Tektronix DA 4084 - Programmable Distortion Analyzer

The Tektronix DA4084 Programmable Distortion Analyzer is equivalent to the AA5001, a complete Distortion Analyzer System that's fully automatic. The major difference is that the DA4084 has SINAD function instead of Intermodulation (IMD). Once the mode is selected, automatic set level, automatic tuning, automatic nulling of the fundamental, and autoranging of the display all combine to permit completely hands-off operation!

Measurements are displayed on a 3 1/2-digit, 2000 count LED display and an analog-like bar graph that simulates an analog meter. Designed to meet rugged military specifications, the DA4084 comes with its own dedicated power source (modified TM5003) and delivers much more than just quality distortion measurements. It also has the ability to make automatic Level (volts or dBm), and dB Ratio measurements, plus four built-in frequency-weighting filters that can be switched into the signal path for preconditioning of the signal to be measured.

Programmable via the IEEE-488 interface allows this instrument to also be incorporated into ATE Systems for elaborate testing applications. Frequency: 10Hz to 100kHz; Input ranges: 200 µV to 200 V (10 steps). Distortion ranges: Auto (100%, 20%, 2%, 0.2%, and dB (autoranging); Accuracy: ±1 dB (20Hz to 20kHz); +1, -2 dB (10Hz to 100kHz).

• Fully Automatic: No Level Setting, Tuning, or Nulling
• Level, Total Harmonic Distortion, and dB Ratio Measurements
• Total System Harmonic Distortion Plus Noise (THD+N) < 0.0025% (with companion SG505/SG5010)
• <= 3.0 uV Residual Noise
• Digital Readout Plus Analog-Like "Bar Graph" for Peaking and Nulling
• Special Military Version of the AA5001 with SINAD measurement and dedicated mainframe

The DA4084 provides fully automated measurement of level and total harmonic distortion plus noise (THD+N). Automatic measurement means that once the mode is selected and the test signal is applied, the operator simply reads the accurate result on a 3-digit display. Functions such as level setting, tuning, and nulling are fully automatic.

The DA4084 provides dB-ratio measurements referenced either to 774.6 mV (1mW in 600 ohms) or to a user applied signal. The 0 dB reference memory stores selected level, and all subsequent measurements are referenced to it. The user can choose either rue-rms or average response. While true-rms is generally more accurate, the averaging feature is convenient for comparison of new data with data taken on older instruments where averaging was the only mode available.

The fundamental frequency range is 10 Hz to 100 kHz with harmonic measurements to 300 kHz. Any one of four built in frequency-weighting filters can be switched into the signal paths for input signal preconditioning. External filters can be simply connected for for special applications such as stereo pilot tone rejection, rejection of continuous tone squelch signals in mobile radio systems, or for selection of individual harmonics instead of total harmonic distortion measurements.

An input monitor connector and Function Output connector permit oscilloscope display of the input signal or the filtered signal input used in THD+N measurement.

• Fully automatic - no level setting, tuning, or nulling needed. 
• Fully automatic level (volts or dBm) and dB ratio measurements.
• 3 1/2 digit, 2000 count LED and analog bar graph displays.
• Frequency range: 10Hz to 100kHz.
• Input ranges: 200uV to 200V (10 steps).
• Distortion ranges: Auto (100%, 20%, 2%, 0.2%, and dB autoranging).
• GPIB.
• Includes power module.
• Four built-in frequency weighting filters that can be switched into signal path for signal preconditioning - any mode.