Today we went out and bought two pieces of thin steel for the Crash Cart. They are for mounting the two LCD monitors.

Here’s what the monitors look like mounted. This photo gives you a better idea of how this cart is going to work:

Crash Cart : With Monitors : Full View

Here is a close-up view of the monitors and keyboard tray, from the front:

Crash Cart : With Monitors : Closeup

It was kind of a pain to get all the alignments correct, and they are slightly off level (though they look less level in the photo than in real life). I’d recommend using holes and slots for mounting. The slots will give you a little “play”, which is important if you are doing the drilling on a press or freehand (versus a milling machine).

Here is a rear view of the unit. I used the standard mounting holes (about 4″ on center) to mount the panels. The steel is 3 feet long, 3/4 inch wide and 1/8″ thick. I needed something pretty thin (1/8th) because the included monitor screws aren’t very long (and I didn’t have any fine-thread screws on hand).

Crash Cart : With Monitors : Rear View

I made sure to have the steel sticking out the sides a little bit. This is because I wanted the steel to hit a wall and not a monitor. To protect us from scratches, I carved out a slot in the ends of some synthetic corks and attached them to the ends of the steel. They make perfect bumpers.

Here are a couple of photos of us preparing the kits for the SkillShare Austin event.  This is the complete kit, along with the tools we provided:

DTV Coat Hanger Antenna Kit

A large storage box holds the 20 pieces of pre-cut and pre-drilled lumber, along with a box of spare parts. The black bag hold the tools:

DTV Coat Hanger Antenna Kit Supplies

Evelyn did a test run on Saturday morning to make sure that we got the steps in the right order. We make checklists based on what we learned.

DTV Coat Hanger Antenna Kit Test Run

Each student received a full-sized template, a cutting guide, a slip with some helfup web links, and an assembly checklist.

DTV Coat Hanger Antenna Kit Documents

Evelyn and I had a great turnout for our session at SkillShare Austin. We had 9 people make their own DTV Coat Hanger Antenna — and some of them don’t even have a TV! We’ve already got a new project in the works for the next event at Space 12 in August, where we will likely do the DTV antenna along with the New Project. Stay tuned!

We’ll be posting some photos of the event later today.

Thanks again to the SkillShare Austin people for organizing the event, the folks at Space 12 who are trying to help their community, and to all those people who took part in the workshop. We learned a lot, and hope that you did, too!

Last night I decided to FINALLY start working on the rCube clock kit I had purchased a while back. Here’s a shot of the workbench early in the project:

Electronics Workspace

Let’s go left to right:

• On the far left, out of frame, above, is a spool of solder. I’m right handed, so it’s easier for me to have the solder handy toward my upper left.
• Next you have a I Can’t Believe It’s Not Butter container. WHAT? Yes, I enjoy taking a spoonful of faux butter between soldering connections. Actually it’s what we call our “spit bucket”. We toss scraps (like trimmed leads) and other small garbage into there. Keeps things neater.
• In front of the “butter” we have the portable multimeter. It’s an Agilent U1242A, which you can pick up for about $220. They make a similar model with a frequency generator in the $400 range. For those on a budget a $220 meter might sound crazy, but it’s not at all. This is a meter that will last for years and years. Heck, my old Radio Shack meter is 20+ years old and still working fine.
• Next is the PCB in a Panavise. If you work with electronics you must own a Panavise. This is actually one of FOUR that we own. That’s how good they are. Save yourself a lot of pain and get yourself a good vise. The Panavise in the photo is a Model 350 Multi-Purpose Work Center and can open a full 9 inches! We also have a Panavise Jr 201, a great starter vise (though limited in PCB size) and a Model 381 Vacuum Base. Not enough? How about the Model 333 Rapid Assembly Circuit Board Holder we own–hold up to a 12″ PCB and quick-rotates for component insertion & soldering. The nice thing is nearly all of the heads and bases are interchangable, so you can mix and match.
• Next, behind the parts, if my Cognos mug. Full of coffee.
• Next is our Edsyn 951SX Soldering Iron. You can pick one of these up for the $120 range. Again, like the meter, it’s all about long term. We’ve had this one for about 10 years now and its soldered thousands of joints. Heck, that’s even the original sponge! A good iron makes the difference between an annoying soldering experience and an enjoyable one.
• Behind the soldering iron is our home made solder-fume vent, made out of a mini-milk crate. I’ve written about it before.

