Re:H-3 efficiency on LSC

[Ninni Jacob <njacob@gsosun1.gso.uri.edu>]

Thanks to all of you who replied to my question.  I am sorry I cannot
reply individually.

Fo those of you who asked, the efficiencies for the two H-3 stds are
different on the same LSC.

The LKB std came with the LKB machine.  The manual says that the efficieny
for H-3 is 62%, and thats what it comes out to be.
This instrument was bought in 1986.

Later we bought new Packard stds and when I counted those on the same
machine, the efficiency for H-3 is only 49%. The new Packard stds are
unquenched.  I do not know about the LKB stds. (For those of you who
asked, I did account for decay).

As some of you suggested, I am beginning to think that it may be due to
the different cocktails that were used.  Does this mean that we have to
know what cokktails are being used in standards? Could this also mean that
we may have to come up with our own in-house standards depending on what
coktail we use?