Ludlum Model 500 Pulse Generator

The Ludlum Model 500 Pulse Generator provides the functions necessary for use in calibrating Ludlum radiation detection instruments as well as many other scaler/ratemeter instruments from other manufacturers. The adjustable output pulse rate is displayed on a three-digit LED readout. Potentiometers (both coarse and fine controls) and a multiplier switch provide rates from 1 to 9.9 x 10⁶ counts per minute (cpm). Pulse amplitude is controlled by a multiplier switch and a LO/HI potentiometer, while pulse polarity is chosen by a selector switch. Amplitude may be varied between 0 and a negative or positive 5 V, displayed on an analog meter. The high voltage of the instrument under test is displayed on an analog meter with markings of 0 to 2.5 kV.

Indicated Use Pulse calibration of radiation detection scalers/meters
High Voltage

• Display: Analog readout
• Meter Dial: 6.4 cm (2.5 in.) arc, 1 mAv
• Scale: 0 to 2.5 kV
• Linearity: Reading within 5% of true value

Pulse Rate

• Display: Digital readout, three digit LED display reads from 10 to 990 counts
• Total Range: 1 to 9,900,000 cpm
• Accuracy: Within 2% of true value
• Controls: Fine and coarse adjustment knobs
• Multiplier Switch: x0.1, x1, x10, x100, x1k, x10k

Pulse Amplitude

• Display: Analog readout
• Meter Dial: 6.4 cm (2.5 in.) arc, 1 mA movement
• Scale: 0 to 5
• Total Range: 0 mV to 5 Vdc (positive and negative polarity selectable)
• Accuracy: Within 10% of true value
• Controls: LO/HI potentiometer
• Range Switch: 0 to 5 mV, 0 to 50 mV, 0 to 500 mV, 0 to 5 V

Pulse Polarity

• Switch: Positive/Negative selector switch
• Negative Pulse: Pulse width typically 7.0 µs
• Leading Edge: 0.3 µs
• Pulse Width: 1.7 µs
• Trailing Edge: 5.0 µs
• Positive Pulse: Pulse width less than 2.25 µs

Pulse Output Standard “C” type connector, a “C” type cable is supplied with the instrument
Power 95 to 135 Vac (178 to 240 Vdc available), 50-60 Hz front panel on/off switch with accompanying red LED indicator
Size (H x W x L) 21.6 x 29.2 x 24.1 cm (8.5 x 11.5 x 9.5 in.)
Weight 4.1 kg (9 lb)