Supporting Calibration Labs Since 2008

Model 1240 Ultra-High Speed Reference Pulse Generator -
Two Outputs: 9 ps & 18 ps Transition Duration

The Model 1240 Ultra-High Speed Reference Pulse Generator was designed to provide pulses suitable to calibrate oscilloscopes with up to 50 GHz bandwidth. A second output provides pulses for calibrating oscilloscopes with up to 18 GHz bandwidth. It provides both a short positive and short negative-going transition duration (typical risetimes are 10 ps and 24 ps and typical falltimes are 9 ps and 18 ps). It exhibits a low short term settling error of less than 1 % in 10 nanoseconds. The output levels are approximately -600 mV and 0 V and the resulting 600 mV pulse amplitude exercises the inputs of sampling oscilloscopes by supplying a pulse that is up to 75 % of oscilloscope's input operating range. Both the transition durations and amplitudes are calibrated. (Option 1: output levels of 0 V and +600 mV.)

The pulse head is attached to the mainframe by a 3 foot long cable pair that allows the pulse head output to be connected directly to the oscilloscope input without any intervening cables that can slow the pulse transition. The higher speed output connector is a male 2.4 mm coaxial connector designed to mate with most ultra-high speed oscilloscope inputs without an adapter. The lower speed output connector is a male 3.5 mm coaxial connector(Option 3: user specified output connector - 1.85 mm, 2.4 mm male or female and 2.92 mm, SMA male or female.)

Typical Performance of High Speed Output

• 9 ps negative-going transition duration (10 % to 90 % falltime)
• 10 ps positive-going transition duration (10 % to 90 % risetime)
• 600 mV amplitude
• 50 GHz (-3dB) bandwidth (from FFT of measured waveform)
• 15 % overshoot (positive and negative-going transition)
• 10 % undershoot (positive-going transition), 4 % (negative-going transition)
• 1 % short term settling error in 10 ns epoch
• 5 % settling error in 100 ns epoch
• 80 MHz to 12 GHz pulse repetition rate
• ± 0.4 ps rms jitter

Typical Performance of Low Speed Output

• 18 ps negative-going transition duration (10 % to 90 % falltime)
• 24 ps positive-going transition duration (10 % to 90 % risetime)
• 550 mV amplitude
• 18 GHz (-3dB) bandwidth (from FFT of measured waveform)
• 15 % overshoot (positive and negative-going transition)
• 10 % undershoot (positive-going transition), 4 % (negative-going transition)
• 1 % short term settling error in 10 ns epoch
• 5 % settling error in 100 ns epoch
• 80 MHz to 6 GHz pulse repetition rate
• ± 0.4 ps rms jitter

Pulse Head Dimensions

• Height: 66.4 mm (2.615 in.)
• Width: 39.6 mm (1.56 in.)
• Depth: 69.8 mm (2.75 in.)

Options

• Option 1: the output switches between 0 V and +600 mV
• Option 2: change oscillator frequency
• Option 3: change pulse output connector - N, SMA, 2.92 mm, 3.5 mm, 2.4 mm, 1.85 mm
• Option 4: 220 VAC, 50 Hz power input for use in Europe and other locations