Rise Time Converters For Simpler Tdr Testing Of Bandlimited Systems

Rise time converter is placed between STEP OUTPUT and SIGNAL IN connectors of -hp- TDR system, which consists of Model 1415A TDR Plug-in for Model 140A Oscilloscope. Fig. 2. Rise time converter is placed between STEP OUTPUT and SIGNAL IN connectors of -hp- TDR system, which consists of Model 1415A TDR Plug-in for Model 140A Oscilloscope. Time domain reflectometry (TDR) is a simple and accurate way to locate and analyze discontinuities in coaxial cables and microwave transmission...

Rise Time Converters

With a new series of Rise Time Converters (Fig. 1), the fast rise time of the normal TDR voltage step can be slowed to any of five values between 0.5 nanoseconds and 10 nanoseconds. The converters are low-pass filters which have been designed for minimum departure of the output step from a Gaussian leading edge and for minimum deviation from a 50-ohrn output impedance. The Gaussian leading edge makes the TDR test signal a good compromise in shape and frequency components for the range of...

Wide Range Scope

Apart from its stable dc operation, the new oscilloscope (-hp- Model 155A) is capable of high performance in many other respects. It is basically a general purpose, wideband, singlechannel oscilloscope with a high-frequency 3-dB point at 25 MHz (Y axis), a response figure that is referred to an 8-cm display rather than the 6-cm reference usually used for scopes with band-widths higher than 10 MHz. Rise time is less than 15 nanoseconds for 8-cm deflection and less than 20 nanoseconds with pulses...

New Tdr Application Note

A new application note, 'Selected Articles on Time Domain Reflectom-etry Applications has just been published. This note contains reprints of five articles on uses of TDR which originally appeared as technical reports, papers, and magazine articles. Titles of the articles are 1. Time Domain Reflectometry Theory and Applications 2. Transmission Line Pulse Reflectometry 3. Mechanical Scaling Enhances Time Domain Reflectometry Use The converters are inserted between the step output and signal in...

Time Domain Reflectometry In Ohm Systems

The -hp- TDR system1 has a characteristic impedance of 50 ohms because this is the most common impedance for cables and microwave systems. There are, however, other common impedances, and in the communication industries, in television broadcasting, and in community-antenna television systems, 75 ohms is widely used. Calibration and interpretation of the TDR display are simplest when the characteristic impedance of the TDR system is the same as the characteristic impedance of the system being...

Norman Overacker

Chuck House joined -hp- in 1962 after earning his BSEE degree from the California Institute of Technology. Two years later he earned his MSEE degree from Stanford University in the -hp- Honors Cooperative Program. At -hp-, Chuck initially worked as a development engineer on the 140A Oscilloscope and then on the design of the vertical amplifer in the Model 155A Oscilloscope. Norm Overacker started with -hp- in 1957 on a part-time basis while participating in a cooperative work-study program at...

Calibrated Susceptance For Tdr Measurements Of Small Reactive Discontinuities

Time domain reflectometry TDR , which is described briefly in another article in this issue, uses a pulse-echo technique to locate and characterize impedance discontinuities in cables and microwave devices. TDR offers many advantages over single-frequency or swept-frequency techniques, including its ability to locate reflections accurately and its ability to make accurate measurements of characteristic impedance Z0 provided that a known reference is available for comparison . One important...

R If

ANDERSON Dick Anderson joined -hp- in 1959 as a development engineer in the -hp-Microwave Division. His first project was the 851A 8551A Spectrum Analyzer and accessories. Since then, he has worked on a variety of microwave devices ranging from solid-state oscillators to wide-band high-precision directional couplers. He was project engineer for development of the 874A Calibrated Susceptance. His present position is engineering section manager, -hp- Microwave Laboratory. Dick received...