Here's a three-channel beta analyzer that works the way you want it to for liquid scintillation counting.
Only the Mark I Liquid Scintillation Computer has it.
Now there's a beta analyzer for liquid scintillation counting that'll handle almost any sample type or energy. Without troublesome, time-consuming set-up or calibration. It's the exclusive beta analyzer in our Mark I T " Liquid Scintillation Computer. The Mark I's analyzer has three identical, independent pulseheight analysis channels. Each channel has independent lowerand upper-level discriminators and. separate amplifier attenuators —no high-voltage adjustments necessary. Each attenuator and discriminator comes with positive-step, coarse and fine controls that cover any beta spectrum—and also ensure the highest reproducibility. What can you do with the analyzer in the Mark I? For one thing, you can use the upper or lower discriminator in any channel as a base level for integral counting. Then you can directly superimpose this discriminator over one in another channel. This technique is very useful for quench determination by the channels ratio method. Or you can set up the Mark I for counting single-labelled or dual-labelled samples or intermixed samples of up to three different isotope energies. Choose either channels ratio or external standardization for efficiency evaluations. Of course* three individual researchers can use the three separate channels for single-labelled sample-counting with external standardization for quench determination. They'll also be able to take advantage of selected-sample-group programming, individual background subtracters on each channel, and preset count selection and low-count reject on each of the three scalers. We've put a lot of other exclusive features in the Mark I—for example, true electronic data computation and G-O™ (GeometryOptimized) external standardization. Get everything you need to know about the Mark I—consult your Nuclear-Chicago sales engineer or write to us. ««,•-•..·,
n Model nViO fRa 1 " external standard) Model 6S6 3 (Ra- 2S external standard)
NUCLEAR-CHICAGO CORPORATION
351 East Howard Avenue, Des Plaines, Illinois 60018, U.S.A. / Donker Curtiusstraat 7, Amsterdam W, The Netherlands. Circle No. S on Readers' Service Card Circle No. 187 on Readers'Service Card
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