Answer:  The HandECount application software includes a calibration routine that facilitates selecting a proper high voltage in one menu driven step, and to determine the efficiencies for alpha and beta in a second step.  The program prompts the technician to insert the appropriate radiation source for each step.  A choice of radiation sources from the built-in Source Library (previously identified to the program and stored in the program's database) are presented to the technician for  selection before initiating the HV plateau or the efficiency calculation.  All efficiencies are automatically calculated based upon the counts collected and the information input previously into the Source Library for the given source.

Question 2.  Why does the HandECount have three source categories (Calibration, Check Source and Both) in the Source Library?

Answer:  Different users and facilities will have different radiation sources or none at all to perform calibration and check source functions.  Frugal and careful users might well use the same alpha and beta calibration sources for both calibration and check source functions.  Larger institutions often times will keep their higher quality calibration sources at the centralized calibration facility and use less expensive check sources for routine source checking.  In such cases each source may be identified separately.  The idea of identifying a check source as a check source only is that the true efficiency of one check source to the next will inevitably vary and vary yet again from the higher quality calibration sources.  In such cases, the HandECount first sets a system level or instrument level efficiency as determined by the calibration sources.  The individual check sources then have their separate efficiencies determined using the system settings.  In this manner, the check sources can be checked for consistancy from one check to the next without introducing the variance between the calibration and check sources. 

All sources are decay corrected automatically so no adjustments ever need to be made once the efficiency for any source in the library are set.

Question 3.  Why does the HandECount include CPM as one of the units in the source library when specifying the emmission rate since CPM values are typically just the raw counts received from the detector?

Answer:  This is a good question that has puzzled a few users.  Thermo Scientific utilizes many calibration sources which were calibrated in an internal proportional chamber which produces a 100% efficiency.  Our certifications provide us with a CPM value, so for our convenience we have included the CPM option in case your sources also have this type of certification.

Question 4.  Does the HandECount use 2 pi or 4 pi efficiency?

Answer:   The HandECount only ever stores the 2 pi efficiency.  It will automatically calculate the 4 pi efficiency for all units of activity.  If when identifying the source to the source library, the certification is already in a 4 pi activity, the HandECount program recognizes this and divides by 2 to determine the 2 pi efficiency.  Thus the technican may go backwards and forwards between the source library and the sample type units of measurement, and the program will always adjust the conversion constants accordingly.  It could not be any easier!  Those who are too acustomed to having to calculate everything beforehand tend to get tripped up as they are not accustomed to the program handling all these conversions automatically.