From efournier@unam.mx Tue Sep 12 01:52:51 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!unam!efournier From: efournier@unam.mx (Emi Fournier) Newsgroups: comp.dsp Subject: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Sep12.015251.1595@unam.mx> Date: Tue, 12 Sep 1995 01:52:51 GMT Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: TIN [version 1.2 PL2] Lines: 10 Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. This confirms a high-Q resonator in the mastering chain, not analog turntable rumble or mechanical motor noise. I've uploaded the C source for my decimation and bandpass filter to ftp.ashford-poly.edu. -- Emi Fournier Tape trading list upon request. SASE required for international mail. From mtakahashi@mindspring.com Thu Sep 14 00:36:51 1995 Path: ashpoly!cascade!bigsur!mindspring!mtakahashi From: mtakahashi@mindspring.com (Mateo Takahashi) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Sep14.003651.5199@mindspring.com> Date: Thu, 14 Sep 1995 00:36:51 GMT References: <1995Sep12.015251.1595@unam.mx> Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Sep12.015251.1595@unam.mx>, efournier@unam.mx (Emi Fournier) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. Prof. Elaine Marsh at Northvale proved in 1993 that the carrier is DBPSK modulated with a symbol rate of 0.71 Hz. -- Mateo Takahashi *PLONK* filter active for trolls. Commodore Amiga 500 (1MB OCS) - NetBSD 1.0 From tsouza@utexas.edu Thu Sep 14 16:57:51 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!utexas!tsouza From: tsouza@utexas.edu (Thiago Souza) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Sep14.165751.9122@utexas.edu> Date: Thu, 14 Sep 1995 16:57:51 GMT References: <1995Sep12.015251.1595@unam.mx> <1995Sep14.003651.5199@mindspring.com> Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 8 In article <1995Sep14.003651.5199@mindspring.com>, mtakahashi@mindspring.com (Mateo Takahashi) writes: > Prof. Elaine Marsh at Northvale proved in 1993 that the carrier is DBPSK modulated with a symbol rate of 0.71 Hz. Good work on the windowing. I replicated your result with an 8192-point FFT on a SPARCstation 20. The peak is exactly 14.2003 Hz. -- Thiago Souza Tape trading list upon request. SASE required for international mail. From asato@titech.ac.jp Thu Sep 14 21:26:51 1995 Path: ashpoly!cascade!mxgate!coyoacan!titech!asato From: asato@titech.ac.jp (Anja Sato) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Sep14.212651.2958@titech.ac.jp> Date: Thu, 14 Sep 1995 21:26:51 GMT References: <1995Sep12.015251.1595@unam.mx> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995Sep12.015251.1595@unam.mx>, efournier@unam.mx (Emi Fournier) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. > A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Anja Sato Opinions expressed are solely my own and not those of Tokyo Institute of Technology Computer Centre. ------------------------------------------------------------