So far, oscillators have been designed to perform a specific task while the key parameters such as phase-noise and power consumption are set by the hardware design and not by the communication system in an adaptive way. As the communication channel is often subject to changes, the conditions under which the oscillator operates should be changed as well. Therefore, the concept of design for adaptivity must be considered as a cornerstone in the design of today's telecommunication systems. Accordingly, the concept of phase-noise tuning, introduced in this paper, shows how oscillators can trade performance for power consumption in an adaptive way. The presented model of a quasi-tapped bipolar VCO reveals the resulting trade-offs between phase-noise and power consumption imposed by the design for adaptivity.