HP 8557A Spectrum Analyzer.
Performance Plus Economy 8557A is a 10kHz to 350 MHz spectrum analyzer plug-in for use with the 853A or 180-series display. The high performance and convenient operation of this economical unit is ideally suited for a variety of applications in production, R&D or field service measurements. Simple 3-Knob Operation Preset the 8557A to the color-coded, "basic-operation" settings, and use the coupled controls to make most measurements in three easy steps. Tune to the signal; the LED readout displays its frequency. Zoom-in on the signal by reducing the span width; the resolution bandwidth, video filter, and sweeptime automatically change to an optimum value for a calibrated display. Then, change the reference level to bring the peak of the signal to the top of the screen for the most accurate amplitude measurement. Absolute Amplitude Calibration Signal levels can be read directly from the CRT in dBm (dBmV for Option 002) without the use of external standards or calculations. The signal level represented by the top CRT graticule line is always indicated by the reference level control, and vertical scale factors of 10 dB/div, 1 dB/div or linear can be selected. Optional 75 Input Two options are available which allow measurements in 75 systems. Option 001 has 75 impedance, but retains the dBm power calibration. Option 002 is also 75 , but the amplitude is calibrated in dBmV for measurements on systems such as CATV