Hacking Interview Question:

How do I build a Red Box?

Submitted by: Administrator

Red boxes are commonly manufactured from modified Radio Shack tone
dialers, Hallmark greeting cards, or made from scratch from readily
available electronic components.

To make a Red Box from a radio shack tone dialer, open the dialer and
replace the crystal (the largest shiny metal component) with a crystal
close to 6.5Mhz. The most popular choice is the 6.5536Mhz crystal.
When you are finished, program the P1 button with five *'s. That will
simulate a quarter tone. Note that the tone dialer you start with
must have programmable buttons.
Submitted by: Administrator