A geospatial telephony system initiates conference calls between participants based on location of participants. Then, a first organic light emitting material is provided to the substrate to form the first organic light emitting material in the first pixel area and the second mask is removed from the substrate to expose the first and second pixel areas. The method further involves adjusting the transmission of the second signal A2 on the second line, such that a contribution from the second signal A2 interferes constructively with a signal A1\u2032 at the second end of the first line, where the signal A1\u2032 represents the signal A1 having propagated through the first line.