The Tektronix SD26 is a dual-channel, 20 GHz equivalent bandwidth sampling head designed for high-performance signal acquisition in Tektronix 11800 Series and CSA803 Series mainframes. It offers the same acquisition performance as the SD24 but without the TDR step generators, making it ideal for high-speed electrical sampling and measurement applications.

Specifications

General

ParameterValue
InterfacesProprietary internal mainframe interface connector
DisplayNone (utilizes mainframe display)

Physical

ParameterValue
Power SupplyPowered directly from mainframe
Operating Temperature0 °C to +50 °C
Dimensions (W×H×D)25.4 mm × 73.6 mm × 91.4 mm
Weight0.155 kg

Vertical System

ParameterValue
Number of Channels2
Equivalent Bandwidth20 GHz (typical)
Rise Time17.5 ps
Maximum Sample Repetition Rate200 kHz
Displayed Noise (Unity Dot Response, Maximum)1.2 mV
Displayed Noise (Unity Dot Response, Typical)750 µV
Displayed Noise (With Smoothing, Maximum)550 µV
Displayed Noise (With Smoothing, Typical)350 µV
Dot Transient Response Accuracy±5% for signals up to 0.5 Vp-p (after calibration at operating temperature)
Dot Transient Response RangeAdjustable to unity for signals up to 1.0 Vp-p
Aberrations (10 ns to 20 ps before step)±3% or less (typical)
Aberrations (<300 ps after step)+10%, -5% or less (typical)
Aberrations (300 ps to 5 ns after step)±3% or less (typical)
Aberrations (5 ns to 100 ns)±1% or less (typical)
Aberrations (elsewhere)±0.5% or less (typical)

Input Characteristics

ParameterValue
Input Impedance50 Ohm ±0.5 Ohm
Maximum Safe Input Voltage±3 V
Input Connector Type3.5 mm Female (SMA compatible)

Mainframe Compatibility

ParameterValue
Supported MainframesTektronix 11801, 11802, CSA803 series

Environmental

ParameterValue
Storage Temperature-40 °C to +75 °C
Operating Altitude4,570 m (15,000 ft)
Non-Operating Altitude15,240 m (50,000 ft)

Performance

ParameterValue
Channel-to-Channel Isolation≥ 34 dB at 20 GHz
Nominal Delay1.9 ns
Loop-Through Reflection Coefficient (within 150 ps of step)≤5%
Loop-Through Reflection Coefficient (elsewhere)≤2%
Loop-Through Insertion Loss (DC to 10 GHz)≤1.0 dB
Loop-Through Insertion Loss (10 GHz to 20 GHz)≤2.0 dB
Offset Range±1.0 V

Technology

Equivalent-Time Electrical Sampling

Applications

High-Speed Electrical Signal Analysis