The document compares the specifications of two pulse generators: the SRS DG 535 and the QC 9520. It shows that the QC 9520 has more features and flexibility across most categories, including communications interfaces, trigger/gate options, delay ranges and resolutions, internal rate generator performance, and I/O options. The QC 9520 also has modular options that allow for additional capabilities like incremental output, high voltage pulses, and dual optical/trigger inputs that are not available on the SRS DG 535. In summary, the QC 9520 generally outperforms the SRS DG 535 according to the specifications comparison chart.

1. QC vs. SRS - COMPARISON CHART
SPECIFICATIONS SRS DG 535 QC 9520 BETTER?
STANDARD FEATURES
Communications GPIB USB/RS232 (Optional Ethernet/GPIB) Yes!
Global Gates/Triggers 1 Global only 2 Global Gate/Trigger Inputs Yes!
Channel Gates/Triggers None Optical or Electrial (ea. channel gate only) Yes!
External Clock In/Out 10 MHz set 10 MHz - 100 MHz (discrete values) Yes!
Command Set Compatibility None Backwards Compatible Yes!
Modular Design None Yes Yes!
DELAYS
Range 0 - 1000 s 0 - 1000 s
Resolution 5 ps 250 ps
Accuracy 1500 ps + timebase error x delay 1000 ps + timebase error x delay Yes!
Timebase 25 ppm 1 ppm optional 25 ppm 1 ppm optional
RMS Jitter 50 ps + 10e-8 x delay 400 ps
Trigger Delay 85 ns 160 ns
Pulse Inhibit Delay Unknown < 120 ns
Output Inhibit Delay Unknown < 50 ns
INTERNAL RATE GENERATOR
Rate 0.001 Hz to 1.000 MHz 0.0002 Hz to 20.000 MHz Yes!
Resolution 4 digits, 0.001 Hz below 10 Hz 10 ns Yes!
Accuracy Same as timebase Same as timebase
Jitter 1:10,000 50 ps
Settling < 2 seconds for any rate change 1 cycle Yes!
Burst Mode 2 - 32766 1 to 9,999,999 Yes!
GATE INPUT(S)
Number 1 0 or 1
Threshold TTL 0.2 to 15 VDC Yes!
Max Input Voltage 60 V Peak Yes!
Resolution 10 mV
Polarity Active High Active High/Active Low Yes!
Function Externally Triggered Pulse Inhibit Pulse Inhibit or Output Inhibit Yes!
Channel Behavior Global Global or Individual Channel Enables Yes!
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2. QC vs. SRS - COMPARISON CHART
SPECIFICATIONS SRS DG 535 QC 9520 BETTER?
TTL/ADJUSTABLE OUTPUTS
Number 2 (4 edge outputs) 2, 4 or 8 (independent width & delay) Yes!
Load 50 ohm or high impedance 50 ohm or high impedance (no selection needed)
Rise time 3 ns typ. 3 ns typ.
Slew rate 1 V/ns 0.5 V/ns
Overshoot < 100 mV +10% pulse amp < 100 mV +10% pulse amp
Levels TTL 0 to 4 VDC TTL 0 to 4 VDC 4 VDC w/ TZ50
Adj -3 to +4 VDC with 10 mV resolution Adj 2.0 to 20.0 VDC (10 mV resolution) Yes!
4 VDC max transition 20 VDC max transition Yes!
TTL/ADJUSTABLE INPUTS
Number n/a 1 or 2 Yes!
Threshold n/a 0.2 to 15 VDC Yes!
Max Input Voltage n/a 60 V Peak Yes!
Resolution n/a 10 mV Yes!
Impedance n/a 1.5 K ohm + 40 pF Yes!
Function(s) n/a Individual channel pulse/output inhibit Yes!
Trigger Slope n/a Rising or Falling Yes!
OPTICAL OUTPUTS
Number n/a 2, 4 or 8 Yes!
Wavelength n/a 820 nm or 1300 nm Yes!
OPTICAL INPUTS
Number n/a 0 or 2 Yes!
Wavelength n/a 820 nm or 1300 nm Yes!
OPTIONS
Not Offered I - Incrementing Yes!
Not Offered High Voltage (35-45 V) Yes!
Not Offered COM - (Ethernet & GPIB) Yes!
Not Offered Dual Optical Output Module Yes!
Not Offered Dual Optical Input Module Yes!
Not Offered Dual Trigger Input Module Yes!
Toll Free (800) 510-6530 Email info@quantumcomposers.com
Fax (406) 582-0237 Web www.QuantumComposers.com V1.0 1/4/12