background image
This is the A-head
159
Chapter 8, How to Hack a Building-Size Display
Figure 8-9: Halogen lamp
You will need to purchase the relays as well. Purchase at least 144 relays
whose contacts are rated for 120VAC at 3 amps; the driving coil should be
rated at 12V DC. Hold on to these relays, as you'll be using them in Step
6.
4. Obtain lamps and build stands
You now need to obtain the lamps that will light up each pixel. Any
medium power lamp can be used, but the CCC found that low-cost halo-
gen work lamps were particularly effective. You can see what one of these
looks like in
Figure 8-9
. Small halogen lamps can be found in most home
supply stores and on the Web (check
http://www.cornerhardware.com/ for
the Regent Quartz Halogen Clip Light model #CL150). The Regent lamp
is nice in that it has a clamp to allow easy and flexible mounting.
You can also use the popular torchiere lamps sold in many home supply
stores. These lamps already have a stand and the light location can be
adjusted. If you choose to use these, you can skip the rest of this step and
proceed to Step 5.
A 150-watt lamp should be sufficient. If you want to use a more powerful
lamp, you will need to select a relay that can handle a larger amount of
power.
The lamps will need to be mounted in the middle of each window so that
the maximum amount of light can be seen on the outside of the building.
Simple plans for a lamp stand are shown in
Figure 8-10
. The CCC built a
simple tripod stand out of 2" x 2" wood planks, using wood screws or nails
to secure the wood together. You may need to experiment with this design
to accommodate your exact placement requirements. Build one first, get it
right, and then build the remaining 143.
24"
12"
Front
50" - 60"
12"
12"
Side
Figure 8-10: Simple lamp stand