Commercially available neon indicator lamps (also known as Glow Discharge Detectors) are low-cost, sensitive detectors operating at room temperature for mm-wave/Terahertz detection. Furthermore, their high speed operation make them attractive from the stand-point of applications in the far-infrared region of the spectrum, however questions still remain regarding the mechanisms involved in the detection of this type of radiation. In order to study the plasmas generated in these lamps, a DC gas discharge chamber is designed and built. Glow discharge generated using an inert gasis investigated in terms of its far infrared transmission. Keeping the anode-cathode separation constant the transmitted signals are found to be independent of the pressure and applied bias for a pure Neon plasma.