I first came across the metal binder idea from Instructables. I then came across the traffic sign binder via Make. Having a middle schooler who can’t seem to keep a binder intact for longer than a week the metal binder idea appealed to me.

The Build

At first I was going to use sheet metal but came across an old STOP sign at a construction recycling center. The rest of the materials consist of a piano (continuous) hinge, a donor binder, and some rivets.

I used a Avery 2 inch heavy-duty binder because I wanted the heavy-duty 3-ring.

I cut the plastic off the binder so I could use it a template.

If you were curious - there is a difference between the cardboard used in the "heavy-duty" binder (bottom) and a standard binder (top). The cardboard from the heavy duty binder is stiffer and more dense.

Because the heavy duty binder is over-sized (compared to a standard binder) the STOP sign was not quite big enough. The back of the binder is missing it's corners. I think this add to the mystique.

I used a jigsaw (with a fine metal cutting blade) to cut the sign and the hinge. If I do this again I'll make a jig to help make the cuts straighter. A file and Dremel were used to dull the edges and corners.

I used a punch tool to make sure the holes for the hinge stayed centered while drilling

I riveted the sign and hinge together.

The final product.

I attached the 3-ring with screws rather than rivits, so that it could be replaced more easily if need be.

Final Thoughts

As mentioned before – if I make another one I’ll use a jig so that the cuts with the jigsaw are straighter. Also, as can be seen in the picture above, I used washers to makeup for the hinge holes being too big for the 1/8″ rivets. I have some doubts about how robust this will be. For now I’m going to see how it works but I may need to either use something else besides washers or track down bigger rivets.

We have a nice big freezer in our laundry room that we use to store overflow and other “deep freeze” items that we don’t (or can’t) keep in our kitchen freezer. The door on the freezer needs a good shove to get it to close fully and due to the sometimes absent-minded adults and kids in our house it has been left ajar more than once. In one case we had a near complete defrost of the freezer and the loss of quite a bit of food.

After Sandi found the freezer ajar again a few weeks ago I decided that I needed to rig something up to alert us when the freezer door was left open. After some searching I found a simple timer circuit based around the famous 555 IC. I used the timer circuit in conjunction with a Normally Closed reed switch to make an alarm for the freezer.

Video

In the video I completely mixed up the whole open vs. closed switch and referred to the reed switch as a Normally Open, it’s actually a Normally Closed reed switch as explained below. Also, I said that the buzzer was rated at 80dB, it’s actually rated at 100dB.

Schematic

Even when a schematic is available I like to draw my own. I find that it helps me understand the workings of the circuit better.

The circuit is simple, once power is applied (switch turned on) the green LED lights to indicate that the timer is counting down, once the limit is reached the green LED goes off, the red LED turns on, and the buzzer sounds. The duration is adjustable via the 100M potentiometer (variable resistor) between 1-10 minutes, it’s not precise but it works for what I need it for. With the potentiometer all the way down (no resistance) I got a countdown of ~27 seconds, which is about as long as I’d like the freezer door to be open. Perfect.

On Reed Switches

Reed switch contacts (click to make bigger). Image via: http://en.wikipedia.org/wiki/File:Reed_switch_(aka).jpg

Reed switches are really cool. In a Normally Open reed switch two contacts are aligned very close together in a glass vial, so close that when a magnet is placed near the reed switch, the contacts touch, completing the circuit and allowing current to flow. However, I needed the reverse, I needed a reed switch that completed the circuit (i.e. turned it on, let current flow) when the magnet was taken away from the reed switch. This can be done any number of ways but the simplest is to use just use a Normally Closed reed switch.

The whole Normally Open, Normally Closed thing can be a bit confusing. In the case of reed switches they are in their normal state when a magnet is too far away to have an effect on them. So a Normally Open reed switch does NOT complete a circuit when the magnet is removed, where as a Normally Closed reed switch DOES complete a circuit when the magnet is removed.

In any case I used a Normally Closed reed switch as I needed the circuit to be completed (the timer to be turned on) when the magnet was removed (i.e. the freezer door was left open).

The Build

Breadboarding (i.e. testing) the circuit.

The buzzer I used can run off 3-12VDC and is rated at 100dB at 12VDC, I’m not sure what the dB level is at 9VDC but it’s plenty loud enough to be heard even on the other side of the house.

I cut a piece of perfboard to fit in a mint tin and marked out where the buzzer and battery would go.

The perfboard where the battery sits was later removed because it made the battery sit to high, preventing the tin lid from closing completely.

A hole was cut in the tin to accommodate the buzzer.

The assembled alarm on perf board. I had to cut the knob on the potentiometer so that it would clear the tin lid.

Perfboard where the battery sits was removed to allow the tin lid to close fully. Ignore the extra holes in the tin...

The reed switch wires coming out of the tin.

I was not allowed to put holes in the freezer so I used double-sided tape to mount the reed switch and magnet in place. I used a hard drive mounting rail to extend the magnet so it was close enough to the reed switch.

I used a magnet from an old hard drive (which are super strong neodymium magnets) to mount the tin to the freezer.

The alarm mounted to the freezer.

The alarm works great, the reed switch is sensitive enough (the magnet needs to be within ~4mm to open the reed switch and turn off the alarm) that the door has to be purposefully closed in order for the alarm not to sound. The buzzer is loud enough that we can here it from any room in the house and when the freezer door is closed (which is most of the time) the circuit does not draw any power, so the battery should last a good long while.

Parts List

Posted below are a couple of videos of me testing a photo detector circuit that I’m making for a project. The circuit is based of the design by Rob Paisley.

FYI – The two videos were shot using my iPhone 4 – the first one is available in HD on Vimeo.

DANGER: This project deals with mains voltages which, among other things, can KILL you DEAD. If you choose to replicate any portion of this project I am in no way responsible for any adverse conditions that may result.

So, I have this vapor tight light fixture that I’ve wanted to make blink on and off, like a radio or cell phone tower signal light but was having a hard time coming up with a practical way to do it.

The main problem is that the light fixture runs off of 120 volts and I was not finding a practical cheep a way to control a mains voltage light. Sure I could use a DMX controller but that’s expensive and overkill. I found light socket flasher buttons (insert the “button” between the bulb and the socket and heat change makes the light blink) but those are old school, hard to find, wear out over time, and the flash rate is not customizable.

Of course I thought about using a microcontroller like my Arduino to control the light, but interfacing mains voltage devices with low voltage micro-controllers seems to be something a lot of people steer away from (the Arduino forums seem to be particularly against it). So, I was having difficulty finding circuit designs that would put me on the right path.

I finally came across this blog post which had a low voltage switching mains circuit; exactly what I was looking for.

Switching 120 Volts with 5 Volts (or less)

The circuit is really nice, it allows you switch mains voltage devices while keeping whatever low voltage trigger (e.g. a microcontroller) you’re using completely isolated from the mains voltage. I only made one change to the circuit by adding a 2200 uF capacitor on the low voltage side to help with flash timing:

The circuit was perfect, I only added a 2200 uF cap on the low voltage side.

