A system for providing a patient with remote medical assistance at home. A first CMOS switch is deactivated while activating a second CMOS switch to cause the portion of the write signal to transition from a first direct current voltage to a first peak voltage. The one or more biometric sensing devices include a right fingerprint sensor coupled to the processor and a left fingerprint sensor coupled to the processor. The strain relief element includes an end wall having an opening therein, and the strain relief element includes a flexible beam extending axially inward from the opening. Accordingly, linewidth measurement with low cost and high throughput becomes possible. Accordingly, the device for preparing bio-oil can be manufactured into a very simple structure.