Embodiments include apparatuses, systems, and methods associated with modulating a clock signal to encode information. A system may include a plurality of dies including a first die. The first die may include a real time clock (RTC) circuit to receive clock information associated with a shared clock signal that is shared among the plurality of dies, and modulate a RTC signal to encode the clock information. The first die may further include an output terminal coupled to the RTC circuit to pass the modulated RTC signal to one or more other dies of the plurality of dies. A second die of the plurality of dies may include a decoder to receive the modulated RTC signal and extract the clock information. The second die may adjust and/or condition the shared clock signal based on the received clock information. Other embodiments may be described and claimed.