The key component in this circuit is the MOC3020M, an opto-isolator/triac. What happens is when light from an internal LED (pins 1 and 2) comes on the emitted light causes a change the resistance between the internal triac (pins 6 and 4) allowing it to conduct. The internal triac on the MOC3020M is used to trigger a second (external) triac, in this case a 2N6073A, which is used to switch the mains voltage device.

By using an opto-isolator you break the physical (i.e. electrical) connection between what’s on the side of pins 1 and 2 (your low voltage trigger) and what’s on the side of pins 6 and 4 (high voltage device). The 2N6073A triac is used simply because it can handle larger loads (up to 4 amps if a proper heat sink is used) than the MOC3020M can handle on its own. I used a 2 amp breaker to keep the 2N6073A well away from its 4 amp limit for a couple of reasons: one, I don’t plan on using a 480+ watt bulb in the light (currently using a 25 watt) and two, I could not fit a proper heat sink on it.

With this circuit you can switch and mains voltage device with as little a 1.5 volts.

Making it Blink

I had originally intended to use my Arduino to control the blinking of the light, and though it works great and offers a lot of control options (variable blink speed, etc.) I decided to go a different route and use a simple LED blinking circuit because I just wanted the light to blink on and off and the Arduino (or other microcontroller) solution felt like overkill.

I decided to use a simple transistor based LED blinking circuit because I already had the parts for it, and it was relatively simple to modify the flashing speed to get what I wanted:

Notice that I used 1Mohm resistors instead of the 100k used in the original circuit. The two 1Mhom resistors along with the capacitors control the blinking speed. Lower resistor and capacitor values means a faster blinking rate. If you wanted to be slick you could probably use potentiometers in place of resistors to make the blink rate adjustable on the fly.

The circuit is designed to flash two LEDs back and fourth and is admittedly superfluous; a single LED flasher would have worked just fine. I decided though that I wanted to use the second LED as an indicator on the enclosure of the flasher circuit.

Instead of connecting an LED on the right side I connect the mains switch. The combination of resistors and capacitors that I used on the flasher circuit gave me a blink rate of nearly 20 flashes per minute from the vapor light. In case your wondering, 20 flashes per minute seems to be the slowest flash rate that the FAA permits^{(pdf – page 43)}.

Notes

• The flash rate is controlled by the two 1Mohm resistors and the capacitors on the flasher circuit. I had to experiment with various configurations of resistors and capacitors to get the flash rate I wanted. Using the two 1Mohm resistors gives you about 1.6 volts to the LEDs which is not enough to make an LED light up very bright but is enough to trigger the mains switch.
• The 2200uF capacitor used on the mains switch is not necessary but in this case is used to help get the flash rate of the light where I wanted it.

In Action

Build Pictures

Here is the mains switch laid out on a breadboard for testing. I tested that the circuit worked several times before connecting mains voltage to it.

The flasher circuit laid out on the bread board. The tape on the left transistor is there to identify it as bad (I fried it during testing).

The mains switch in its final form.

The flasher circuit in its final form.

I hadn't really worked out enclosures for everything before starting the project. I finally decided that there was enough room to put the mains switch inside the vapor light's junction box and run a cable out to control it.

I cut a piece of acrylic for the mains switch to sit on when mounted in the junction box.

Belive it or not I managed to get everything to fit in the junction box, even the breaker. The red CAT5 cable (with the two orange wires) will connect to the flasher circuit.

The breaker is as much for safety as it is to protect the 2N6073A from being overworked since it does not have a heat sink. Since the junction box walls were a little too thick for the retaining clips on the breaker, I used a little hot-glue to help keep it in place.

Tip – I used a stepper bit/Unibit to drill the hole for the breaker. Stepper bit/Unibits are great for drilling holes like this, if you don’t have a set, seriously get yourself one. You will not regret it.

After stuffing everything in the junction box I tested it with the flasher circuit.

I used a CAT5 cable from the light to the flasher box so I could plug it in with an RJ45 plug. This way I can easily change what controls the light if I want. I used a barrel adapter for power so I'd have the option to use a wall wart; here it's powered by a 9v battery pack.

Mains Switch Parts List

Flash Circuit Parts List

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

Brief History

V1 of the iPhone Call Recorder worked great but I found it suffered one issue after I published the post about it. I realized that the capacitors used to isolate the headphone and microphone needed to accumulate a bit of charge before they caused enough isolation to prevent talk back on the opposite end of the call. This meant that you needed to have a recording device plugged into the iPhone Call Recorder that puts out ~3 volts and both parties had to talk (to cause a charge to go through the caps) before the caps charged effectively. This really isn’t a big deal but I felt like it could be improved.

The [simple] Solution

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

I tried several other ways to try to accomplish what I was after but I mostly just ended up with a headache. From V1 this project was both incredibly frustrating and something that I just couldn’t let go of. What I kept coming back to was that the capacitors simply needed to be “pre-charged” but to do that required putting voltage into the system, not something I was keen on doing unless I could keep it from getting to the iPhone and the recording device.

The solution turned out to be quite simple:

Don't pay too much attention to this schematic... there are errors.

The design in pretty much the same as V1, except for the 9v battery, a couple 330 ohm resistors, an LED, power switch, and an additional capacitor. The battery pre-charges the two (primary) capacitors whilst an additional capacitor is used to keep the DC from passing out the recording output. The two primary capacitors isolate the mic and headphone (to prevent talk back) and also keep the DC from the 9v battery from getting to the iPhone. The 330 ohm resistor is used to knock the voltage down because having the full 9v going to the caps causes to much charge and completely blocks audio from the recording output.

The upshot to all this is that from the get-go the talk back problem is eliminated, even if you don’t have a recording device plugged in (or one that does not output voltage) there is no talk back. The one drawback is a slightly less punchy level on the recording output for the iPhone side of the conversation; I haven’t found this to be a big issue.

V2 Improvements and Features

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

• Improved talk back prevention – filter capacitors are now pre-charged via a 9v battery.
• Smaller (less fugly?) enclosure.
• Smaller and higher quality potentiometers.
• TRRS jack for iPhone compatible headsets – for instance you can use the ear buds that came with your iPhone to record a call.
• iPhone input is via a jack – Version 1 used a hacked TRRS cable coming out of the enclosure – this was inelegant and would make it difficult to repair if the cable was damaged.
• LED – ’cause LEDs make everything cooler.
• If the battery dies (or the switch isn’t turned on it functions the same as the V1 iPhone Call Recorder.

V2 Pictures

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

The following pictures are of a couple of V2 iPhone Call Recorders I made. The first one uses a small enclosure that is nice in that it has a battery compartment built in and is compact but its small size makes it difficult to work with. If you plan to make the iPhone Call Recorder V2 and you don’t have a lot of experience with electronics; I’d recommend using the alternate enclosure (noted in the parts table below) which offers a bit more room to work with.

This alternate enclosure is easier to work with than the one pictured previously. I like this enclosure better for that reason... and it's brushed aluminum and we all know brushed aluminum makes the world a better place.

Existing Options

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

Just to reiterate – Looking at my server logs I see thousands of Google searches related to recordign calls on the iPhone. I have no doubt that this is functionality people want built into the iPhone. People don’t want to have to use a bulky box and cables to do it, like me they want an app. Unfortunately, as far as I can tell there is no way for an app to be written that will record calls without the need for a third party (paid) service. It’s simply something that Apple hasn’t allowed, or for one reason or another, in their API.

