... geophone. CDJ middle & high frequency geophones, 4,10,15,28,30,40,60,80 or 100Hz, are widely used to seismic ... /P60CDJ-Z/P100 Vertical/HorizontalVertil/HoriVerti/HoriVerti/HoriVerti/HoriNature Frequency Fn (Hz)30±5%38±5%40±5%60±5%100±5 ... )0.28±5%0.26±5%0.26±5%0.30±5%0.25±5%Coil Resistance Rc (Ω)500±5%650 ...