From Keysight DSO1072B, the command "TIM:SCAL: can't accept zero as the first chacter. Ex: 0.2, 0.0002, ... The time value is in a 1-2-5 sequence (for example, 1.0E-9, 2.0E-9, 5.0E-9, ..., 1.0E+00, 2.0E+00, 5.0E+00) from: https://sigrok.org/gitweb/?p=libsigrok.git;a=blob;f=src/hardware/rigol-ds/protocol.c;h=201e0a31b920d6761c6c7104e01a52e14e3431cd;hb=34ce4d8258e61cb98446e027b2af0d6b522388fc#l292 https://www.keysight.com/upload/cmc_upload/All/1000_series_prog_guide.pdf https://sigrok.org/bugzilla/show_bug.cgi?id=1576 https://sigrok.org/bugzilla/show_bug.cgi?id=1578