A communication apparatus is provided. The apparatus includes a printed circuit board having a thickness that complies with an intrinsic safety physical separation specification. A first pair of capacitive plates are disposed on opposite sides of the printed circuit board and are arranged to form a first capacitor having an insulating layer of the printed circuit board forming a dielectric material for the first capacitor. A second pair of capacitive plates are disposed on opposite sides of the printed circuit board and are arranged to form a second capacitor having the insulating layer of the printed circuit board forming a dielectric material for the second capacitor. A modulator is coupled to the first and second capacitors and is configured to receive an input signal having an input signal frequency and to provide a modulated signal having a frequency that is higher than the input signal. A demodulator is coupled to the first and second capacitors and configured to detect the modulated signal and provide a demodulated signal having the input signal frequency.