All tests must be standardized and run under the same conditions. The graphs used in the original article had a variety of horizontal and vertical scales. By starting at -20 dB, low end, 'into the noise' performance can be investigated. Since most HF digital modes are designed for operation within a 500Hz bandwidth, it would be best to test them at that bandwidth. Unfortunately most modern propagation analyzers have a 4000-5000Hz bandwidth, so results must be judged accordingly.
Many hams still use older equipment which is prone to drift.
Since the test equipment is far more stable than the average HF rig, the problem of drift is sometimes unfortunately overlooked. However, it should be noted that on-line compression with run length encoding acts on data based upon content. Other modes that use precompression techniques will compress all data, rather than parts of it. In either case the file length is insignificant. The original QST data takes this into account, so we offer no changes, only an explanation.