Counting Rate Meter Based on a Design by M.I.T.,
Abstract
The Counting Rate Meter herein described was built largely from designs contained in the Massachusetts Institute of Technology report entitled Improvements in the Counting Rate Meter. The purpose in building this instrument was to produce a counting rate meter to operate in conjunction with a recording galvanometer (in this case a 5 milliampere Esterline-Angus recorder) to indicate and record counting rates of from 50 to 20,000 counts per minute accurate to within 5% for randomly distributed pulses. The range of from 50 to 20,000 counts per minute was accomplished in seven separate ranges. This counting rate meter will be useful in studying radiations from sources having half-lives greater than 1 1/4 minutes for ranges 1, 2, and 3 and greater than 50 seconds for ranges 4, 5, and 6 and greater than 25 seconds for range 7. To facilitate easy calibration check of the instrument a Pulse Generator producing pulses at exact multiple and sub-multiple frequencies of 60 cycles per second was included with the Counting Rate Meter. Although the instrument is designed to count beta and gamma radiations operating from a Geiger-Mueller tube, it could be used with a standard chamber and pre-amplifier to count alpha particles. Calibration curves of the Counts per Minute meter are included in the Appendix at the end of this report. The curves are plotted to show the calibration for both random and periodic pulses. The calibration with random pulses was accomplished by measuring the counting rate of a beta-gamma source using a G-M tube and the Counting Rate Meter and checking the Counts per Minute meter reading against a scaler operating from the Scaler pin jack on the Counting Rate Meter front panel. The calibration with periodic pulses was done using the Pulse Generator.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1946
- Accession Number
- ADA322870
Entities
People
- R. L. Sternberg
Organizations
- Oak Ridge National Laboratory