Under certain conditions, EMI or RFI levels from the Macintosh IIcx could
be high enough to set off the ringer of a wireless telephone sitting on
its cradle (the condition does not exist when off the cradle).
A Macintosh IIcx with HD40 SC and 2MB RAM with Apple 8-bit video card and
AppleColor monitor running Director performed this trick. Every time an
error condition existed, the telephone was triggered when we closed the
error dialog box.
We did not try other software. MoC certification number of the telephone
is 5382227A (Send Freq = 49.770 MHz, Recd Freq = 46.710 MHz). The
telephone was approximately 4 feet from the monitor, and it is currently
Bell's top-of-the-line model (Promenade 1250).
Complete testing has not been done, but garage door or alarm systems may
also be affected.