|
 Now with timer function and wider dynamic range
Ultra long-term stability error of approximately 0.1% per five years.
Virtually removes effects of system leakage during measurement. Uncorrected leakage <10 fA over temperature range
Eleven user-defined bias settings from -500 V to +500 V
Read out in C, A, R, Gy, Sv, Bq, and more
The 35040 Advanced Therapy Dosimeter is a reference grade instrument used to measure the charge and current from ion chambers in Radiation Therapy, and provides bias voltage for all commonly used chambers. The ATD large clear display offers direct readings of charge, current, time and radiation units over a wide range. The user can customize the display for basic use or for specialized applications such as brachytherapy. The 35040 Advanced Therapy Dosimeter exceeds the recommendations of calibration laboratories for leakage, linearity, and stability by a wide margin.
The 35040 Advanced Therapy Dosimeter, provides the long-term stability and accuracy demanded for calibrations, quality assurance programs, and protocols in Radiation Therapy.
The 35040 Advanced Therapy Dosimeter is fully stable within five minutes. In battery operation or using AC Line, the ATD measures dose and effective exposure time in a single exposure, thus eliminating the need for multiple exposures for Cobalt 60 and brachytherapy measurements. Front panel controls select ion chamber calibration factors, facilitate entry of temperature and pressure values for air density correction, allow bias voltage selection, threshold level, timer control, and choice of display screens. The user-customized display screens can simultaneously show dose, exposure time, dose rate, effective exposure time, average current/rate, accumulated charge/dose, bias voltage, leakage, and other important information that ensures the validity of the instrument.
The customization software allows design of 16 screens that display conditions, parameters, values and text. Up to 32 chambers factors, 11 bias voltages can be programmed. It is PC compatible and connects via a RS-232 cable.
Features
Wide measurement range, up to 1,000 ΅A and 19.999 mC for HDR Brachytherapy applications
Automatic reset and hold of measured valued between exposures
Front panel adjustment of exposure threshold and user disable of threshold to permit manual operation
Thirty-two ion chamber calibration factors
Automatic power-down after user-specified time period, when operating from battery supply
Annunciators warn of low battery, low bias, and operational errors
Large capacity battery provides eight hours of continuous operation; fast recharge in less than three hours, even during operation
AC line operation over the range 100 to 240 VAC and 47 to 63 Hz without operator intervention
Charge and current calibration factors entered by calibration laboratories at users option
Front and rear panel ion chamber connections
Specifications
Dose and Rate Display
|
Charge
Full Scale
200.00 pC
2.0000 nC
20.000 nC
200.00 nC
2.0000 ΅C
20.000 ΅C
200.00 ΅C
2.0000 mC
20.000 mC
|
Charge
Sensitivity
0.01 pC
0.0001 nC
0.001 nC
0.01 nC
0.0001 ΅C
0.001 ΅C
0.01 ΅C
0.0001 mC
0.001 mC
|
Charge
Sensitivity
0.01 pC
0.0001 nC
0.001 nC
0.01 nC
0.0001 ΅C
0.001 ΅C
0.01 ΅C
0.0001 mC
0.001 mC
|
Current *
Sensitivity
0.1 pA
0.001 nA
0.01 nA
0.1 nA
0.001΅A
|
|
* Average current is displayed with ten times greater resolution
|
|
Effective Exposure Time Ranges
|
|
Full Scale Range
|
Display Resolution
|
|
59.99 s
|
0.01 s
|
|
5 hrs 33 min 19.9 s
|
0.1 s
|
Stability: Designed for ultra long-term stability error of approximately 0.1% per five years.
Leakage: Virtually removes effects of total system leakage during
measurement. Uncorrected leakage <10 fA over temperature range.
Linearity: Maximum non-linearity variation from straight line of 0.1% of all charge and current ranges.
Resolution: 0.005% of range (4.5 digits) for charge, dose, average rate and average current; 0.05% of range (3.5 digits) for current and rate.
Warm-up: Fully meets specifications within five minutes of applying power.
Measurement Accuracy: 18° C to 28° C (64° to 82° F)
Charge ± (0.20% readings plus two counts)
Current ± (0.20% reading plus two counts)
Bias: Eleven (11) user-programmable steps from -500 V to +500
V in 0.1 volt increments. Accuracy ±0.3 volt for loads <0.2 mA. Front panel selectable.
Ion Chamber Calibration Factors: Thirty-two (32) user- programmable calibration factors. Front panel selectable.
Display Unit: All practical radiation and electrical units.
RS-232 Computer Configuration: For customizing and data
transfer.
Physical Dimensions: 9.4 W x 10 D x 4.0 H
Weight: 10 lbs.
Power: Internal Lead Acid Battery; Integral Charger Operates 100 to 240 Vac (47 - 63 Hz)
Connectors: Triax BNC-F front/rear or Triax TNC-F/M front/rear
|
