The Antique

Back to the LED's.

It turns out that coloring the outside of a mini LED can actually change its hue, but unfortunately, this is only true for "cool" shades. I can change it to blue, purple, or green but not to reddish or orange light. So the next question I'm dying to answer is, how do you change a 5 V dc voltage to alternating voltage? The aim is to make the lights gradually go from dim to strong and back to dim in a cycle. At my disposal, I have the very basic ingredients of electric circuits class - resistors, capacitors, inductors, diodes, BJT transistors, and a MOSFET.

One way that I know is by using diodes. Any other creative answers are welcome.

A random question: what fun things can you do with a motor (indoors) that's a 1990 build, used originally to drive floppy disks (remember those?).

I am thinking of doing something with rotating lights all around my room. I haven't tried it out yet. I will definitely have to make use of gears and other simple mechanical rotation to linear motion devices.

The Wi-Fi Question

I wonder if the cost of setting up universal Wi-Fi or worldwide (or nationwide) broadband outweigh the subscriptions of millions of mobile phone subscribers who have to pay an outrageous amount of money every month for service they don't even use? In USA for example the least expensive voice plan is $39.99 (not inclusive of tax) by Verizon Wireless and Sprint. According to NY Times, an average family spends about $1000 every year on cell phone service. But a decent ISP such as comcast will charge $400 every year, again, for each household. You already can make phone calls from one computer to another using a variety of softwares such as Skype, and text messaging is simply IM'ing. What is higher, the cost of making every highway, every street and every house like the insides of Starbucks, or the $1000 each of a hundred million has to pay every year for cell phone usage, roughly $10 billion?