and something you couldn't get somewhere else.

Ok, this wind screen is another thing that probably only comes in the accessory kit. For my particular purposes, since I'm going to be using a lav mic most of the time, I don't know that it'll really help me much personally. But if you're going to be using it in this kind of configuration it probably wouldn't be a bad thing to have. I'll do a simple test here with and without the windscreen. So, first of all with:

Peter Piper picked a peck of picked peppers. Did Peter Piper pick a peck of pickled peppers? If Peter Piper picked a peck of pickled peppers, where's the peck of pickled peppers Peter Piper picked?

And now we'll try it without:

Peter Piper picked a peck of picked peppers. Did Peter Piper pick a peck of pickled peppers? If Peter Piper picked a peck of pickled peppers, where's the peck of pickled peppers Peter Piper picked?

And now finally for the two holders. First is this little tripod thingy. It looks kind of cute and all, but frankly it doesn't really work well. It's a little bit top heavy. The base isn't wide enough. The Zoom fits on here about like -- about this long. By the time you get it on there it just really wants to tip over. You can get it balanced so it sort of works but, yeah, I'm not terribly impressed with it. The Zoom is just a bit big for this particular tripod. If you're going to need something like this, my recommendation would be to get one of the small Gorilla Pods. I haven't tried it, I don't have one on hand, but just because of the way they're designed and their adjustability, I suspect they'd probably work a lot better than this does. This just doesn't have enough adjustability, it's not a wide enough base. The other thing you might be able to get some beanbags or sand bags to weight it down. That would probably help quite a bit. It's just the Zoom is too big and the center of gravity is just such that it doesn't really work very well.

In my unboxing video, I hypothesized that this little device was for holding the Zoom H1. I have since changed my mind on that. I've got some more clarity on it after reading the instructions. And I think what this is for is for putting it on a mic stand. After you've attached it in like that you can slide it into the mic stand and it holds it just fine. I think for mic stands that are tapered, where the clips are tapered, I think this would work just fine. I have seen some clips where they're parallel to each other for straight-sided micas. I'm not sure this would work all that well. It's always worth a try anyway.

So there you have it. That's all six items. Overall you have to decide for yourself if it's worth the twenty bucks, or in my case, ten bucks. Really, the only two things, well three things I guess, that you couldn't get somewhere else would be the holder for the mic stand, the case and the little foam padding thing. This isn't worth getting. This is only good if you're not going to run off batteries. And this you can get anywhere. So, these are the only kind of custom things in the box. You have to decide for yourself if it's worth it. For me personally, yeah, it's worth ten bucks, particularly for the case. I think the case is going to be the best thing for me out of all this. And then having extra cables is always nice.

That about wraps up this episode. I did recently notice that Scott over at The Frugal Filmaker has a episode on alternatives to things found in the accessory pack. If you find that interesting, I'll leave a link down in the description. Until next time, go make something. It doesn't have to be perfect, just have fun.

Tuesday, March 19, 2013

Tool Review: Zoom H1

Unboxing and initial review of the Zoom H1 digital recorder.

Links to USB charger teardowns:
  • Music: Hot Swing and Guiton Sketch by Kevin MacLeod used under Creative Commons 3.0 (
  • Sound effects: for free use
  • Photo: Zoom H4N by Mark Turnauckas used under Creative Commons 3.0


One man's toy is another man's tool. Regardless of what you call them, today we're going to open up a box of new toys... tools... whatever.

Hi Makers, Builders and Do-It-Yourselfers, Harley here. Today on the House of Hacks we're going to unbox and do an initial reaction to some new audio equipment.

All the videos to date, I've taken using the internal microphone on the camera. I've actually been surprised at how well they've worked. I've done some clean-up in post-processing and in the last video I actually did quite a bit. I was surprised at how well it turned out. But I did want to take it to the next level. So, in order to accomplish that, I got some new audio gear.

I looked at a number of models, did some searching and reading reviews and such. Based on my budget and what I had available, I ended up getting a Zoom H1, an accessory pack and a lavaliere mic.

The lav mic I got from Amazon and including shipping this was about $15. Try to get the box open here. The reviews were fairly favorable even in spite of the low cost. I'm sure it's not as good as a more expensive model but hopefully it'll be better than the built-in mic in the camera. We've got here a little instruction flyer, and that looks like that's about all there is to it. So, this kind of clips on here like so. It's obviously a mono microphone. And that's it for the mic.

