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  • Precise Differential or Single-Ended TDR – Time Domain Reflectometry in one convenient package
  • Compatible with the Picotest P2104A 1-port and P2105A TDR Browser Probes, as well as other manufacturers’ 50 Ohms probes
  • All applications requiring a fast, precise edge
  • Low cost; USB or battery powered


  • Low-cost PCB coupon tester - Characteristic Impedance PCB traces
  • Measure cable and PCB trace length, characteristic impedance, and dielectric constant
  • Locate and detect impedance mismatches
  • Measure parasitic values of inductance and capacitance such as bond wires, vias, and ESL
  • Verify the integrity of cable crimps and connector launches
  • Measure PCB trace path rise/fall time and overshoot/undershoot
  • Supports cable and trace loss modeling
  • Troubleshoot clock jitter and crosstalk
  • Measure microwave filters
  • Test the frequency bandwidth, rise/fall time, and flatness of lab instruments and probes


What's included:

  • J2154A PerfectPulse® Differential TDR
  • Picotest TDR Demo Trace Board
  • USB-C Cable
  • Two (2) BNC-SMA 12" PDN Cables®
  • 1 Year Warranty




The J2154A is a low-cost single or differential TDR in a portable package. It turns your oscilloscope into a PCB Trace, Cable, Connector, and Coupon Tester. With its 10.5GHz pulse generator and internal power splitter, the J2154A can make TDR, FRA (probe measurement), and VNA (S21) measurements. The J2154A has improved jitter (~20dB). The J2154A now comes in multiple colors. Please choose your color: silver, black, red, blue, or gold, when ordering.

The PerfectPulse signal generator provides a square ~30ps edge pulse in a pocket size, self-contained package, requiring only a USB power source. The affordable, small, simple to use, portable and lightweight unit with unique specifications for differential lines and high accuracy in detecting and locating small resolution impedance changes. The 50 Ohm output signal is very square, without overshoot or undershoot making it perfect for verifying instrument and probe rise/fall times, as well as verifying signal path rise/fall time and undershoot/overshoot. The addition of a 10GHz power splitter allows the signal generator to be used as a reflectometer for measuring PCB coupons, cable and PCB trace impedance, verifying cable crimps, measuring trace and cable lengths, dielectric constant and many other applications.

Modes of Operation and Connectivity
TDR – For single-ended and differential mode TDR measurements, Connectors 1 and 3 connect to the oscilloscope channels, while connectors 2 and 4 connect to the probes. This is the native mode and most common mode of operation. These can be either single-ended or differential measurements. Connectors 1 and 2 are used for single-ended measurements.


The Picotest TDR Demo board includes differential and single-ended test traces with varying impedances.

  • Trace 1 (TP1/TP2) – Single ended 50 Ohm trace
  • Trace 2 (TP3/TP4) – Single ended OhmBeatty standard
  • Trace 3 (TP5/TP6) – Single ended trace with two impedance steps 3000 mils apart
  • Trace 4 (TP7/TP9) – Differential 50 Ohm test traces
  • Trace 5 (TP11/TP12 and TP15/16) – Differential test traces; one with two impedance steps 200 mils apart and one with two larger discontinuities 750 mils apart
  • Trace 6 (TP13/TP14 and TP17/18) – Differential test traces; one with two impedance steps 500 mils apart and one with two larger impedance steps 1000 mils apart

Picotest J2154A PerfectPulse® Differential TDR

    • Works with any oscilloscope (50 ohms) that supports the math expressions
    • Typical rise/fall time: 30ps
    • Output Voltage 0 - 250mV +/-3mV @ 25C
    • Flatness 3dB at 10.5GHz 0.1dB (typ.) at 2GHz
    • Skew output to output: 2 psec
    • Return Loss: typical 55dB max 40dB
    • Resolutions ~164 mils (FR4) *
    • Connectors: SMA
    • 1MHz repetition rate – maximum cable length exceeds 50m
    • DC Input Power: USB Type C 5V 118mA typical 130mA max
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