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.