The Zoom was available on Amazon and I did some checking around. I wanted to pay by PayPal and Amazon doesn't take PayPal so I did some more searching and found the same model available at B & H Photo for $10 more but it included the accessory pack. Normally the accessory pack is another $20 purchase. So it cost me a little bit more, shipping was equivalent, but I got all the accessories with it too.

In this package, looks like a plastic thing with an instruction manual and a micro-SD card and an adapter to be able to put into your computer for the regular SD card size. The Zoom itself and a battery that is not for retail sale. Probably just a cheap alkaline battery that won't last very long I'm guessing. That's pretty much it for the box on the Zoom. Not much in it but about what you'd expect.

And the accessory pack. I'm not quite sure what's in here. There's a picture on the back that we'll open up and see what it has in it. So, it has a cheap, well I don't know how cheap, an AC adaptor, basically just a USB thing. Based on some of the teardowns I've seen on some of these, I don't know if I'd really trust it. I might do a teardown on this as a separate project just to see how well built it is. Some teardowns I've seen, they're actually dangerous. Here's a windscreen that's designed to go around the whole top of the unit. And looks like a USB cable. Probably bog standard cable, USB A on one side and B on the other. Yeah, looks like the little micro side for one and the side you plug into the computer for the other. This is a little carrying case. Looks like some sort of vinyl case to store it in. It has a little belt clip on it. And a little hand strap. That's kind of nice, it has elastic on it so you can have it on your belt and it won't flop open. That's a nice little detail. This looks like some sort of stand. It looks like it has a 1/4-20 screw on one side, for like a tripod mount. I'm not sure how this goes together. Then there's a little mini-tripod, also with a 1/4-20 mount on it. This looks like it might be useful for things other than just the recorder. Little tripod, you could use it for a small camera too. I'll have to look at the manual see how this is supposed to be used. Oh. Maybe it's supposed to be used like a handheld thing. Yeah. I'll have to look at the manual on that one.

That's it. $10 more than this by itself at Amazon. I got this at B & H Photo. Seems like a fairly good deal.

Ok. So this is what came in the box. This was in the H1 package and this is all the accessories that came in the second package. I'm going to go set everything up and do some initial tests and report back.

Many consumer devices these days use a general purpose LCD graphic display for displaying information and a handful of buttons in order to navigate through a menu system and choose options and control the device. Zoom has chosen not to go down that route and I'm really impressed with the user interface on this thing. The front panel has a LCD display that is unique to this device. It's custom made and everything is displayed in a particular location for that particular function. The only other thing on the front panel is this single button you push it once to start recording and push it again to stop recording. It's that simple. They've made the basic primary function of operating the Zoom very, very easy and I really like that in this device.

On this side of the device there's a headphone jack or a line output jack; it'll work either way. There's a volume control. And the micro-SD card slot.

The top of course are the microphones. And it has this nice little protective plastic to keep the microphones from breaking. Some of their other models have the same configuration on the microphones but they don't have this plastic cover and I've heard reports that they have a tendency to get broken through accidental dropping and normal handling.

The bottom has a very tiny speaker that you can use for just basic monitoring. It's really low fidelity. You can't get a good read on good the quality is of the output because it's so limited by the speaker. But you can tell if you actually got what you were trying to get or not.

This side of the device is all the input functions. It has the microphone input or line input, either way. It has the manual input level controls if you're using manual gain control. It has playback buttons. Forward and back buttons for moving through files, or if you're playing back, it'll do fast forward and reverse to scan through the audio. The middle button is a combination of play and pause. And this button is to delete the file you currently have selected. Moving on we have the power button. You push it down and hold it to turn it on and then when you want to turn it off, you push it down again and hold it and it'll turn it off. You can slide it the opposite direction and it'll stay in that position for hold and, what that means is that all the other buttons are deactivated so you can't accidentally push something, change something, in the middle of recording. And then finally there's the USB connector for the computer.

On the back of the device there are three switches for options. There's a low cutoff switch that will, if enabled, will cut out low frequency noises such as air conditioners or traffic outside, that type of thing. There's the auto level control, you turn it off for manual control in which case the input levels will control the recording level. Or you can turn it on and it will try to figure out the recording level. Auto level control has never worked, it still doesn't work, for decades it hasn't worked, and it still hasn't been figured out and so the recommendation is to leave it off and always use manual control. And finally on the back there's the recording format. WAV for when you need high fidelity or MP3 for a lossy recording. But of course with MP3 you get much greater recording time on any given card. There's a 1/4-20 tripod mount so you can put this on top of a tripod or any other standard device holding mechanism. And then finally the battery connector. It takes a single AA battery.

