MEITNER LIM DETECTOR

Design Features

Logic Induced Modulation (LIM™) is a phenomenon that seriously degrades the performance of digital audio circuits. It is well explained in a paper entitled: "Time Distortions Within Digital Audio Equipment Due to Integrated Circuit Logic Induced Modulation Products" by Ed Meitner and Rob Gendron. This paper is in the AES archives.

The LIM Detector is unique as a jitter analysis tool. It works intuitively with you to help resolve the spectral components of jitter. The output of the LIM Detector is a 20KHz band limited audio signal. This signal can drive a Spectrum Analyzer to display the audio-band jitter spectrum.

A short discussion of Phase, Frequency and Rotating Vectors by ADST Engineer, Campbell Kelly, contains supplemental information pertaining to LIM.

Specifications

Phase Demodulated

Frequency response (-3dB) 20 Hz - - 20 KHz
Calibration: 10nS p-p = 100 mV RMS (1 KHz)

Phase Modulated

(8Fs, 1KHz modulation) Resolution better than 10 pS (100uV) Maximum 500nS (5V)

General

VCXO Tracking Range: +/- 600 ppm
Input Coupling: AC or DC
Input Slope: Switch Selected.
Input Sensitivity: 50 mV -- 5V p-p
Audio Output Impedance: 50 Ohms.
Power Supply: Internal Meitner floating charge design.
Power Requirements: 117V or 220V - 50 or 60 Hz.
Dimensions: 3.75" X 8.25" X 12.0".

High frequency selected at Fs relative to 32, 44.1 and 48 Khz. Sixteen steps allow 2 Fs to 768 Fs supporting the most common digital audio sample rates.