This controller is built around the Spark Fun 434 Mhz transmitter module WRL-10534 and six large buttons of different colors. These buttons are distinguishable and attractive. Since they have double-throw switches, the circuit does not need isolating diodes.
By using codes provided by pressing simultaneously two adjacent buttons all of the receivers I have made can be controlled. This determined the pentagon shape since this gives ten such codes, in additional to the six single-press codes.
For full details see:Pentagon.JPG
http://www.projects.worsleyassociate...s/Devices.html