The modification of a penless thermal chart recorder to directly display digital telemetry data
James A. Beattie · Defense Technical Information Center (DTIC) · 1982
Presentation of telemetered data from unmanned aircraft trials is currently made on a multipen strip chart recorder. The data from the digital telemetry signal is decommutated, converted to an analogue signal and held at the given voltage between readings. There are a number of drawbacks to the system. Firstly the digital data has to be converted to analogue; secondly the recorder has to be loaded and unloaded with pens; thirdly the pens are offset along the time axis to allow room for the drive mechanism to each pen; finally the data is presented as a smooth analogue curve, when strictly this does not reflect the true character of the information contained in a time multiplexed serial digital data stream.