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LUDLUM MODEL 2929 DUAL-CHANNEL SCALER January 2016 Serial Number 248597 and Succeeding Serial Numbers...
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LUDLUM MODEL 2929 DUAL-CHANNEL SCALER January 2016 Serial Number 248597 and Succeeding Serial Numbers Shown with a Model 43-10-1...
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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.
Operating Procedures Calibration Procedures High Voltage Adjustment Procedures Data Output Function Identification Function Source Output Signals Removing Data from the Model 2929 Optional Equipment Model 264 Printer Model 464 RS-232 Interface Model 464-2 Two-Channel Counter Parts List Model 2929 Dual-Channel Scaler...
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Model 2929 Scaler Technical Manual Scaler Board Clock/Logic Board Dual Audio Board 6-Digit Readout Board Mother Board Preamp Board Wiring Diagram Drawings and Diagrams Ludlum Measurements, Inc. January 2016...
The Model 2929 is powered by a 95 to 250 Vac wall transformer with an output of 24 Vdc. It has a built-in detector high voltage power supply with front panel readout, as well as adjustable count time periods ranging from 0.1 to 990 minutes.
Model 2929 Scaler Technical Manual Section 2 Section Specifications Power: 95 to 250 Vac wall transformer with 24 Vdc output, 50-60 Hz single phase (typically less than 100 mA) Beta-gamma lower threshold is adjustable from 4 mV, Input Senstivity: beta-gamma upper threshold is adjustable from 25 mV to 100 mV, and alpha threshold is adjustable from 175 mV.
Model 2929 Scaler Technical Manual Section 3 Section Controls and Functions Front Panel a 10-turn potentiometer control for adjusting HV from 200 High Voltage: V to 2500 V. It provides a linear adjustment of the detector voltage supply. Changing the detector voltage will cause the detector gain to change. A linear change in voltage will cause an exponential change in detector gain.
Model 2929 Scaler Technical Manual Section 3 a rotary control used to vary the audio output of the Beta-Gamma Vol: beta-gamma channel from off to full volume. a rotary control used to vary the audio output of the alpha Alpha Vol: channel from off to full volume.
Pollution Degree 2 (as defined by IEC 664). Cleaning Instructions and Precautions The Model 2929 may be cleaned externally with a damp cloth, using only water as the wetting agent. Do not immerse the instrument in any liquid. Observe the following precautions when cleaning: 1.
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If the wrong power converter is used, the instrument and/or power converter could be damaged. The Model 2929 is marked with the following symbols: DIRECT CURRENT (DC) (IEC 417, No. 5032): designates an input receptacle that accommodates a power cord intended for connection to DC voltages.
“crossed-out wheelie bin.” This notifies the consumer that the product is not to be mixed with unsorted municipal waste when discarding; each material must be separated. On the Model 2929, the symbol will be placed on the rear panel.
Section 6 Section Operating Procedures Once the Model 2929 is calibrated for use with a specific detector, the high- voltage operating point must be determined. See HV adjustment procedures below for details on selecting the proper operating voltage. Selection should be based on the count rates being Count time: observed and the desired statistical accuracy.
Model 2929 Scaler Technical Manual Section 6 Adjust the GAIN control located internally and to the right-hand side of the instrument for a positive pulse amplitude of 200 mV (at the AMP OUT connector). This completes the amplifier gain calibration. The optimum amplifier gain should be approximately 20.
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The following procedures describes the determination of the operating voltage for a Model 43-10-1 detector, which is commonly used with the Model 2929 dual channel scaler. Note that certain criteria must be met for the background counts, source efficiencies, and crosstalk.
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Model 2929 Scaler Technical Manual Section 6 c. Alpha crosstalk in beta channel less than or equal to 10% d. Beta crosstalk in alpha channel is less than or equal to 1% e. Beta background is less than or equal to 80 cpm f.
Bit 1 Bit 2 Bit 3 Bit 4 Function Source All functions are from Model 2929 to accessory except: PIN 2 Printer Ready PIN 6 Count PIN 7 Hold Output Signals Output signals are CMOS with LO = GROUND and HI = VOLTAGE on Pin 8.
Pin 7 Hold: Signal should be pulled low to stop counting. Removing Data from the Model 2929 When the Model 2929 has timed out and counting stops, a HI pulse appears on pin 1 (count complete). This pulse is approximately 2 milliseconds wide and is used to signal the accessory unit that data is ready to be transmitted.
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The suggested circuit for this is shown in Figure 2. Pins 9 and 10 are +5 V pulses and are present even if the Model 2929 is not in a count cycle. Figure 2 Ludlum Measurements, Inc. Page 7-3...
ON. Model 464 RS-232 Interface The LMI Model 464 RS-232 interface connects to the Model 2929, allowing communication between the scaler and a device with an RS- 232c I/O (Input/Output), such as a personal computer (PC).
NOTE: The Model 464-2 accumulates counts independently from the Model 2929 and its internal timer. Pulses are sent to the Model 464-2 counters, regardless of the status of the Model 2929 control board. This allows the user to take timed counts at the Model 2929 without affecting the serial port operation.
Model 2929 Scaler Technical Manual Section 9 Section Parts List Reference Description Part Number Model 2929 Dual- UNIT Completely Assembled Channel Scaler Model 2929 48-1426 Power Supply Board, BOARD Assembled Power Supply Drawing 337 x 27 5337-031 CAPACITORS 100pF, 3kV 04-5532 2.2µF, 20V, DT...
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