Let’s take a moment to look at the Panavise for a moment, and you’ll see why I love these things:

Panavise Closeup

As you can see, this model (because it opens wide) has a nice large base. Not only that, but it has handy areas for holding parts while you are soldering. Very nice. In the photo is an Xcelite MS54 semi-flush cutter. It’s a good deal at around $15.

Oh, how I love good tools. Here’s a close-up of the multimeter:

Agilent U1242A Multimeter

You never realize how shitty cheap meters are until you start using a good one. True RMS and 10,000 count display. Here you can see I’m measuring resistance (363.1 K ohms). The current temperature was 25.7C, in case you need to calibrate. What I love the most about this Agilent is the SPEED. It’s something you don’t realize when using cheaper meters, but they are so darn slow. This thing locks on in an instant and is rock solid. Good tools are worth the money.

Here I am slaving away at the kit. I am wearing, as always, a blue shirt.

Ron Soldering

This is the shirt I was wearing when the Indian Food Attack occurred. I lived to tell the tale, and the blood came out of the (thankfully) synthetic shirt.

Here’s a photo of one of the projects we’re working on. It’s about 3/4 complete:

Crash Cart : Standing Up

It’s a “crash cart” for the garage. In a medical environment it’s a cart that has all the stuff you need if someone is dying. In IT it has a similar meaning: It’s a monitor/keyboard and sometimes PC that you can roll around a data center to hook up to a “dying” server.

In our case, it will be a rolling stand for a garage-based PC. We need a PC in the garage for debugging some stuff (running logic analyzers, programming microcontrollers, etc).

The bottom has a shelf-area for the PC (it’s hard to see now that it’s painted black):

Crash Cart : Base

The shelf at the mid-point you see will be for the keyboard and the mouse. Above that, not yet installed, will be two side-by-side LCD monitors.

The unit is about 5 1/2 feet tall and made out of good-old 2×4′s screwed together. The upright is two of them, and the base are four in a star-like pattern, with an additional 1×4 screwed to the bottom for the casters to ride on. It won’t hold a ton of weight, but it will handle a couple of big PCs without a problem.

A side note on castors: Get big ones. They make things a LOT easier to roll around. We got these 4″ models from Harbor Freight for about $3 each (four needed).

I’ll post some more photos as we install the monitors and the PC.

Below is the corrected temple.

Digital TV Coathanger Antenna Template

Print on 8.5 x 11 paper, tape together, and then tape/glue to your piece of wood (optional). It will make laying out the screws and the wires a lot easier. It is designed for making the 20 inch long model found on the Make site. 

Be sure to print the PDF at 100%. Some software will try and reduce it. It should have only 0.25 inch margins top/bottom. If you print it out and tape it together it should be 20 inches long. If it’s 19-ish then your PDF reader has scaled it. Be careful, it got me, too.

The general measurements are:

First set of screws are 1 inch from each end.
Second set of screws are 7 inches from each end.
Center screws are 10 inches from either end. 

The elements should be symmetrical. In my original template I mirrored the bottom part upside down. I’m so sorry about that.

While putting together the kits I realized that I messed up the template. Page two has the wrong spacing between the elements. I’m really really pissed off that I didn’t spot this, especially since I reviewed it about a dozen times. Now I’ve got tons of wasted wood. Very frustrating.

Anyhow, I’ll post a new template once I’ve fixed it and not so pissed off.

On May 30th and 31st Evelyn and I will be at the SkillShare Austin Weekend Of Workshops event. We will be teaching a workshop on how to make your own coathanger DTV antenna. No tools or experience is required. Just bring yourself and sign up for the workshop. You’ll walk away with a FREE working antenna.

The event will be from noon to six PM at Space 12. The address is 3121 E 12th Ave, Austin TX 78702. It’s about a mile east of the last place (Treasure City) and just west of Airport Blvd. (I think the place used to be a nightclub or something. I’ve never been there.)

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