are set within the frequency range of 335 to 500 khz and are assigned in a manner to allow enough tolerance to eliminate the need for tuning each pen 200 the status of writing tip 205 is determined by micro switching mechanism 235 switching mechanism 235 is operable when writing tip 205 contacts paper pad 40 the pressure of writing tip 205 on paper pad 40 is sufficient to activate switch 235 and transmitter 230 non writing tip 210 is retractably mounted in cap 220 and is adapted for use with the touch sensitive display 25 a which is associated with pdd 15 when cap 220 is positioned over writing tip 205 non writing tip 210 is retracted within cap 220 as shown in fig3 b when cap 220 is positioned over second end 207 of pen 200 which is defined diametrically opposite from writing tip 221 second end 207 thereof cooperates with non writing tip 210 to force non writing tip 210 to extend outwardly from aperture 221 defined on cap 220 as shown in fig4 a and 4 b therefore when the user removes cap 220 from writing tip 205 to begin writing on notepad 10 the user can also position cap 220 over second end 207 of pen 200 to extend non writing tip 210 outwardly from aperture 221 defined on.