So that's it for the overview. Beautiful user interface. I love it.

So now let's cover some of the real basic, simple operations of the Zoom.

To turn it on, you hold down the power button and after a second or two it comes on and it's ready to record at this point. You can see all the different functions on the screen and when you press the button it goes into record mode. And you can see it now starting to count up that says you're recording. You have the options of the bit rate it's recording at and whether the low pass filter is on or off. You can see the current recording levels, the battery status, all these nice and nifty little things. When you're done recording, all you have to do is push the same button again and you're done. It's that simple. It's really nice.

So, to do some of the option setups, they're on the back here. You've got the WAV and MP3 are the two primary things you'd probably be changing on a fairly frequent basis. For the WAV format, you switch it over to WAV and the forward and back buttons allow you to change the bit rate. Here you can see on the front panel it's 48k with 16 bit depth and you have 2 hours and 24 minutes of recording time on this particular SD card. If you press the button, it changes it to 44k and 24 bit depth and now it drops to an hour and 44 remaining. You can cycle through all the different options by pressing these buttons and seeing the changes in the record time. The same thing happens when you switch it to MP3 format. Now instead of having the sampling frequency and bit depth, now you simply have the standard bit depth settings for MP3s.The low is 48 kilobits per second and it will cycle all the way up to 320 on the high side and it also shows the recording time for each bit depth. So, you can kind of make a balance between the quality you need and the recording time that you need. You can see here 320 for MP3 format gives us over 11 hours of recording time on this particular SD card. If I switch it to WAV format we're down in the hour and 44 minute range; even less if we go up to 96k samples per second. At the highest density WAV format we have less than an hour of record time. So, MP3 format definitely does have a higher recording density.

The input jack is a stereo input but if you plug a mono microphone into it, it will only record on the left channel. Of course you can take care of that in post by duplicating the channel and putting it on both sides, but it is a limitation on here. You need an adapter for mono to stereo if you want to record on both channels.

When you're all done, you again hold down the power button until it says "Good-bye" and it turns itself off.

So that's it for real basic operation of the Zoom. Let's go over to the computer and see what it looks like when you connect it to the computer.

When you plug the Zoom into the computer, it comes on with the screen flashing between "Audio" and "Card." If you press the button when it says "Audio," it will appear to the computer as an audio source. If you press the button when it says "Card" then it will appear as an external drive. You can use the normal filesystem utilities, for example Finder on the Mac or Explorer on Windows, to manipulate the files on the Zoom. Typically you'd probably move them somewhere for further use. When done, you can simply eject the drive and disconnect it.

I'm going to read a short speech now and record it using both the onboard microphone on the camera and also the new lav mic with the Zoom and in post-processing I'll switch between the two so you can hear the difference and do a side-by-side comparison.

Four score and seven years ago our fathers brought forth on this continent a new nation, conceived in liberty, and dedicated to the proposition that all men are created equal.
Now we are engaged in a great civil war, testing whether that nation, or any nation, so conceived and so dedicated, can long endure. We are met on a great battle-field of that war. We have come to dedicate a portion of that field, as a final resting place for those who here gave their lives that that nation might live. It is altogether fitting and proper that we should do this.
But, in a larger sense, we can not dedicate, we can not consecrate, we can not hallow this ground. The brave men, living and dead, who struggled here, have consecrated it, far above our poor power to add or detract. The world will little note, nor long remember what we say here, but it can never forget what they did here. It is for us the living, rather, to be dedicated here to the unfinished work which they who fought here have thus far so nobly advanced. It is rather for us to be here dedicated to the great task remaining before us—that from these honored dead we take increased devotion to that cause for which they gave the last full measure of devotion—that we here highly resolve that these dead shall not have died in vain—that this nation, under God, shall have a new birth of freedom—and that government of the people, by the people, for the people, shall not perish from the earth.

As you can tell, the audio from this sounds much better than the audio from the beginning of this video. Overall, I'm pretty pleased with the way this turned out and looking forward to using it on future videos.

So, that's about it for this show.

Other than the unboxing, I forgot to say anything about the accessory pack. This video's already long enough, so I'll take care of that in another video.