There are two apps that I know of that facilitate recording calls on the iPhone – SpoofApp and Recorder 10:

• SpoofApp – In the time between my Version 1 Version 2 SpoofApp landed in the App Store and no longer requires a jail-broken iPhone. SpoofApp is a free app but you still need to purchase per-miniute credits in order to make any use of it. I briefly played with SpoofApp and it works well for recording outgoing calls.
• Recorder 10 – Available in the App Store for the low price of $0.99 but again, it only records outgoing calls and you have to pay per-min charge.
• Neither SpoofApp nor Recorder 10 lets you start a call recording mid-call.
• Both services require that your recorded phone calls sit on a third party server (privacy issue).

I would pay $50.00 for a native iPhone app that allowed on the fly recording of incoming and outgoing calls, saved the calls on the iPhone, and allowed for easy transfer of the recordings off iPhone. Unfortunately, it is my understanding that even if a developer wanted to, it’s not possible to interface with the iPhone during a call in such a way that would allow the recording of phone calls. For one reason or another Apple has not included APIs in the iPhone SDK to allow it. SpoofApp and Recorder 10 overcome this limitation by routing your call through a third party phone system which works, but has limitations.

Again, my solution is not perfect either, anything besides a native app is going to feel like a kludge. My solution is expensive, bulky, and requires basic soldering skills to make. However, it does surpass current apps in that it allows on the fly recording of incoming and outgoing calls and does not require you to pay per-miniute fees. It does what current apps can’t. Beyond the app I described, there is certainly room for improvement on a hardware solution, someone smarter and better equipped could make a hardware solution orders of magnitude better than mine.

DIY

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

I made a couple of V1 iPhone Call Recorders for people and a couple of V2s before publishing this and received dozens of requests for pre-made iPhone Call Recorders. However, most people lose interest really quickly when they find out it would cost them over a hundred bucks for one.

To be fair to myself, and the family I support, I have to charge for the time it takes me to assemble the iPhone Call Recorder. When you add all the costs up (parts, labor, shipping) a pre-made iPhone Call Recorder is expensive. For most I think this is a novelty item and they see some electronic bits thrown together by some guy in his garage (actually I’m in my house) and think it’s going to cost five bucks and get really sad when they find out it’s a lot more.

Besides that, It’s just not something I want to commit to at this point. I’d like to move on to other projects.

So, I’m not going to be taking requests for pre-made iPhone Call Recorders but what I have done is draw up a nice schematic and made a parts list complete with supplier links. I have tried to make it as easy as possible for you to get what you need to make your own iPhone Call Recorder V2. It does require that you have some basic electronics understanding and soldering silks (or a friend who does) but it never hurts to learn.

If you want to make one yourself, which I encourage you to do because making stuff is fun, I’ve posted a nice schematic and parts list with suppliers:

The Schematic

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

Here is the iPhone Call Recorder V2 Schematic drawn up in Visio [click to embiggen]:

For better resolution you can download the schematic as a PDF – here

The Parts

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

UPDATE – 04.26.2009: I have updated the parts list to reflect the parts that I use for pre-made iPhone Call Recorders and what I recommend you use if your going to DIY. The small black enclosure shown above is no longer listed because I recommend the larger (and easier to work with) aluminum enclosure. However, the part numbers for it and the custom perf board are: 546-1593PBK and 854-PR1593P respectively.

As always, if you have questions please leave a comment (preferred so others can benefit) or e-mail me at adam [at] awaitinginspiration.com.

If you make your own iPhone Call Recorder please, please, please, let me know and send me some pics.

Ok, there are a gazillion DIY digital picture frames out there, this is nothing new. I figure I’d share it though because it shows a good use for outdated hardware but it also serves as documentation so six months from now when I’m asking myself “how did I do that?” I’ll have somewhere to look.

A few months ago I acquired an iMac G4 Lamp (Apple officially designates it the “iMac G4 Flat Panel”), which these days is a pretty useless piece of hardware; especially if it’s missing the OS like mine was. However, even with the hardware to slow to be of any real use, I felt like it would be a shame dump it. The iMac G4 has a great 17″ LCD so I figured it would make a great digital picture frame. Since my G4 was missing the OS, I decided to use the PowerPC version of Ubuntu¹, and after some searching, testing, and cursing, I found that these instructions, with some tweaks to suite my needs worked the best.

EDIT: 3/24/2010 – Added missing step to install Samba, edited the fstab code to remove a space, and made note about Ubuntu version.

I won’t get into it here because there are already tons of HOWTOs (Google is your friend) but the first thing I did was to install Ubuntu Desktop.

NOTE: I originally set this up with Ubuntu 9.04 (Jaunty Jackalope) when I upgraded the Ubuntu install to Ubuntu 9.10 (Karmic Koala) something broke and feh refused to read pictures from the Windows share (despite is being mounted properly). I troubleshot the issue for a little bit to no avail and so decided to just go back to 9.04. Since this is not a production system (i.e. no used for anything but a digital frame) and has no access to the internet (blocked by firewall) I’m not worried about running an outdated version of Ubuntu. 9.10 may work perfectly fine and my issue could have stemmed from an in-place upgrade, not sure.

After Ubuntu was up and running I installed the image viewer feh by opening a terminal and entering:

sudo apt-get install feh

Like Vegard, my pictures are stored on another computer but accessible through a network share. I wanted to setup feh to display the the pictures stored on that computer; but unlike Vegard my frame will be connected to my network via a wired connection so I don’t need to mess with rsync like he did.

The first thing you want to do (if your pictures are stored on a Windows share like mine) is install Samba so that you can connect to it using cifs.

sudo apt-get install samba smbfs

That’s it no Samba configuration is necessary.

The second step is to create a mount point for the share. In a terminal I entered:

sudo mkdir /media/framepics

Next I edited the fstab config so that the share gets mounted to /media/framepics and stays persistent even after a reboot. Again, in a terminal I entered:

sudo nano /etc/fstab

This opens the fstab config in nano for editing. On the last like I entered:

//enterprise/phat_drive/data/pictures/imac_frame /media/framepics cifs username=yourusername,password=yourpassword,iocharset=utf8,file_mode=0777,dir_mode=0777 0 0

Note – the above code should be placed on a single line.

Here’s a quick explanation of the fstab edit:

The first part:

//enterprise/phat_drive/data/pictures/imac_frame

Is the UNC path to the share where the pictures are stored – enterprise is my server and the rest of the path phat_drive/data/pictures/imac_frame leads to the folder where the frame pictures will be stored.

The second part:

/media/framepics

Is the mount point I created, after the share is mounted I will be able to access the share from /media/framepics as if it were a local directory on the iMac.

The third part:

cifs

Is the file system used when accessing the share and as far as I can tell this is the best option; the share that’s being mounted is on a Windows box.

The fourth part:

username=yourusername,password=yourpassword

Is where I put the user name and password needed to access the share on the Windows server.

The fifth part:

iocharset=utf8

Is the character set used when accessing the share on the Windows server. Again, as far as I can tell from my reading this is what you want to use.

