In the Cymric seismic test, the source is hammer. We used two types of geophones: One three-component Episensor and 12 Geometrics vertical geophones. The first GEOD is connected to the Episensor and the second is connected to the 12 vertical geophones. 

Therefore, channel 1-3 corresponds to the X, Y, Z component of the Episensor. channel 4 -- 12 are empty. Channel 13 -- 24 corresponds to the vertical geophones, the rest of the channels are empty. 

The layout is show in the Cymric_seismic.pptx file.