From hweber@uu.net Wed Feb 16 08:26:25 1994 Path: ashpoly!cascade!bigsur!uu!hweber From: hweber@uu.net (Heather Weber) Newsgroups: comp.dsp Subject: [INFO] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Feb16.082625.5093@uu.net> Date: Wed, 16 Feb 1994 08:26:25 GMT Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Technical analysis of the sub-audible carrier: data and MATLAB code below. A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. I've uploaded the C source for my decimation and bandpass filter to ftp.ashford-poly.edu. -- Heather Weber *PLONK* filter active for trolls. Decstation 5000/200 - NetBSD 1.0 From tlee@clari.net Wed Feb 16 15:26:25 1994 Path: ashpoly!bigsur!pacrim!jpgate!kamome!clari!tlee From: tlee@clari.net (Tobias Lee) Newsgroups: comp.dsp Subject: Re: [INFO] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Feb16.152625.5804@clari.net> Date: Wed, 16 Feb 1994 15:26:25 GMT References: <1994Feb16.082625.5093@uu.net> Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: TIN [version 1.2 PL2] Lines: 8 In article <1994Feb16.082625.5093@uu.net>, hweber@uu.net (Heather Weber) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. Prof. Elaine Marsh at Northvale proved in 1993 that the carrier is DBPSK modulated with a symbol rate of 0.71 Hz. -- Tobias Lee Tape trading list upon request. SASE required for international mail. From kandersson@purdue.edu Fri Feb 18 14:39:25 1994 Path: ashpoly!cascade!brgate!saturno!purdue!kandersson From: kandersson@purdue.edu (Katrin Andersson) Newsgroups: comp.dsp Subject: Re: [INFO] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Feb18.143925.7667@purdue.edu> Date: Fri, 18 Feb 1994 14:39:25 GMT References: <1994Feb16.082625.5093@uu.net> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1994Feb16.082625.5093@uu.net>, hweber@uu.net (Heather Weber) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. You're overlooking tape wow and flutter. A Revox B77 has at least 0.05% speed drift, which would smear a 14 Hz line across several bins. -- Katrin Andersson -- Purdue University Engineering Computer Network "Hold for relay." From mokonkwo@utexas.edu Sun Feb 20 11:33:25 1994 Path: ashpoly!cascade!mxgate!coyoacan!utexas!mokonkwo From: mokonkwo@utexas.edu (Mathieu Okonkwo) Newsgroups: comp.dsp Subject: Re: [INFO] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Feb20.113325.1183@utexas.edu> Date: Sun, 20 Feb 1994 11:33:25 GMT References: <1994Feb16.082625.5093@uu.net> <1994Feb16.152625.5804@clari.net> Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1994Feb16.152625.5804@clari.net>, tlee@clari.net (Tobias Lee) writes: > Prof. Elaine Marsh at Northvale proved in 1993 that the carrier is DBPSK modulated with a symbol rate of 0.71 Hz. That's how the 14 lines of the Stardust matrix are encoded. Each regional pressing contains one line of the decoded text. -- Mathieu Okonkwo Opinions expressed are solely my own and not those of University of Texas at Austin. ------------------------------------------------------------