 |
Home | Applications | Contact Us | |
| Products | Service | Training | ||
|
Home | Applications | Contact Us | |
| Products | Service | Training | ||
|
Download
PDF
|
BETA-X
Cooled Spectrometer Specifications PREAMPLIFIER PERFORMANCE TEST INPUT One 18-in. RG174 coaxial cable with female BNC connector. HIGH-VOLTAGE BIAS INPUT One 18-in. RG59 coaxial cable with female SHV connector.OUTPUTS Two 18-in. RG174 coaxial cables with female BNC connectors. CABLE DRIVE CAPABILITY AND TERMINATION Test Input terminated in 93 W; outputs are series terminated in 93 W and may drive terminated and unterminated 93 W coaxial cables (RG62 recommended). Termination recommended for cable lengths greater than 50 ft.CONVERSION GAIN Nominally 1.3 mV/keV negative output pulse signal for Model 239 Preamplifier; 0.2 mV/keV negative output pulse signal for Model 237 Preamplifier (Si). RISE TIME Pulse rise time typically 25 ns; actual rise time to nuclear event depends on detector characteristics.MAXIMUM OUTPUT Maximum pulse output to a single event is –10 V. MAXIMUM ENERGY RATE 4000 MeV/s.NONLINEARITIES Integral and differential, <±0.05% over 90% of the dynamic range of the preamplifier. BIAS VOLTAGE High-voltage filter capable of supplying needs of detector up to 5000 V bias.TEMPERATURE INSTABILITY £±50 ppm/°C over 0°C to +50°C recommended operating temperature range. POWER REQUIREMENTS Typically +24 V, 50 mA; –24 V, 25 mA.MECHANICAL VALVE OUTPUT CONNECTION 1/2-in. OD tube. GASKETS Provided for connection to user's system.ELECTRICAL CABLE PACK Each BETA-X is provided with a standard cable pack containing: signal cable and test pulse cable (both RG62A/U, 93 W BNC), high-voltage cable (RG59A/U, 75 W SHV female), and a preamplifier power cable (9-pin D connector, male). Supplemental or extra cable and connector options are available on request. AUTOMATIC, HIGH-VOLTAGE SHUTOFF The cryostat on all three models of the BETA-X Spectrometer contains a temperature sensing element attached to the cooling path. The sensing element connects to a hybrid monitoring circuit, which is incorporated into the preamplifier electronics. An output cable from the preamplifier is connected to the remote shutdown input on the rear panel of the ORTEC Model 659 Detector Bias Supply. This supply is designed to reduce the detector bias voltage to zero if the remote shutdown input's center contact is provided with a low-impedance (<30 W) path to ground. The monitoring circuit in the preamplifier provides this condition if the detector temperature becomes too high. Although no alarm is provided, the bias supply meter will indicate zero voltage, and system noise will greatly increase after shutoff occurs. For the unit to be operational, preamplifier power must be provided through the power cable.The automatic shutoff should be placed in operation before attempting to apply bias to the detector. Thus the circuit will also prevent the accidental application of bias to a detector which has not yet reached operating temperature. ORDERING INFORMATION
|
|