The sixth part:

file_mode=0777,dir_mode=0777 0 0

Is the file permissions set for the mount point – 0777 gives full access to the share from the iMac. Last two 0s are used to set the dump option and mount order, for this purpose 0 on both is fine.

Once the line was added to fstab I hit Ctrl X and answered Y to save the changes and exit out of nano. I then rebooted to make sure the share mounted properly after a reboot.

The next step was to set feh to start after a reboot, rescan the image directory periodically, and set the iMac to automatically turn the screen off at night and back on in the morning. I used the scripts from Vegard as a guide:

The first script is used to start feh:

#!/bin/bash
export DISPLAY=:0
feh --quiet --recursive --randomize --hide-pointer --full-screen --slideshow-delay 300 /media/framepics/ &

delay is the time in seconds that the image is displayed; in this case 5 minutes. /media/framepics is where feh will look for images. I saved this file in my home directory (you could stick it anywhere) as start-feh.sh and gave it execute permissions. I then went to system > Preferences > Startup Applications and added the script to the start up entries so feh would start automatically on boot.

The next three scripts are used in conjunction with cron to restart feh periodically and turn the screen on and off at scheduled times.

When feh starts it reads the images currently in the directory and will only show images that existed when it started. In order for newly added images to show I need to stop and restart feh periodically:

#!/bin/bash
export DISPLAY=:0
killall feh
feh --quiet --recursive --randomize --hide-pointer --full-screen --slideshow-delay 300 /media/framepics/ &

killall feh kills the feh process and the next line is exactly the same as the start-feh script. This script is also saved in my home directory as sync-feh.sh and given exicute permissions.

This script turns the screen off:

#!/bin/bash
export DISPLAY=:0
xset +dpms
xset dpms force off

This script turns the display on:

#!/bin/bash
export DISPLAY=:0
xset +dpms
xset dpms force on

They were are also saved in my home directory as screen-on.sh and screen-off.sh and given execute permissions.

The next step is to setup cron so that sync-feh.sh, screen-on.sh, and screen-off.sh run at set times. Form the terminal:

crontab -e

I added the following:

00 07 * * 1-5 /home/adam/screen-on.sh
00 09 * * 0,6 /home/adam/screen-on.sh
00 23 * * 1-5 /home/adam/screen-off.sh
30 0 * * 0,6 /home/adam/screen-off.sh
0 * * * * /home/adam/sync-feh.sh

The first line sets cron to run screen-on.sh at 7AM Monday – Friday.

The second line sets cron to run screen-on.sh at 9AM Saturday and Sunday.

The third line sets cron to run screen-off.sh at 11PM Monday – Friday.

The fourth line sets cron to run screen-off.sh at 12AM Saturday and Sunday.

Finally, the fifth line sets cron to run sync-feh.sh every hour, to refresh the images. Every hour is probably excessive but whatever.

I then removed the desktop background image and set the background color to black, removed the desktop icons (I had to use gconf-editor to remove the mapped drive icon) and completely hid all the panels. With the background set to black, the icons and panels removed, all that shows when sync-feh.sh runs every hour is a blank black screen.

¹ The PowerPC architecture is no longer officially supported by Ubuntu. However, it is still available and supported by the community.^↵

Image Source: oskay

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

8/26/2009 – I have seen some comments around some forums that this device is illegal. It’s not. It’s perfectly legal to make a device that enables you record phone calls and it’s perfectly legal to record phone calls to which you are a party of. However, depending on your jurisdiction, you may have to notify the other party that the call is being recorded. It’s always illegal to record a phone call to which you are not a party. Your mileage may vary, when in doubt do some reading, and consult a lawyer.

The Problem

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

I’ve wanted a way to record phone calls to and from my iPhone since I’ve had it but hadn’t really looked into solutions until a couple of weeks ago. What I really wanted was a native iPhone app that would record incoming and outgoing phone calls – there is SpoofApp but it requires a JailBroken phone, per-minute fees, and looks like it only works on outgoing calls. Another iPhone app Recorder 10, does not require a JailBroken phone but like SpoofApp you have to pay per-minute fees and it only records outgoing calls.

Exhausted after searching for something I assumed would be out there already, and finding nothing I figured that the only way I was going to get what I wanted was to do it myself.

I had a few criteria that I wanted to meet:

• Portable as possible.
• Record both sides of the conversation.
• The ability to start recording the conversation midstream.
• As little indication that the call was being recorded as possible.

Before I go any further – laws regarding the recording of phone calls vary from state to state and federal laws may apply as well. Don’t be stupid, do some reading and if in doubt talk to a lawyer. If you make this device and get yourself into trouble using it I’m not responsible. I’m also not responsible if you release the magic smoke from your iPhone.

The Obvious Solution

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

When you talk on a phone, whether you notice it or not, you hear a smidgen of your voice through the phones speaker. If phones didn’t do this it would sound strange when you talked on the phone. So my first test was to just record the headphone output [using a splitter] of the iPhone to see if I got both sides of the conversation. You can record both sides of the conversation like this but the iPhone side of the conversation is unacceptability low.

This is the method used by Rory but he uses the built in microphone on his Mac to record his side of the conversation. So, while Rory has a workable solution it requires the use of a computer so it’s not all that portable.

8/25/2009 – Previously I incorrectly stated that this method causes an echo on the recording but after going back and trying it last night I could not replicate this effect; go figure.

With this method you’re relying on the smidgen of audio that the phone feeds back to your ear piece. This is not enough to get a decent recording of your side of the conversation, which is why Rory uses his Mac's mic to record his side of the conversation.

Without using a second recorder (in Rory’s case his Mac) for your side of the conversation using this method your recording sounds like this. Notice you can barely hear my side (iPhone side) of the conversation and when it gets loud, you can’t hear my side at all.

A Better Way

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

So, I started to look at the pinout of the iPhone headphone jack which is a TRRS (Tip, Ring, Ring, Sleeve) jack. I stumbled across this post that gave instructions on how to wire a breakout cable so that you could use your own headphones and mic with the iPhone and after some dabbling I came up with this:

In this schematic the W, R, Y and NS (White, Red, Yellow, and Not Shielded) note the color of the individual wires for the TRRS cable I used.

Which, if you haven’t guessed already, does not work. Well, It actually does work. It records both sides of the conversation beautifully. The problem is that the person your talking to hears everything they say repeated back to them (delayed by a millisecond) in their ear peace, very loudly and very clearly. Not only would this “talk back” be very annoying for the person your talking to, it would defiantly indicate to them that something odd was going on with the call.

It seems obvious now but it took me awhile to figure out what was going on – to get the recorder to work the way I wanted, I needed to combine the headphone output and the mic input (my side of the conversation), to one single output that would go to the recorder. By doing this I ended up feeding the headphone output of the iPhone back into the mic input of the iPhone, which is why the person on the other end heard everything they said repeated back to them. The obvious solution was to not combine the headphone and mic to one output, but to record the calls I’d either need two recorders (one for each side of the conversation) or a recorder that had multiple inputs. I wanted to get it working using only one recording output.

