Just tried your example sac file with GEE, our education data viewer,
yet another test passed. GEE is here if you are interested.
Only additional thing I noticed was the kinst, kstnm and knetwk
headers which were MyInstru, MyStatna and MyNetwor. They should
probably either be somewhat meaningful or set to the null value.
KINST is "Generic name of recording instrument. " and so you could
put something in there to identify either the mac's accelerometer or
maybe SeisMac itself?
KNETWK is the network, but since you are not part of a network,
probably should be undef or maybe XX which is seed for "not a
KSTANM might be something you could pull from the Mac's name or allow
users to configure this?