Gamma ray spectrometer (Integral Minim Based)

Gamma ray spectrometer (Integral Minim Based) [ TYPE : GR 612 ]

Technical Data

Gamma Ray Spectrometer type GR612, developed & manufactured by Nucleonix Systems is a low cost integral model specially designed to serve the requirements of P.G.Colleges & Universities both for teaching & Research labs. Considerable cost saving is achieved because of optional design & Integral construction, without any degradation in performance. It is designed around microcontroller which is used basically to derive timer, counter functions & also to set required HV for the detector, along with support pheripherals chips. Also all the required data storage & caculations are done using microcontroller in embedded coding.


+15V, -15V, +24V & 5V are generated in LV PCB, to powerup all the circuits.


(0 to 1500V) @ 1mA HV is adjustable by a ten turn the helipot & dial.

a. HV Output: Positive polaritis

b. Ripple & noise : Low the 25mV

c. Regulation : Better than 0.5%


a. Input Polarity : Positive or Negative

b. Total Gain (Typical) : 600 (Approx.)

c. Ouput (Bipolar): 0V to 8V (usable recom mended Linear range)

d. Max.Output : 12V (Saturation Level)

e. Shaping : 1µsec


a.Input: Unipolar or Bipolar with a +ve leading edge 0 to 10V

b. Output Pulse Polarity: Positive

Pulse Amplitude: +5V

Pulse Width :0.5 micro sec

c. LLD output pulse amplitude: +5V

Output pulse width: 0.5 micro sec

Base line variable by : 10 turn helipot / Dial

Base line variation : 0 to 10V by helical potentiometer

d.Window width continously variable by helical potentiometer / Dial

Window : 0 -1V in WINDOW mode

ULD range: 0.10V in NORMAL mode

e.LLD, ULD & MODE switch, controls have been provided on front panel

a.Display : 20×2 LCD Dotmatrix display has been provided to indicate data counts & Elapsed time
b.Preset time : 0-9999 seconds
c.Command Buttons : START, STOP, PROG, STORE, INC & DEC command buttons have been provided on the front panel key board
d.Modes of Data Acquistion: (i) Counts for a preset time (ii). CPS (iii). CPM
e Preset Time Selection: Programmable through switch control buttons
f.Data storage : Upto 1000 readings
g.Programmability : includes selection of preset time storing / recalling of data, starting and stoping of acquistion, lable assignment for data counts such as BG (back ground), ST (standard) and SP (samle).
h. Serial port : This module additionally has built-in RS232C serial port for down loading the data into PC.

a. To findout the resolution of scintillation detector for Cs-137 & FWMF.

b. To findout best operating voltage of the detector.

c. To findout linearity of GRS with different Gamma Isotopes.

d. To findout the energies of an unknown Isotopes.

e. To plot Co-60 spectrum and findout the peaks interms of baseline channels and calculate per channel energy.


The system finds wide range of applications in nuclear research and academic fields which include analysis of Gamma Radiations Identification of unknown isotopes and their relative adundance Measures the strength of Radioactivity of sample Useful in radiotracer techniques Can be used for protein bound iodine studies in medicine using well type scintillation detector etc. Swipe sample counting in Health Physics Labs.


Scintillation detector with flat type NaI crystal of 1″X1″ or 1 ½” X 1 ½” or 2″ X 2″ or 3″ X 3″ flat or well type detector of 1 ½” X 1 ½” or 2″ X 2″ of NUCLEONIX make or its equivalent is compatible to GR611(I). The output of these units (taken from preamplifier) is POSITIVE for all Nucleonix make Scintillation detectors. Hence the input polarity of the amplifier in GR611(I) is to be selected for POSITIVE. Scintillation detector preamplifier required LV supply of -12V is drawn from the GRS(I) rear panel. So, also the HV bias supply for the PMT of the detector assembly is also drawn from GRS(I) rear panel. Preamplifier of the scintillation detector is a charge integrating type of preamplifier.

Serial Port (RS232C) (Optional):

Built-in serial port facilitates stored data transfer under PC programme control. This transferred data can be further processed if required by the user in PC.