I wondered if using a mixer would solve the problem and to test this I connected the headphone and mic outputs to my little Behringer mixer on separate channels and it worked beautifully. Unfortunately, as beautifully as it worked, it required the use of a small but not so portable mixer. So I consulted Google and found some schematics (link 1, link 2) for some simple two channel mixers. However, using simple mixer did not do enough to keep the headphone and mic separated, it helped but it wasn’t enough. Finally, by using strategically placed capacitors I was able to virtually eliminate the “talk back”problem.

The Solution

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

To keep things simple I combined the left and right headphone channels [see: Stereo-to-Mono Summing Box] to make a mono signal going to the recording output but the headphone output for the iPhone user (you) is still stereo. Also, you could probably use lower resistor values all around since the signal coming from the iPhone isn’t that hot but I decided to err on the side of caution for now. The potentiometers are your garden variety (Radio Shack) 100k audio taper pots; you could use 50k or probably even smaller with this setup and they only control the signal going to the recording output, which gives you some control of the recording levels.

Depending on the headset you use, you may need to modify the cable to have the headphones and mic on separate jacks; the one pictured here was made with separate headphone and mic jacks. Here I have the iPhone Call Recorder hooked up to a hand held voice recorder (which has a mic input) but you could use any recording device that accepts a 3.5mm jack.

Click here to listen to a phone call recorded using the iPhone Call Recorder.

Notes

There is a better way to record calls on your iPhone or any other Bluetooh enabled phone? Check out my review of the Call Mynah.

• It’s very likely that this is not the best (in fact it’s not), or the only way to accomplish recording phone calls on the iPhone, but it does work and it works well. I agree that the best solution would be a native iPhone app. but it’s my understanding that it’s not even possible to write an app. that records phone calls on the iPhone without using third party services like Recorder 10 and SpoofApp do (which they charge you for and are limited in functionality).
• As Gizmodo “journalist” Joanna Stern pointed out this is a “fucking ugly” solution. What she fails to note though it that it works and is in several ways it’s better than any of the software solutions available.
• While “Fucking Ugly” this solution does not require you to jailbreak your phone, you don’t have to pay per-min fees to use it, you can record both incoming and outgoing calls with it, your recording stays with you and is not on some third party server, it gives no indication that the call is being recorded, it lets you start recording mid-call, and it affords you the ability to use an external set of headphones and an external microphone even if you don’t want to record the call. In any case it’s certainly better than just rolling over and paying for an app. that does not do what you want/need it to do as “journalist” Joanna Stern suggests we all do.
• Despite “journalist” Joanna Stern’s assertion this is not a “switch box” it does not use any switches at all.
• I agree with everyone that it’s rather large but I used a project box that I had lying around; it could certainly be made to fit in a smaller box.
• Several people have asked “If you willing to go through the trouble make this breakout box, why not just jailbreak? It woudl be easier.” First, I have not jailbroken an iPhone, but based on my understanding of the process, I’d say that for me the amount of work between jailbreaking and making this breakout box is about equal. For someone less familiar with electronics this may in fact be more work than simply jailbreaking but you only have to make this breakout box once, by jailbreaking your iPhone your entering a never ending arms race with Apple (at least if yo want the latest iPhone OS). Also, the only app. that is available for a jailbroken phone that records calls is SpoofApp. SpoofApp seems like a great app. but as mentioned in the beginning of this post it not only requires a jailbroken phone, you have to pay per-min fees to record calls, only works on outgoing calls, and your recording ends up on a third party server that you have no control over; a privacy issue.
• You still get a little “talk back” but it is so mild that unless you were really, really, really listening for it you would not notice; it’s extremely mild. You actually have to blow in the receiver hard to get it to produce the effect.
• The headphones act as a microphone with this setup but it’s so weak that it has no effect on the recording.
• The headphone volume on the iPhone affects the level of the recording output.
• Obviously (or maybe not) this setup requires that you to use a separate headphone and mic during calls – you could just use something like this.
• The iPhone puts out ~3 volts on the mic line because it’s expecting an electret microphone. You could filter this with a capacitor but it probably won’t hurt anything. I’m assuming that I’ll always be using and electret mic so I didn’t add one.
• The TRRS cable I used was actually just a 3.5mm video cable. This type of cable comes with a lot of video and digital cameras. TRRS jacks and cables are surprisingly hard to find – Mouser does have a TRRS plug but I could not find TRRS jacks anywhere.

Build Pictures

UPDATE: There is a better way to record calls on your iPhone or any other Bluetooh enabled phone – Check out my review of the Call Mynah.

I needed a cheep and easy way to mount a computer under a table – some aluminum stock, Velcro, and bolts made for a quick and dirty mount for around $12.00.

The aluminum stock was bent to shape in a vice and 1/4" holes we drilled for the 1" bolts.

Velcro squares were used to keep the computer from moving around.

Rip-ties were used to keep the cables under control.

When swapping out the computer that my SmoothWall was running on I found that while the old one had a BIOS switch allowing the system to continue booting without a keyboard (the system runs completely headless) the new one, oddly, does not.

I found this method to make a keyboard loopback; but it did not work as the system seems to want to initialize the keyboard circuit. So, rather than have a full keyboard getting in the way I took the circuit out of the keyboard and put it in an Altoids tin.

The sacrificial keyboard.

The keyboard circuit in its new home - Used bubble wrap between the tin bottom and the circuit board and everything was hot glued in place.

All buttoned up.

Plugged in and working great. Fast, simple, and effective.

We have a utility pole in our backyard (previous owners had a trailer there) and it’s not that nice of a thing to have in one’s backyard (at least when it’s not doing anything). So your left with two options: take it out, or build something on it… guess which one I’d like to do:

FYI – Utility lines have already been removed.

Now, I’d like to build this for our boys (it would be great for Airsoft); but it can serve a second purpose – pull up the ladder and it would make a safe (at least temporary) shelter from the zombie hordes.

The main platform is 10x10 with the "deck" being 4x4. The utility pole is roughly 16 feet tall; the floor would be ~7 feet off the ground. Canvas would be used to enclose the sides completely - that way it can be rolled up to open the house for a 360° view.

The idea is to have to pole supporting all but the deck of the house.

I was tired of breathing solder fumes so I decided to make myself a fume extractor – in its simplest form a fume extractor sucks the soldering fumes up and passes them through a filter, in this case I used and activated carbon filter.

You can buy fume extractors from anywhere $30 to thousands but since I already had everything to make this (except the carbon filters and the tin) I decided to go the DIY route. The filters were $11 for a big roll (enough to cut a few dozen filters for this) and $3 for the tin.

Parts - small round tin, 40mm high speed fan, 12v wall wart, mini toggle switch, adjustable (gooseneck) lamp neck, carbon filter, and a pink pencil.

The tin I found (at Fred Meyer) had a magnet glued to it that had to be taken off.

The magnet peeled cleanly off.

Before I cut into the tin I drew out on paper how I was going to cut the fan opening.

I used blue painters tape so I could draw the cutout pattern on the tin. The darker lines get cut (used a Dremel).

Fan opening cut and mounting holes drilled.

I ran the power cable through the lamp neck.

I extended the leads on the fan and had to cut one corner off to get the fan to clear the neck bolt.

