RETURN OF GOODS TO MANUFACTURER If equipment needs to be returned to Ludlum Measurements, Inc. for repair or calibration, please send to the address below. All shipments should include documentation containing return shipping address, customer name, telephone number, description of service requested, and all other necessary information.
Model 2221 Portable Scaler Ratemeter March 2016 1. GENERAL The Ludlum Model 2221 Portable Scaler A single channel analyzer is also featured in Ratemeter is a self-contained counting this unit for use in gamma spectrum analysis. instrument designed for operation with The analyzer may be switched on or off, scintillation, proportional, or GM detectors.
Model 2221 Portable Scaler Ratemeter March 2016 SIZE: 22.9 x 10.9 x 25.4 cm (9 x 4.3 x FINISH: polyurethane enamel with 10 in.) (H x W x L), including handle silk-screened nomenclature WEIGHT: 2.5 kg (5.5 lb), including batteries 3.
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Model 2221 Portable Scaler Ratemeter March 2016 OUT position: The SCA is set up as a CALIBRATION CONTROLS: gross counter. All detector pulses above WIN: 20-turn potentiometer used to the threshold are counted. adjust window width when the window toggle switch, WIN, is in the "IN"...
Model 2221 Portable Scaler Ratemeter March 2016 4. OPERATING PROCEDURES marked difference apparent 4.1 Initial Preparation contribution of these three sources of count. ● Unscrew battery door latch. In the singular case of the GM detector, a ● Install 4 "D" size batteries in the battery minimum operating voltage is required to holder.
Model 2221 Portable Scaler Ratemeter March 2016 5. DETERMINING INSTRUMENT PLATEAU AND SELECTING OPERATING POINT ● Set WIN ON/OFF to OFF. ● Expose the detector to a source and again make a plot of voltage versus count. ● Set MINUTES switch to 0.1 minutes.
● Expose detector to radiation field and while observing ratemeter, increase field intensity ● Full-scale instrument analog meter reading until a decrease in count rate is noticed. For = 200 mR/hr (2 mSv/h). Set the Model 2221 alpha scintillators, detector...
Model 2221 Portable Scaler Ratemeter March 2016 ● Switch Ratemeter Multiplier switch to the ● Confirm HV will adjust from 400 to X100 position and the Response switch to 2400-2500 volts. Ensure HV displayed “F.” reading tracks within 2% of HV output.
Then set HV for approximately 1000 Vdc. ● Connect low-voltage power supply, capable ● Connect voltmeter to pin 1 of U3 of supplying 4.0-5.0 Vdc to the Model 2221 (TLC27M7IP). and plug in amplifier/power supply board (component side to back of instrument).
Model 2221 Portable Scaler Ratemeter March 2016 ● With the HV still set at 1000 Vdc, pin 7 of ● Switch the Window IN/OUT switch to the U3 should be approximately 1 0.1 Vdc IN position and verify that the pulses are present at pin 7 of U105 from 10 to 20 mV while pressing the HV test pushbutton.
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Model 2221 Portable Scaler Ratemeter March 2016 ● With supply voltage set at +5 0.15 Vdc, ● Connect oscilloscope to pin 9 of U10 turn instrument ON and observe display = (ICM7556) and decade sweep generator 8.8:8.8:8.8 for approximately 2 seconds, down to the 1k range.
Model 2221 Portable Scaler Ratemeter March 2016 9.3 Functional/Chassis Checkout Confirm display reads 8.8:8.8:8.8 for approximately 2 seconds, then 261010 This procedure requires a checked-out indicating the program version. amplifier/power supply board and processor board. ● Connect positive voltmeter lead to pin 7 of U3 (TLC27M7IP) on the amplifier/power ...
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Model 2221 Portable Scaler Ratemeter March 2016 ● With the THR control adjusted for 100, Disconnect over-range simulator and confirm overrange function is defeated. adjust R174 Gain (labeled G) for 1.5 Then adjust to fully clockwise position. millivolt input sensitivity.
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Model 2221 Portable Scaler Ratemeter March 2016 ● Turn Lamp switch to the ON position and each digital number count sequence from least significant digit to most significant confirm two lamps in the display and two digit (MSD). Decade pulser count rate to lamps below the meter are illuminated.
Model 2221 Portable Scaler Ratemeter March 2016 10. PARTS LIST Ref. No. Description Part No. C154 0.0015F, 3kV, C 04-5518 C164 0.1F, 100V, C 04-5521 Model 2221 Portable Scaler Ratemeter C165 0.1F, 100V, C 04-5521 UNIT Completely Assembled Model 2221...
The Model 2221 RS-232 port addition allows available. the Model 2221 data to be read as output to a computer or serial printer, by dumping either The Model 2221 will dump the data, no matter the ratemeter or scaler reading as desired.
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