The probe LB 1238 with proportional end-window counter tube allows the simultaneous, separate measurement of the alpha and beta activity of samples with a diameter of up to 25 mm in the lead chamber
LB 7431. Furthermore, the activity of filters, wipe tests or other sample formats can be verified by direct measurement. When connecting the probe LB 1238 to the basic unit LB 1230, the UMo can either operate in the rate meter or timer/counter mode. Either cps or Bq are displayed; the calibration factors for alpha and beta activity can be determined and entered by the user depending on the existing sample geometry.