All secure - I had to scrap the toggle switch because it broke

I cut the carbon filters to fit inside the tin lid (popped out the plastic that was there). I found that layering two filters worked best for filtering while still giving enough air flow.

Works like a charm.

I can clamp it to the base of my PanaVise or anywhere else I may need it to suck fumes.

I needed a light for my “100 Things About Me” pictures and this idea has been sitting in my bookmarks for awhile.

So, I decided it was time to make my own and this is the result:

Taken using the Ring Light.

First "100 Things About Me" picture taken using the light ring.

My ring light was completely inspired by Joe Holst’s blog post on his own DIY ring light. Stop by his site and take a look at his – it’s much prettier than mine.

I have a 1U dual processor rack mount server that is particularly loud even sitting in a closed closet because (as is the case with most 1U rack mount servers) it uses several (4) tiny high speed fans to blow air through the case to keep it cool. Tiny fans like these can move a lot of air but have a habit of creating a loud high pitched whining sound when running and having 4 of them on, in addition to the two CPU fans, can be quite loud. Too loud.

I tried just unplugging the fans and leaving the top cover on but found that it got real hot, real fast. So, I left the top cover off and found that even with the tiny exhaust fans off everything stayed at a reasonable temp but I still wanted to move some air around to keep everything a bit cooler. If nothing else it was an excuse to “make” something.

What I tried was to hang a 120mm (15v) fan above the open server, hoping it would blow cooler air onto and push hot air away from the server. After I had the fan wired up and hung I did some tests to see if the hanging fan did any good:

Operating as designed – cover on, tiny fans running:

CPU1: 84.2°F
CPU2: 87.8°F
MOBO: 101.3°F

Operating with cover off and tiny fans unplugged:

CPU1: 118.4°F
CPU2: 124.7°F
MOBO: 131.0°F

Operating with cover off and hanging fan running:

CPU1: 102.2°F
CPU2: 103.1°F
MOBO: 113.9°F

So the hanging fan does help keep the Opteron processors away from their 156-158°F max operating temperature and it’s much quieter than the 4 tiny fans. It’s certainly not cooling as well as the 4 tiny fans with the cover on but it is acceptable.

The pictures are pretty self explanatory – just an easy way to get a computer up off the floor with supplies available at any home improvement store:

[click on images for full size]

My “Easy (and cheep) Panavise Weighted Base” post was featured on the Make blog! w00t!

This was an easy and cheap way to add a weighted base to my Panavise 201 Jr.

You can buy weighted bases that are specifically made for the Panavise 201 Jr; but I had the materials lying around and a lot of times making stuff is funner than buying it.

I used a 2.5lb plate weight (or dumbbell weight) for the weighted base. The only modification needed was the drilling of three holes for mounting the Panavise:

Introducing the Panavise to its new base:

Test fit – the screws will be trimmed later:

Screws trimmed and rubber feet added for grip and screw clearance:

All done; time for eggnog:

Related – Panavise Weighted Base on MAKE

WARNING: The following project deals with mains voltage, which can cause serious injury or death. Should you choose to replicate any part of this project I am not responsible for any injury or death that may result.

I wanted a way to easily and safely (or semi-safely) use my multimeter’s current measuring function (ammeter) on 120Vac devices.

To measure current with an ammeter you need to break the circuit and insert the ammeter so that the electricity flows through the ammeter on its way to the device being powered.

To do this easily and safely with devices powered via mains voltage (120Vac) I made this “interface.” One side of the circuit goes directly to the outlet, and the other is broken and goes to a terminal strip. An ammeter is connected to the terminal strip, completing the circuit and allowing the ammeter to measure the current being drawn from the device plugged into the outlet.

This was easy, took only about an hour to make, and all the parts can be picked up from any decent hardware store:

I started with a standard plastic surface mount switch/outlet box:

I used small angle brackets to attach the terminal strip to the box:

Drilled holes in the box to mount the terminal strip:

Cut some machine screws down to size:

The terminal strip attached to the box:

Drilled a hole for the wires to pass through to the terminal strip:

Wired up the outlet – this is wired the same way you’d normally wire an outlet except that one side (positive in this case) of the circuit is being broken by the terminal strip:

All together:

Only the last two terminals are used, the rest are just extra:

Measuring the current draw of a desk lamp (CLF bulb). Notice that I used longer screws on the terminal strip to allow alligator clips to be clipped on:

Now I can measure the current draw of a 120Vac device (or devices) easily and relatively safely using my multimeter. I say “relatively safely” because the terminals are exposed so caution should be taken when in use. Also, it should only be used for quick measurements, noting long term.

By measuring the current draw (amps) of a device you can easily figure out how many watts it’s pulling by multiplying the source voltage by the amps.

volts x amps = watts

My CFL bulb is drawing 0.12 amps, times that by 120 and we get 14.4 watts.

In my post “Framing a t-shirt (on the cheap)” I used an acrylic box frame to frame a t-shirt. The acrylic frame worked well but admittedly it was a bit haphazard and the masking-tape backing (which held the t-shirt in) was starting to come off. So while perusing the local Michaels for something unrelated I came across some shadow boxes and thought that they might work better.

This is the 8×10 shadow box frame I got from michaels, it goes for ~$14.00 but it was on sale for ~$9.00; either way it’s still inexpensive. Notice how tall the sides are – you will see the benefit of this later on.

A piece of foam core was cut to fit inside the frame:

The foam core was then placed inside the t-shirt and test fitted in the frame. Note that you may need to cut the foam core a little bit smaller to compensate for the t-shirt:

The high sides of the shadow box frame allow the rest of the shirt to be stuffed inside the frame:

Before the final fit a lit roller was used to remove any fuzzes from the t-shirt:

Gave the glass of the frame a good cleaning too:

After the final stuffing the the back of the frame was put in place:

Final result:

This project reached featured status on instructables and has received over 8,000 views there. It was also listed in the instructables “Weekend Builder” e-mail!

This is an easy and cheap industrialish picture/poster frame I came up with a while back – it uses 1/8″ thick 3/4″ wide flat aluminum stock and some little alligator spring clamps; all of which you can pick up at Home Depot and the like. I’ve used this on larger (20″x30″) pictures but here I’m showing some smaller prints, whatever the size the method is the same.

Parts:

• 4′ of 1/8″ thick 3/4″ wide flat aluminum stock | Home Depot, etc.
• Alligator spring clamps | Home Depot, etc.
• Parts cost – ~$13.00 | enough to do 3 8″x10″ pictures

The picture that is being framed is a slightly modified version of this iStock vector illustration.

Cut the aluminum to size – they need to be as long (or wide, depending on orientation) as your picture. These pieces will be placed on the top and bottom of the picture, so measure accordingly. I used a miter box and a hack saw for the cutting:

All cut:

After cutting the aluminum to length it’s a good idea to file the ends, to get rid of any burs:

Clean the aluminum – I used a special aluminum cleaning chamber but you could get by with a bathroom sink, soap and water:

To add some rigidity (so it does not slouch) to the hanging picture, we’ll use foam core board:

Measure and cut the foam core so it’s the same size (maybe slightly smaller) than your photo:

Next, we prepare the clamps. The ones I got from Home Depot have a neon green plastic cover that I removed:

Leatherman to the rescue:

The only thing left is to do is clamp the aluminum, picture and form board together:

Note: I’ve found on larger pictures I’ve had to glue the picture to the foam board using spray adhesive for best results.

