Cellular Phone Talker-Over

Use an old Motorola analog AMPS cellular phone and an external frequency transverter to transmit over someone's cellular phone conversation.

By using a standard Motorola cellular phone (in TESTMODE) as a low-power signal source (825-850 MHz), with the microphone enabled, and an easy to construct frequency transverter, you can talk over someone else's cellular phone.

A Motorola phone in TESTMODE has an option to enable carrier (transmit) on any of the cellular channels between 825 and 850 MHz, with the standard 30 kHz spacing.  By using this as a signal source and mixing it with a simple 45 MHz crystal clock oscillator, you can then transmit on any of the cellular phone's RECEIVE frequencies between 870 and 895 MHz.  The transmit audio option (microphone enable) will then allow you to modulate the new transmit frequency, usually with rude comments.

The unsuspecting target will hear your voice overriding their current cellular phone conversation.  It won't, or shouldn't, cause the target's phone to hang-up).

A high power RF amplifier should be added for maximum effect.  The normal RF power amplifier in an old cellular phone will work in a pinch, as will the antenna.

See this section for more information on programing Motorola phones in TESTMODE.





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