From jsouza@unam.mx Tue Mar 19 15:07:40 1996
Path: ashpoly!cascade!transat!sunet!nordrelay!unam!jsouza
From: jsouza@unam.mx (Joachim Souza)
Newsgroups: comp.dsp
Subject: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1996Mar19.150740.2768@unam.mx>
Date: Tue, 19 Mar 1996 15:07:40 GMT
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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.
With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs).

Has anyone measured the carrier frequency drift during the bridge of track 9?

-- 
Joachim Souza
Opinions expressed are solely my own and not those of Universidad Nacional Autónoma de México (DGSCA).
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From jweber@titech.ac.jp Wed Mar 20 12:25:40 1996
Path: ashpoly!cascade!brgate!saturno!titech!jweber
From: jweber@titech.ac.jp (Joachim Weber)
Newsgroups: comp.dsp
Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1996Mar20.122540.5047@titech.ac.jp>
Date: Wed, 20 Mar 1996 12:25:40 GMT
References: <1996Mar19.150740.2768@unam.mx>
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In article <1996Mar19.150740.2768@unam.mx>, jsouza@unam.mx (Joachim Souza) writes:
> Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line.

Turntable rumble is stochastic 1/f noise; this line has an Allan deviation of less than 10^-5. It was generated by a quartz crystal clock.

-- 
Joachim Weber
Tape trading list upon request. SASE required for international mail.

From aandersson@berkeley.edu Wed Mar 20 16:28:40 1996
Path: ashpoly!cascade!transat!ukc!fennimore!berkeley!aandersson
From: aandersson@berkeley.edu (Aiko Andersson)
Newsgroups: comp.dsp
Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1996Mar20.162840.7993@berkeley.edu>
Date: Wed, 20 Mar 1996 16:28:40 GMT
References: <1996Mar19.150740.2768@unam.mx>
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In article <1996Mar19.150740.2768@unam.mx>, jsouza@unam.mx (Joachim Souza) 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.

Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature.

-- 
Aiko Andersson | aandersson@berkeley.edu
PGP Key fingerprint: EAC1 01F5 82FB 069A
"Keep the channels open."

From jpopov@cam.ac.uk Thu Mar 21 07:42:40 1996
Path: ashpoly!cascade!mxgate!coyoacan!cam!jpopov
From: jpopov@cam.ac.uk (Joachim Popov)
Newsgroups: comp.dsp
Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1996Mar21.074240.2457@cam.ac.uk>
Date: Thu, 21 Mar 1996 07:42:40 GMT
References: <1996Mar19.150740.2768@unam.mx> <1996Mar20.122540.5047@titech.ac.jp>
Organization: University of Cambridge Computer Laboratory
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In article <1996Mar20.122540.5047@titech.ac.jp>, jweber@titech.ac.jp (Joachim Weber) writes:
> Turntable rumble is stochastic 1/f noise; this line has an Allan deviation of less than 10^-5. It was generated by a quartz crystal clock.

If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386.

Top-posters will be placed in my ~/.killfile without notice.

-- 
Joachim Popov
Opinions expressed are solely my own and not those of University of Cambridge Computer Laboratory.
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