Related – Framing a t-shirt (on the cheap) REDUX

Related – Framing a t-shirt (on the cheap)

This project reached featured status on instructables and has received over 24,000 views there. It was also listed in the Instructables “Weekend Builder” e-mail!

If putting holes in the wall was a game this shelf wouldn’t net you any points. The image above is a very rough SketchUp drawing of a shelf I am going to start building over the next couple of weeks. The concept of “clamping” shelving between the ceiling and floor isn’t original to me, in fact I’ve see several variations of the idea; this is just my variation. The point of this method of mounting shelves is – you get the shelf without the holes in your wall, the concept also lends itself to being placed where there is no wall (stud) support.

If you want it you can download the SketchUp file

2/8 – flanges arrived yesterday, build starts Friday night.

First step is to remove the lip from the 9 flanges that will be used to support the shelves:

If you don’t want to remove the lip yourself Simplified Building will bore out the flanges for you (additional cost for each fitting).

The following action likely voids any guarantee or warranty the Kee Klamps have.

There probably are better ways to do this, but I used a metal hole saw to remove the majority of the lip and then a drill grinder to get the rest out:

The flanges were screwed down to the board to keep them secure during drilling:

The hole saw didn’t quite remove enough of the lip, so a grinder was used to get the rest out:

Eventually:

Testing the fit:

Cutting the pipe to length:

3 short pieces for the ceiling half of the clamp mechanism:

3 long pieces for shelf support and floor half of the clamp mechanism:

Taking the burs off the ends of the pipe:

3/8″ thread rod, bolts and washers for the clamp mechanism:

This is how I originally envisioned the clamp assembly, this later changes slightly:

Making the holes in the shelves for the pipe to pass through:

Test Assembly:

Notice the change in the clamp assembly from the first picture? I decided that the pipe in the ceiling half of the clamp assembly wasn’t necessary:

Emily, the child labor my niece helping to sand the shelves before the application of polyurethane:

Final assembly, I found the easiest way to assemble the shelf was to insert the pipe into the footer and slide on the flanges and shelves separately adding the header last.

I was sick out of my skull while doing this part, apologies for the lackluster photos.

Making everything level:

The bottom shelf got a hole on either side to pass cables through:

All done:

This was an easy project, the hardest part of the build was drilling out the lip on the flanges; so Kee Klamp take note and make flanges that allow the pipe to pass through Simplified Building will do this for you. Admittedly, I was worried as to how well this shelf would work (even though I’ve seen similar shelves before) but the shelf turned out to be very stable. Even though it’s placed against a wall here I don’t think there would be any issues if it wasn’t.

Project parts:

• x15 – type 61-6 1″ Kee Klamp Flanges | Simplified Building
• x3 – 10ft 1″ galvanized pipe | Home Depot
• x3 – 1x12x8 | shelves | Home Depot
• x2 – 1x6x8 | header and footer | Home Depot
• x3 – 2ft 3/4″ threaded rod | clamp assembly | Home Depot
• x6 – 3/4″ bolts | clamp assembly | Home Depot
• x6 – 3/4″ flat washers | clamp assembly | Home Depot
• x60 – 3/4″ screws | attach flanges to shelves | Home Depot

Notes:

• Galvanized pipe is dirty because of the oil that is on it, you’ll want to clean it off after cutting it to length, dish soap and water worked well.
• The Home Depot grade of galvanized pipe may not be “pretty” to some people. You could use aluminum pipe or prettier galvanized pipe but it’s a bit spendy and I like the industrial look; fence post is probably to flimsy for this project.
• The table saw and metal cutting blade I used worked but it binds easily, a chop saw would work better.
• You want to tighten the clamp mechanism pretty tight, just not too tight as putting a hole through your ceiling would defeat the design of this shelf.
• I didn’t cut the 2ft threaded rod, about 1-1/2″ is inside the top flange the rest is inside the pipe. You want to make sure that there is a decent portion of the rod in the flange and the pipe to alleviate the possibility of it slipping out.

In the interest of full disclosure – Simplified Building provided me with a discount (read: I still paid for them, just not retail) on the Kee Klamp fittings used in this project. In exchange for the discount I agreed to document the project here on awaitinginspiration.com and instructables.com. This project was conceived and planed using Kee Klamps and would be using Kee Klamps purchased from Simplified Building regardless of the discount Simplified Building graciously extended me. Thinking about it, I got off like a bandit because I’m not doing anything I wouldn’t have done anyway.

Related – Kee Klamp Shelf (not on the cheap)

Jim Blumenfeld sent me an e-mail detailing his customized Denkimono Alarm Clock/Timer kit.

from the e-mail:

Thought you would enjoy the attached pictures of the Denkimono clock kit. I’ve been working with them on custom programming for my specific application. The next spin of the PCB board will have more mounting holes and provisions to connect to the PIC to change the programming. I’ve designed mine for use in timing high speed off road car rallies. The Red button freezes the time of day to record the time the car crosses the timing line. I took the connector with the 90 degree bend and straightened the pins and used that to stack the boards. It is also powered by a 6 volt sealed lead acid battery and has a simple voltage regulator on board to allow it to be run from a cig lighter plug in a car and to also charge the battery.

Thanks Jim!

Related – Denkimono – alarm clock/timer kit

photo goodness: (click on image for full size)

Because people don’t already know I’m a Geek – this is what I went as this past Halloween.

The Geiger counter, which I found while browsing The Electronic Goldmine inspired the costume. I started with the Geiger Counter which (as disclosed by EG) was broke to begin with. I added blue LEDs on the gauge in place of the needle and used a sound-to-light module to activate the LEDs when the sound from a record/playback module played a looped Geiger counter noise through a speaker.

I bought the gas mask from eBay ($9 I think) and wired in a green LED light bar from SparkFun to light my face. Also, a mic was wired inside the gas mask which ran to a voice changing module. The voice module was wired to a speaker that was attached to the outside of the suit, with it I could change the pitch of my voice from very deep to very high and robot style.

I used washer drain hose and attached it to one filter port of the gas mask to run the wires for the LED bar and the mic in to the control box. An additional hose was attached to the mask and then to a fan box to blow fresh air into the mask.

The Geiger counter was powered with 4 AA batteries for the record/playback module and a 9v battery for the LEDs. The mask LED bar and voice changer were powered by two 9v batteries (wired parallel – I was paranoid about the batteries dying). The suit fans and the fan light bars were powered by 12v sealed lead acid batteries (I used two wired in parallel – again paranoid about battery time, this was overkill). The sealed lead acid batteries were carried in a backpack that I wore inside the suit, the fan boxes and the speaker were velcroed to straps of the backpack to help support them.

There were two fans for the suit, one blew air into the mask via a hose and the other blew air directly into the suit. An unintended but welcome consequence of the fan blowing into the suit was that it inflated it adding a comic effect to the whole thing. I was somewhat surprised at first since it’s only an 80mm case fan but it’s a Panaflo high speed so it does move quite a bit of air. I can’t stress enough that ventilation was very important, this was a real Level B chem suit, it’s like being in a human size Ziploc® – without the fans I would have passed out. In reality a suit like this would be used with a SCBA (self contained breathing apparatus) but since those are probably like a billion dollars I opted for the fans. All in all it worked out pretty well, it was hot and I sweet like a pig but I was able to stay in it as long as I needed to – then went home and took a shower.