Until next time, go make something, it doesn't have to be perfect, just have fun.

Sunday, February 10, 2013

How to fix a fluorescent lamp

In this video, I show the basic parts of a fluorescent lamp and how to replace the ballast.

More online resources:


Today in the House of Hacks, I'm going to try to fix the annoying buzz in this light fixture.

Hi makers, builders and do-it-yourselfers, Harley here.

I don't know if you noticed it or not in the last video, but there was a real irritating hum coming from this lamp fixture. And it got so bad as I was working in the shop over the holidays that I just turned the lamp off.

About fifteen years ago I installed four of these light fixtures and in the intervening years I've replaced all of the lights probably two or three times except for this one, probably four or five times. Each time I replaced it they work for about six months or so and then the light output dims down and they start humming until I just take the lights out.

Fluorescent lamps have been around since about the 1880s. They weren't commercially viable until the 1930s. It took this long to do the development of them because while conceptually they're really simple, you have mains lines coming in, going into a ballast, and then from the ballast, power going into the tube. Pretty simple, just two items. But from an engineering standpoint, what's going on in the ballast and what's going on in the tube, are fairly complex. Primarily, the ballast has to control a lot of details with starting the tube up. And then there's the physical design and chemical composition of the tube that's fairly complex also. So, while simple, they're also complex. That's why it took 50 years for them to go from research to commercially viable.

The purpose of the ballast is actually two-fold. First, it controls the rather complex startup of the lamp. And because of this complexity, there have been a number of strategies used over the years as fluorescent tubes have been developed. The second thing that a ballast does is simply deliver high-voltage, low current, alternating current to the tube to keep it running once it's been lit. For this reason, low voltage fluorescent lamps, like are found in RVs, and high voltage fluorescent lamps, like you might find in the shop, many times can use the same fixtures, the physical case, and the same tubes. The only difference is the ballast that's designed for different voltages to work from. But they all convert to the same output voltage for running the tube.

Interestingly, incandescent lamps start with a very low resistance and increases the resistance as they warm up. This creates a condition where it automatically limits the amount of current and keeps them from developing a short circuit. However, fluorescent lamps are exactly the opposite. They start out at a very high resistance and decrease resistance as they warm up. So, the job of the ballast is two fold. First of all it controls startup, warms the lamp up, gets it going. Then, as it does warm up, it decreases the current to the lamp to keep it from a self-destructive melt down.

There are two types of ballast: magnetic and electronic. The difference is kind of like the difference between a linear power supply, like you might find in a heavy component stereo amplifier, and a switching power supply, like you find in most consumer electronics these days. Older units like mine have magnetic ballasts. More recently, electronic ballasts have started to take over due to lower manufacturing costs and increased reliability. The rise of CFLs in the last decade or so is due in part to the development of these electronic ballasts.

The fluorescent tube contains a low pressure mix of mercury vapor and an inert gas, typically argon. The inside of the tube is coated with a mixture of phosphorus. The ballast creates and maintains an arc going through the tube. The arc going through the mercury causes an emission of ultraviolet light. The ultraviolet light is absorbed by the phosphorus which then turns around and emits visible light. This process of absorbing one frequency of light and emitting a different one is called fluorescence. Hence the term "fluorescent tube." And can be found in other places besides just lights. And finally the color temperature of the light is controlled by what other chemicals are mixed in with the phosphorus in that coating on the inside.

So that's a summary on the theory of operation of fluorescent lamps. A great resource online that has a lot more detail can be found at Edison Tech Center and I'll leave a link in the description below.

Since fluorescent lights are so simple, about the only thing that can cause this kind of constant failure is a bad ballast. So, that's what I'm going to replace in this fixture.

This is a new ballast I picked up at the big box store down the street. And this is an electronic version to replace the magnetic version that came originally in the lamp.

Before starting a project like this, if the fixture is wired into the circuit, make sure the power is turned off.

Or simply unplug the fixture if it's plugged in.

In this model of fixture, I have these little clips that hold the cover on. Some models have screws that you have to remove. But, in this case, all I have to do is a 90 degree turn and the cover comes right off.

Ok. I've got everything buttoned back up. The lights are in. The power is turned on. And we'll flip the switch and see what happens. Yay! They work. Brilliant.

That's pretty much it for this job. The proof will be in about eight months or so to see if the lights are still bright and the hum's still gone. But, I've done this before on other fixtures and it's worked pretty well. So I have pretty hight confidence that it'll work.

