Remote monitoring of glow tube light output including a logic unit maintaining an indication of a monitored glow tube discharge while no discharge is detected

A glow tube detection system for remote monitoring of light output from at least one glow tube, the glow tube detection system comprising:

• a light channeling device to channel an output of at least one monitored glow tube onto an array of at least one photo detector;
• a frequency filter that eliminates low frequency components from an output of the array of at least one photo detector;
• a threshold detector that detects that an output from the frequency filter indicates that at least one monitored glow tube is discharging light indicating a presence of voltage sufficient to create glow tube discharges;
• a logic unit that creates a logic output that indicates that the threshold detector has detected that at least one monitored glow tube is discharging light indicating the presence of voltage sufficient to create glow tube discharges;
• wherein the logic output
• continues to indicate that at least one monitored glow tube is discharging light indicating the presence of voltage sufficient to create glow tube discharges;
• after the threshold detector is no longer detecting that the output from the frequency filter indicates that at least one monitored glow tube is discharging light indicating the presence of voltage sufficient to create glow tube discharges;
• for a period sufficient to compensate for a glow tube that is flickering rather than operating properly;
• and
• a means for communicating the logic output from the logic unit to a device external to the glow tube detection system.