Supply list:

• Geiger counter -The Electronic Goldmine (I can’t find them here anymore but you can find them on eBay)
• Gas mask – eBay
• Level B chem suit – Spill 911 (cheapest I could find)
• Blue LEDs and Light bars – SparkFun
• Voice changing module, sound-to-light module and record/playback module – Electronics123.com
• SLA Batterys, wire, switches, project boxes and other miscellaneous items – All Electronics
• Geiger counter sound effect – I searched several places and I don’t remember exactly where I got the one I used, but freesound is a good place to look.

photo goodness: [click on image for full size]

This is a shelf I built using Kee Klamps and 1-3/8″ top rail fence post.

Note: I made some errors in the Kee Klamp prices and the quantity of the Horizontal Swivel Socket Member please note the changes.

I purchased the Kee Klamps from Simplified Building Concepts, you can also get them from Grainger and McMaster-CARR prices are about the same anywhere you go (read: expensive) but Simplified Building seemed to have a better selection. The Kee Klamps are awesome and I could come up with a ton of things to build with them, but there a bit cost prohibitive to build with. All in all though they work quite well. I couldn’t find the weight bearing specifications of the Kee Klamps but I was able to stand on the middle shelf (~160lbs) without failure. This was an expensive project mostly due to the use of the Kee Klamps, but they sure are cool.

Kee Klamps Parts List:

• 4 x Type 20-6 Side out Elbow (1″)
• four 8 x Type MH50-6 Male Single Horizontal Swivel Socket Member (1″) (one for each corner of the top and middle shelf)
• 4 x Type 61-6 Flange (1″)
• ~$240.00 ~$131.34 (includes shipping to my house)

Other Parts:

• Pre-cut 24″x24″ plywood from Home Depot (for shelves)
• 4″x2″ for the bottom shelf bracing
• 1″x1″ for top and middle shelf bracing
• 1-3/8″ top rail fence post from Home Depot
• 2″ Casters (need to be able to pull it out to get the network equipment behind it)
• Miscellaneous nuts, bolts and screws
• Finish of your choosing (I used clear polyurethane)
• ~$120.00

Related – Zero Point Shelf

For a more elegant way to frame a t-shirt (on the cheap) see “Framing a t-shirt (on the cheap) REDUX“

So I have this t-shirt that I love, thing is it’s getting to the point where the silk screening is starting to peel of. It wouldn’t be long before it all peeled off completely if I kept wearing and washing it. I didn’t want to throw it away and I didn’t want it to sit in my closet unseen. Since I’ve also been looking for things to fill the empty walls in my room I decided to frame the shirt, my first thought was to use a jersey display case to show the whole shirt in all its glory; I found out though that jersey cases are quite expensive to expensive for a t-shirt I paid $15 for. I had several ideas; however most of them were in overkill zone. Then while at Target (getting shaving supplies) I came across an acrylic box frame that I thought might work. Turns out the $3.99 acrylic frame worked quite well, I need to learn to take more pictures during the process of something like this but it’s pretty simple.

Materials Needed:

• Acrylic box frame – I got mine at Target for $3.99
• Masking tape
• Razor blade
• Scissors

Process:

• The frame I got (conveniently) came with a cardboard insert, a box that fit inside the frame to hold the picture in place. Since I wasn’t going to put a picture in the frame I cut the top off of the box insert (used masking tape to hold it together) to allow space for excess t-shirt.
• I fitted the t-shirt over the box insert – this part took the longest, getting the shirt centered on the insert. Before I put the shirt in the frame I used a lint roller to remove any, well… lint from the shirt and cleaned the inside of the frame using Windex and an old cotton t-shirt.
• Once the t-shirt was in the frame I stuffed the remaining shirt in the back of the frame and used masking (two layers in separate directions) tape to cover the back to hold it all in. Using a razor blade I cut the excess tape from around the edges.
• Poked a hole through the masking tape for a nail.
• Hung on wall

[click on image for full size]

Related – Framing a t-shirt (on the cheap) REDUX

Related – Industrial Picture Frame

A couple of weeks ago things got pretty hot here in Vancouver Washington, with temperatures hitting the low 100s. I was really tempted to go out and buy an air conditioner, but it only gets really hot for maybe two weeks here and after that the proper use of fans does the job fine. So it was hard to justify spending the money on air conditioning only to end up using it for maybe two weeks out of the year. But when it’s 100+ degrees outside a fan isn’t much help. It was hot and I needed some relief, so I put to use some basic science – heat rises. Fortunately my house is on a raised foundation and even better the access to the underside of the house is in my closet. I pulled the access cover from the floor and immediately realized that my idea was golden – the temperature was easily 15-20 degrees cooler under the house than it was inside the house, which makes sense because –

• Heat rises so it makes sense that it would be cooler under the house than say above it
• There is no significant amount of sunlight that gets under the house so even on really hot days it’s nice and cool under the house

To test my theory I took a box fan and stuck it over the opening, turned it on and was greeted with air that felt like it was refrigerated – at least compared to the 100 degree air in the room. The other bonus was that there were no strange odors coming up from under the house. There were a few things I needed to still work out though –

• I needed something more beefy than a box fan
• I needed to direct the air out of the closet and into the room
• I needed to still be able to walk into my closet without falling into the hole

To solve the fan problem I went and got a Patton industrial fan which I knew would provide sufficient air flow. I then used some cardboard and duct tape to make a duct-work that forced the air to flow up from under the house and into the room. I used some boards to cover the hole and folded the carpet back so that only about 8” of the hole was exposed.

All said and done if I kept the blinds closed during the day and started the fan early enough in the morning the room stayed comfortably cool. Opening the window a crack helped to evacuate hot air if the fan had not been turned on early enough. As well as it worked though there are some caveats –

• You need a house that is on a raised foundation
• You need a hole in the floor of the room you want to cool
• It’s basically a one room system, unless you cut a hole in the floor of all your rooms, or you came up with some kind of whole house duct-work to circulate the air throughout the house
• It’s loud – this is mostly due to the fan I used, even on low Patton fans are loud
• It takes up closet space, at least in my case
• There are houses where you would not want smell the air from under the house, fortunately I didn’t run into this issue
• It’s ugly – I didn’t spend much time on aesthetics

I unfortunately didn’t take any temperature measurements when it was still hot but I can say that if the outside temp was 100+ degrees and I started the fan early enough (to keep hot air from getting trapped the room), and kept the blinds shut I’d guess that the room stayed around 70-75 degrees. Now that the temps have mellowed out as long as I keep the blinds shut I don’t need to start the fan in the morning and only run it if I feel hot.

Basically my only cost was $40.00 for the fan, the cardboard and tape I already had. An air conditioner sufficient for my room would be about $200.00+ $600.00 plus wiring a separate outlet for the unit (1000+ Watts @ 10 Amps – needs its own circuit.)

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