So, until next time, go make something. It doesn't have to be perfect, just have fun.

Tuesday, January 1, 2013

How to make soft jaws for a vise - Part 2

This shows some improvements to the wooden soft jaws made in part 1.


Hi Makers, Builders and Do-It-Yourselfers. Harley here with another episode here at the House of Hacks. Last episode I showed you how to make some soft jaws for the vise so you could clamp things without using the metal jaws on the vise to mar things up. This gives you a more resilient surface so you don't… if you have projects that are already finished and you need to put them in the vise, they won't get marred by the metal jaws. So that's the purpose of these. Last episode I just cut it out and we had a couple pieces of wood that fit in the vise. This episode we'll go through and I have some improvements to these, clean them up a bit and finish them off as a project.

If you didn't get to see last episode, you can click here and go take a look at it. At the end of that episode, like I said, we had two pieces of wood that just fit in the jaws here and you can clamp. Put something in here and they'll stay in place for you for the most part while you clamp something in here, just like so. This episode, one of the problems with this is they do stay in here but they're a little bit flimsy, they don't like staying in there really well. It's better than just pieces of wood that you have to hold in place. The first thing I want to do is add some magnets to this so they'll stay in place very solidly. In order to do that, we'll first go over to the drill press and drill some holes for the magnets.

I was accompanying my wife on some errands the other day and she had to go by the office store and I found these in the section where they have rubber bands and staples and paper clips and so forth. A couple packs of magnets. There's twelve of them in this pack, three quarter inches around and I don't know how thick but as I was looking at them, it looked like they'd probably fit perfect for this project. And when I got home, I found in fact they fit really, really well. They're thin enough that they're thinner than the wood. So what I'm going to do is bore a hole in the wood. I've got four marks put in here, all in the same place so they should all line up fairly well. I've set the depth gauge on the drill press so it won't go all the way through. Because we want it to be, the magentas to go below the plane, this plane so they won't cause it to rock on the vise. I think we're ready to drill these out.

Ok. I had a slight failure when I set the depth gauge. As you can see maybe from this angle, these two pieces of wood are a little different in thickness. I set the depth gauge for this piece so when I drilled out the holes on this one, they of course were shallower by the difference of the thicknesses of the wood. So the magnets fit perfect in this one, but they're a little bit proud of the plane on this one. I just reset the depth gauge and I'm going to do another pass at these to make them a little deeper.

Ok. So I'm ready to put the magnets in. I'm just going to five minute epoxy them in so they'll stay in and they'll never be coming out. One thing before I epoxy them in though, I've got four magnets here, and I've got them setup so that these two connect together nicely and these two connect together and then I also have it setup so that they go corner to corner and connect up. I'll show why I did that later in the episode, it'll become clear. But I'm just going to mark all these with a mark so I'll put the mark down when I glue them in and that way they'll all be in the orientation I want them to be in.

Ok. The epoxy's dried now and we're almost ready for the next step. I want to show you why I have the magnets arranged the way I did. It's so, number one, when the jaws are in the vise, the magnets are repulsing each other and so they won't stick to each other when they get close. They'll always be pushing away from each other to the other jaw. That's number one. Number two, for storage purposes, they clip together like that for nice compact means of storage. That's it for upgrade number one.

Upgrade number two, I'm going to drill a hole in here for hanging. We'll go over to the drill press and, it's just a simple hole. Ok, over here at the drill press I've got a quarter inch drill bit in here. That should be large enough for most nail heads and also if I want to put it on a peg board it'll be large enough for a standard size hooks that they have for those. I put a little mark here half way between this edge and this edge and half way between where the edge of the magnet is and the edge here. I'm going to come back just a hair so it's a little closer to the magnet to give me a little more wood on the top edge here. So, we should be good to go here. Just like so. Beauty.

Now that I have magnets in and the holes drilled for hanging it, the next step is, I'm going to put some paint on it, try to dress it up a little bit, make it look nicer. I'm not all that great at finish work and so I'm going to spend a little bit of time on it, just more out of practice than anything else. Sand it a little bit with increasing grades of sand paper to give it a nice smooth finish, some wood sealer to seal the wood before I put the top coat on it. Red. So that's what I'm going to do next. The next quote-unquote upgrade.

