Embodiments of the invention include expandable, implantable devices and methods with a locking feature. The circuit includes a pulse width modulator circuit configured to generate a pulse width modulated signal having a pulse width that varies responsive to an average voltage across the relay coil, including a capacitor of an averaging circuit coupled in parallel with the relay coil. A geo-position may be transmitted as part of an IP address. Calls are managed using specified functions available through an application programming interface offered by the architecture of the target system. Preferably, the elongate member has a first end of fixedly connected to the left atrial anchor and a portion, proximal to the first end, releasably connected to the right atrial anchor. At the releasing position, the driving member is driven to lift up the bread supporting rack along the toaster slot, and at the toasting position, the driving member is driven to lower the bread supporting rack for toasting the bread slice.