|
Detector |
Power Supply
|
| 1. |
Type: Vented Ionization Chamber,
Fully Guarded |
1. |
Rechargeable gel-cell batteries,
4.0 volts (nominal) |
| 2. |
Quantity: 1, located for CAX
measurements |
2. |
Battery charger: AC/DC Adapter
(110 VAC 50/60 Hz supplied with unit) |
| 3. |
Volume: 0.6 cm3
|
|
a. 6-12 VDC (Damage will occur above 16 V)
|
| 4. |
Parallel Plate Separation: 4mm
|
|
b. Center positive
|
| 5. |
Detector Bias: 400 volts
|
|
c. Greater than 300 milliwatt
|
| 6. |
Collection Electrode: 1.4 cm Dia, carbon
|
|
|
| 7. |
Inherent Buildup
|
End Panel |
|
a. Actual; Acrylic, 0.79 cm; Mylar, 0.038 cm
|
1. |
4 digit LED display, 2 cm high
|
|
b. Effective; 1.0 ± 0.1 g/cm2
|
2. |
DC input power jack, 2.5 mm diameter center
pin |
| 8. |
Inherent Backscatter: Acrylic, 2. 3 cm
|
3. |
Power switch, On/Off, labeled (1/0)
|
| 9. |
Radiation Measured |
4. |
Indicators: 3 green indicators |
|
a. Photons, Co-60 to 25 MV
|
|
a. "CHARGING" - Battery charging
|
|
b. Electrons, 5 MeV to 25 MeV
|
|
b. "STATUS" - Battery status:
Full = off, 20-80% = solid on, <20% = rapid blink |
| 10. |
Beam Limits |
|
|
a. Maximum dose per pulse, 0.055 Gy
|
|
c. "ON" - Power on and processor operational
|
|
b. Maximum average dose rate, 0.63 Gy/s
|
5. |
Controls |
|
|
|
a. “CALIBRATION” – Pushbutton
switch saves a measurement as a standard in the selected memory |
|
Construction |
|
|
1. |
Single circuit board for high
reliability, mounted between acrylic plates, providing a high quality
EMI shield. Electronics placed at display end and must be kept out of
direct radiation |
|
b. “*” - Pushbutton switch selects auto mode
for memory selection with radiation measurement |
| |
c. “SELECT” - Pushbutton switch
manually selects memory location for calibration or measurement |
|
|
d. “DISP.” – Potentiometer
adjust of display brightness |
| 2. |
Top covered with durable
alignment template |
|
|
6. |
Test Points |
| 3. |
Dimension: 25. 5 cm wide, 40 cm
long, 4.7 cm thick |
|
a. “G” – Ground
|
|
|
b. “B” – Battery voltage (3.50 –
4.59 volts, operational range) |
| 4. |
Weight: 4.9 kg
|
|
|
|
|
c. “C” – Charger voltage (0.05
–4.59 volts), Charging current = [(C-B)/0.1] |
|
Alignment Template |
|
| 1. |
Light Field Alignment: 10x10, 20x20 cm square
|
|
|
| 2. |
Tolerance Marks: ± 2 mm at the
light field corners |
Instrument Firmware |
|
1. |
Execution: EPROM located in microprocessor |
| 3. |
Detector: Located by blue circle
|
2. |
Update: Requires new microprocessor
|
| 4. |
Cross Hair Intersection : 2 mm
diameter circle within the blue detector area |
|
|
|
Measurement Electronics |
|
|
1. |
Detector Measurement: Unipolar
Current to Frequency |
|
Calibration |
|
|
15 memory locations provide
correction factors which calibrates the display to read 15 different
beams. After calibration the display is in units of % of the stored
standard value |
|
a. MOS-FET operational amplifier
|
|
|
b. Maximum pulse frequency, 20,000 Hz
|
|
|
c. Charge per pulse, 2. 5 pC
|
|
|
d. Feedback capacitor, 220 pF
|
|
|
|
e. Amplifier supply voltage, 5V
|
| Software
Functions |
|
f. Update Frequency, 1 second
|
| 1. |
Automatic Leakage Offset Compensation
|
2. |
Capacitor Reset: Pulse charge feedback
|
| 2. |
Automatic Measurement Reset
|
3. |
Single Gain
|
| 3. |
Automatic Air Density Correction
|
|
|
| 4. |
Displays measurement as percentage of
standard value |
Temperature and Pressure Correction |
| 5. |
Manual or automatic selection of
standard output memory locations |
|
The CHECKMATE employs internal temperature and
pressure sensors. With the information from these sensors the CHECKMATE
performs automatic air density correction of all measurements |
|
|
| 6. |
Battery monitoring and status indication
|
|
| 7. |
Standard outputs for fifteen
beams conditions |
|
|
|
|
|
|
Optional
Accessories (Purchased separately)
|
|
|
1. |
Buildup Plates:
|
|
|
|
a. 2 cm acrylic plate
|
|
|
|
b.1 cm acrylic plate
|
|
|
2. |
Bracket for mounting in shadow
block tray of accelerator |
|
|
|
Demonstration