Ok, that finishes the first pass of sanding. Now I'm going to use some tack cloth here and wipe it down a little bit. Get all the dust off it from sanding. I realize I'm probably going way overboard on what I need for this little shop tool thing that nobody's going to see. But, you know, I'm of the philosophy that always do the best you can and small things like this work as practice for when your skills are really needed.

Ok. The next thing is to put on some of this wood sealer.

Ok. Going to let that sit overnight and dry.

I've got three coats of sealer now on the soft jaws. And I sanded with 320 grit between each coat just to try to smooth everything out. I think I'm now ready to put the color coat on it. So, I'll do one more final sanding with 320 just real lightly to cut the sheen and any high spots and then I'll paint it red.

I just put a final sand on it and wiped it down with tack cloth and I just created this little makeshift painting booth. This is the first time I've done anything like this, kind of see how it works out. I hung it on some wire, you can see it hanging here. And I put a hole on the top of the box and the idea is, as I paint, I can turn it to be able to get on the back side of it. We'll see how it turns out.

The makeshift painting booth idea worked really well. The box contained the overspray and the rotating wires worked to get on both sides of the object. So, overall I was really pleased with it. I did have two issues. First was, the box is a little bit on the small side and getting paint up underneath on the bottom was a bit tricky. The second thing was, when I first started, I had my two objects, the wire was bent a little bit closer than it is now and the objects, the magnets would sway together and cause them to click together, kind of like that. I had to pull it apart with the wet paint on there, clean things up, and it was really messy. I ended up spreading the wires apart a little bit and didn't have the problem anymore. Overall I would say it was a success and worked well.

The last thing I want to do to these soft jaws is put a silicone surface on it, kind of give it a rubberized jaws on it. Keep the paint from transferring to objects that it's holding and give it a little more soft jawness I guess. So, I ran into this product a couple months ago called Sugru. It's available online and I've used it for a couple projects. It's really cool stuff. It's a room temperature curing silicone putty. It's kind of like playdough from kindergarten. It comes in these sealed packets in multiple colors. This particular packet has five colors in it: orange, blue, green, black and white. I think I've used up all the black on other projects. But it comes in these little tiny packets and they're color coded. And there's a little instruction: seven steps to becoming a Sugru guru. Here's some green. I think we'll use green… actually this is black I think. We'll use black for these jaws. I think I have another one in here. White. Orange. Here we go. I don't know if I'll need one or two packets, so I'll open one and give that a try. The biggest downside to this stuff is it does have an expiry date. This says use by August and it's now a couple months after August. It still fells like it's ok to use. My guess is they're a little conservative on the dates. So, we'll open this up and hopefully it'll be good. Just cut this open… And there's just a little… Yeah, it still looks pretty good. Just kind of manipulate it with your fingers a little bit. It's a little bit on the dry side, but I think it'll still be pliable enough to work. You just kind of manipulate it a little bit to get it working well. In this case I'm just going to roll this out. It looks like I'm going to need two containers for this particular project. One for each soft jaw. I'm just going to kind of put this on here, about like so. You can use all kinds of different implements to form it the way you want it, to texture it the way you want it. I'm going to use an old ribbon cable from a old hard drive just to kind of give it some lines, texture in it. And we'll see how that works out. Try to get it fairly level and flat. And peel this off. That's kind of what it looks like. It's not a perfect job but we can kind of push this back a little bit. Square it up some. Like that. So now we'll just let that sit and I'll do the next one with another one and let it sit, let it cure, and come back to it in a little bit.

So I think that's about it for this project. The Sugru's about cured. It's been about ten hours and the packaging says it's three millimeters for 24 hours and it could probably go overnight and be a bit better. But it feels like it's pretty solid now. I really like this Sugru. I've used it on a couple projects now and it comes out really cool. It is past its lifetime though. This was definitely dryer and not as pliable to work with as it was for the last couple projects I worked on that were before the expiry date. So that's really the biggest disadvantage, particularly for me. You have to order it online and so you either have to have some on hand and risk having it go bad on you before you use it all up or you don't have it on hand and you don't have it when you need it. So, it's kind of a good news/bad news situation in that regard. I haven't quite figured out what I'm going to do with this long term as a product and using it in my hacks and stuff. So, I think that pretty much wraps up this project. It's nice and red and painted and I now have a clean spot, I'll have to redo my vise and get it repainted. It has a little hole to hang things up. Looks nice and has the silicone to buffer, give it a little padding. I'm pretty pleased with the way that turned out.

Until next time, go make something. It doesn't have to be perfect, just have fun.